Android Studio Bumble Bee Essentials - Java Edition

Description

Fully updated for Android Studio Bumble Bee, the goal of this book is to teach the skills necessary to develop Android-based applications using the Java programming language. Beginning with the basics, this book provides an outline of the steps necessary to set up an Android development and testing environment. An overview of Android Studio is included covering areas such as tool windows, the code editor, and the Layout Editor tool. An introduction to the architecture of Android is followed by an in-depth look at the design of Android applications and user interfaces using the Android Studio environment. Chapters are also included covering the Android Architecture Components including view models, lifecycle management, Room database access, the Database Inspector, app navigation, live data, and data binding. More advanced topics such as intents are also covered, as are touch screen handling, gesture recognition, and the recording and playback of audio. This edition of the book also covers printing, transitions, cloud-based file storage, and foldable device support. The concepts of material design are also covered in detail, including the use of floating action buttons, Snackbars, tabbed interfaces, card views, navigation drawers, and collapsing toolbars. Other key features of Android Studio Bumble Bee and Android are also covered in detail including the Layout Editor, the ConstraintLayout and ConstraintSet classes, MotionLayout Editor, view binding, constraint chains, barriers, and direct reply notifications. Chapters also cover advanced features of Android Studio such as App Links, Dynamic Delivery, Gradle build configuration, and submitting apps to the Google Play Developer Console. Assuming you already have some Java programming experience, are ready to download Android Studio and the Android SDK, have access to a Windows, Mac, or Linux system, and have ideas for some apps to develop, you are ready to get started. Table of Contents 1. Introduction ............................................................................................................................................... 1 1.1 Downloading the Code Samples....................................................................................................... 1 1.2 Feedback............................................................................................................................................... 1 1.3 Errata..................................................................................................................................................... 2 2. Setting up an Android Studio Development Environment....................................................................... 3 2.1 System Requirements.......................................................................................................................... 3 2.2 Downloading the Android Studio Package ..................................................................................... 3 2.3 Installing Android Studio................................................................................................................... 4 2.3.1 Installation on Windows............................................................................................................. 4 2.3.2 Installation on macOS ................................................................................................................. 4 2.3.3 Installation on Linux.................................................................................................................... 5 2.4 The Android Studio Setup Wizard.................................................................................................... 5 2.5 Installing Additional Android SDK Packages................................................................................. 6 2.6 Making the Android SDK Tools Command-line Accessible......................................................... 9 2.6.1 Windows 8.1 ................................................................................................................................. 9 2.6.2 Windows 10 ................................................................................................................................ 10 2.6.3 Windows 11 ................................................................................................................................ 10 2.6.4 Linux ............................................................................................................................................ 10 2.6.5 macOS.......................................................................................................................................... 10 2.7 Android Studio Memory Management.......................................................................................... 11 2.8 Updating Android Studio and the SDK ......................................................................................... 12 2.9 Summary ............................................................................................................................................ 12 3. Creating an Example Android App in Android Studio........................................................................... 13 3.1 About the Project .............................................................................................................................. 13 3.2 Creating a New Android Project..................................................................................................... 13 3.3 Creating an Activity ......................................................................................................................... 14 3.4 Defining the Project and SDK Settings .......................................................................................... 14 3.5 Modifying the Example Application............................................................................................... 15 3.6 Modifying the User Interface .......................................................................................................... 16 3.7 Reviewing the Layout and Resource Files...................................................................................... 21 3.8 Adding Interaction............................................................................................................................ 24 3.9 Summary ............................................................................................................................................ 25 4. Creating an Android Virtual Device (AVD) in Android Studio............................................................. 27 4.1 About Android Virtual Devices ...................................................................................................... 27 4.2 Starting the Emulator........................................................................................................................ 28 4.3 Running the Application in the AVD............................................................................................. 29 4.4 Running on Multiple Devices.......................................................................................................... 31 4.5 Stopping a Running Application..................................................................................................... 31 4.6 Supporting Dark Theme................................................................................................................... 32 4.7 Running the Emulator in a Separate Window............................................................................... 33 4.8 Enabling the Device Frame.............................................................................................................. 34 ii Table of Contents 4.9 AVD Command-line Creation ........................................................................................................ 35 4.10 Android Virtual Device Configuration Files............................................................................... 37 4.11 Moving and Renaming an Android Virtual Device ................................................................... 37 4.12 Summary .......................................................................................................................................... 37 5. Using and Configuring the Android Studio AVD Emulator .................................................................. 39 5.1 The Emulator Environment ............................................................................................................. 39 5.2 Emulator Toolbar Options............................................................................................................... 39 5.3 Working in Zoom Mode .................................................................................................................. 41 5.4 Resizing the Emulator Window....................................................................................................... 41 5.5 Extended Control Options............................................................................................................... 41 5.5.1 Location....................................................................................................................................... 42 5.5.2 Displays........................................................................................................................................ 42 5.5.3 Cellular ........................................................................................................................................ 42 5.5.4 Battery.......................................................................................................................................... 42 5.5.5 Camera......................................................................................................................................... 42 5.5.6 Phone ........................................................................................................................................... 42 5.5.7 Directional Pad........................................................................................................................... 42 5.5.8 Microphone................................................................................................................................. 42 5.5.9 Fingerprint .................................................................................................................................. 42 5.5.10 Virtual Sensors ......................................................................................................................... 43 5.5.11 Snapshots................................................................................................................................... 43 5.5.12 Record and Playback ............................................................................................................... 43 5.5.13 Google Play ............................................................................................................................... 43 5.5.14 Settings ...................................................................................................................................... 43 5.5.15 Help............................................................................................................................................ 43 5.6 Working with Snapshots................................................................................................................... 43 5.7 Configuring Fingerprint Emulation ............................................................................................... 44 5.8 The Emulator in Tool Window Mode............................................................................................. 45 5.9 Summary ............................................................................................................................................ 46 6. A Tour of the Android Studio User Interface .......................................................................................... 47 6.1 The Welcome Screen......................................................................................................................... 47 6.2 The Main Window ............................................................................................................................ 48 6.3 The Tool Windows............................................................................................................................ 49 6.4 Android Studio Keyboard Shortcuts .............................................................................................. 52 6.5 Switcher and Recent Files Navigation ............................................................................................ 53 6.6 Changing the Android Studio Theme ............................................................................................ 53 6.7 Summary ............................................................................................................................................ 54 7. Testing Android Studio Apps on a Physical Android Device.................................................................. 55 7.1 An Overview of the Android Debug Bridge (ADB)..................................................................... 55 7.2 Enabling USB Debugging ADB on Android Devices................................................................... 55 7.2.1 macOS ADB Configuration...................................................................................................... 56 7.2.2 Windows ADB Configuration.................................................................................................. 57 7.2.3 Linux adb Configuration........................................................................................................... 58 7.3 Resolving USB Connection Issues.................................................................................................. 58 7.4 Enabling Wireless Debugging on Android Devices..................................................................... 59 7.5 Testing the adb Connection............................................................................................................. 61 7.6 Summary ............................................................................................................................................ 61 iii Table of Contents 8. The Basics of the Android Studio Code Editor........................................................................................ 63 8.1 The Android Studio Editor............................................................................................................... 63 8.2 Splitting the Editor Window............................................................................................................ 65 8.3 Code Completion.............................................................................................................................. 66 8.4 Statement Completion...................................................................................................................... 67 8.5 Parameter Information..................................................................................................................... 68 8.6 Parameter Name Hints..................................................................................................................... 68 8.7 Code Generation............................................................................................................................... 68 8.8 Code Folding...................................................................................................................................... 69 8.9 Quick Documentation Lookup ....................................................................................................... 70 8.10 Code Reformatting.......................................................................................................................... 71 8.11 Finding Sample Code ..................................................................................................................... 71 8.12 Live Templates................................................................................................................................. 72 8.13 Summary .......................................................................................................................................... 72 9. An Overview of the Android Architecture .............................................................................................. 73 9.1 The Android Software Stack ............................................................................................................ 73 9.2 The Linux Kernel............................................................................................................................... 74 9.3 Android Runtime – ART.................................................................................................................. 74 9.4 Android Libraries.............................................................................................................................. 74 9.4.1 C/C++ Libraries ......................................................................................................................... 75 9.5 Application Framework.................................................................................................................... 75 9.6 Applications ....................................................................................................................................... 76 9.7 Summary ............................................................................................................................................ 76 10. The Anatomy of an Android Application .............................................................................................. 77 10.1 Android Activities........................................................................................................................... 77 10.2 Android Fragments......................................................................................................................... 77 10.3 Android Intents............................................................................................................................... 78 10.4 Broadcast Intents............................................................................................................................. 78 10.5 Broadcast Receivers ........................................................................................................................ 78 10.6 Android Services............................................................................................................................. 78 10.7 Content Providers........................................................................................................................... 79 10.8 The Application Manifest............................................................................................................... 79 10.9 Application Resources.................................................................................................................... 79 10.10 Application Context...................................................................................................................... 79 10.11 Summary ........................................................................................................................................ 79 11. An Overview of Android View Binding................................................................................................. 81 11.1 Find View by Id ............................................................................................................................... 81 11.2 View Binding .................................................................................................................................. 81 11.3 Converting the AndroidSample project....................................................................................... 82 11.4 Enabling View Binding................................................................................................................... 82 11.5 Using View Binding ........................................................................................................................ 82 11.6 Choosing an Option ....................................................................................................................... 83 11.7 View Binding in the Book Examples............................................................................................ 83 11.8 Migrating a Project to View Binding............................................................................................ 84 11.9 Summary .......................................................................................................................................... 85 12. Understanding Android Application and Activity Lifecycles............................................................... 87 12.1 Android Applications and Resource Management..................................................................... 87 iv Table of Contents 12.2 Android Process States................................................................................................................... 87 12.2.1 Foreground Process ................................................................................................................. 88 12.2.2 Visible Process.......................................................................................................................... 88 12.2.3 Service Process ......................................................................................................................... 88 12.2.4 Background Process................................................................................................................. 88 12.2.5 Empty Process .......................................................................................................................... 89 12.3 Inter-Process Dependencies ......................................................................................................... 89 12.4 The Activity Lifecycle...................................................................................................................... 89 12.5 The Activity Stack............................................................................................................................ 89 12.6 Activity States .................................................................................................................................. 90 12.7 Configuration Changes .................................................................................................................. 90 12.8 Handling State Change................................................................................................................... 91 12.9 Summary .......................................................................................................................................... 91 13. Handling Android Activity State Changes............................................................................................. 93 13.1 New vs. Old Lifecycle Techniques................................................................................................. 93 13.2 The Activity and Fragment Classes............................................................................................... 93 13.3 Dynamic State vs. Persistent State................................................................................................. 95 13.4 The Android Lifecycle Methods.................................................................................................... 96 13.5 Lifetimes........................................................................................................................................... 97 13.6 Foldable Devices and Multi-Resume............................................................................................ 98 13.7 Disabling Configuration Change Restarts................................................................................... 98 13.8 Lifecycle Method Limitations........................................................................................................ 98 13.9 Summary .......................................................................................................................................... 99 14. Android Activity State Changes by Example ....................................................................................... 101 14.1 Creating the State Change Example Project.............................................................................. 101 14.2 Designing the User Interface ....................................................................................................... 102 14.3 Overriding the Activity Lifecycle Methods ............................................................................... 102 14.4 Filtering the Logcat Panel.............................................................................................................104 14.5 Running the Application.............................................................................................................. 105 14.6 Experimenting with the Activity................................................................................................. 106 14.7 Summary ........................................................................................................................................ 107 15. Saving and Restoring the State of an Android Activity ....................................................................... 109 15.1 Saving Dynamic State ................................................................................................................... 109 15.2 Default Saving of User Interface State ........................................................................................ 109 15.3 The Bundle Class........................................................................................................................... 110 15.4 Saving the State.............................................................................................................................. 111 15.5 Restoring the State ........................................................................................................................ 112 15.6 Testing the Application................................................................................................................. 112 15.7 Summary ........................................................................................................................................ 112 16. Understanding Android Views, View Groups and Layouts ................................................................ 115 16.1 Designing for Different Android Devices.................................................................................. 115 16.2 Views and View Groups............................................................................................................... 115 16.3 Android Layout Managers........................................................................................................... 115 16.4 The View Hierarchy ...................................................................................................................... 117 16.5 Creating User Interfaces............................................................................................................... 118 16.6 Summary ........................................................................................................................................ 118 17. A Guide to the Android Studio Layout Editor Tool ............................................................................ 119 v Table of Contents 17.1 Basic vs. Empty Activity Templates ............................................................................................ 119 17.2 The Android Studio Layout Editor............................................................................................. 123 17.3 Design Mode.................................................................................................................................. 123 17.4 The Palette ...................................................................................................................................... 124 17.5 Design Mode and Layout Views..................................................................................................125 17.6 Night Mode .................................................................................................................................... 126 17.7 Code Mode..................................................................................................................................... 126 17.8 Split Mode ...................................................................................................................................... 127 17.9 Setting Attributes...........................................................................................................................127 17.10 Transforms................................................................................................................................... 129 17.11 Tools Visibility Toggles............................................................................................................... 130 17.12 Converting Views........................................................................................................................ 132 17.13 Displaying Sample Data ............................................................................................................. 132 17.14 Creating a Custom Device Definition..................................................................................... 133 17.15 Changing the Current Device....................................................................................................134 17.16 Layout Validation (Multi Preview)........................................................................................... 134 17.17 Summary ...................................................................................................................................... 135 18. A Guide to the Android ConstraintLayout.......................................................................................... 137 18.1 How ConstraintLayout Works..................................................................................................... 137 18.1.1 Constraints.............................................................................................................................. 137 18.1.2 Margins.................................................................................................................................... 138 18.1.3 Opposing Constraints............................................................................................................138 18.1.4 Constraint Bias....................................................................................................................... 139 18.1.5 Chains...................................................................................................................................... 140 18.1.6 Chain Styles............................................................................................................................. 140 18.2 Baseline Alignment....................................................................................................................... 141 18.3 Configuring Widget Dimensions................................................................................................ 141 18.4 Guideline Helper........................................................................................................................... 142 18.5 Group Helper................................................................................................................................. 142 18.6 Barrier Helper................................................................................................................................ 142 18.7 Flow Helper.................................................................................................................................... 144 18.8 Ratios.............................................................................................................................................. 145 18.9 ConstraintLayout Advantages..................................................................................................... 145 18.10 ConstraintLayout Availability....................................................................................................146 18.11 Summary ...................................................................................................................................... 146 19. A Guide to Using ConstraintLayout in Android Studio ..................................................................... 147 19.1 Design and Layout Views............................................................................................................. 147 19.2 Autoconnect Mode ....................................................................................................................... 148 19.3 Inference Mode.............................................................................................................................. 149 19.4 Manipulating Constraints Manually........................................................................................... 149 19.5 Adding Constraints in the Inspector.......................................................................................... 150 19.6 Viewing Constraints in the Attributes Window........................................................................ 151 19.7 Deleting Constraints..................................................................................................................... 152 19.8 Adjusting Constraint Bias............................................................................................................ 152 19.9 Understanding ConstraintLayout Margins................................................................................ 153 19.10 The Importance of Opposing Constraints and Bias............................................................... 154 19.11 Configuring Widget Dimensions.............................................................................................. 156 19.12 Design Time Tools Positioning ................................................................................................. 157 vi Table of Contents 19.13 Adding Guidelines...................................................................................................................... 158 19.14 Adding Barriers........................................................................................................................... 160 19.15 Adding a Group........................................................................................................................... 161 19.16 Working with the Flow Helper.................................................................................................. 162 19.17 Widget Group Alignment and Distribution............................................................................ 163 19.18 Converting other Layouts to ConstraintLayout...................................................................... 164 19.19 Summary ..................................................................................................................................... 164 20. Working with ConstraintLayout Chains and Ratios in Android Studio ............................................ 165 20.1 Creating a Chain............................................................................................................................165 20.2 Changing the Chain Style ............................................................................................................ 167 20.3 Spread Inside Chain Style.............................................................................................................167 20.4 Packed Chain Style........................................................................................................................ 168 20.5 Packed Chain Style with Bias....................................................................................................... 168 20.6 Weighted Chain............................................................................................................................. 168 20.7 Working with Ratios..................................................................................................................... 169 20.8 Summary ........................................................................................................................................ 171 21. An Android Studio Layout Editor ConstraintLayout Tutorial ........................................................... 173 21.1 An Android Studio Layout Editor Tool Example ..................................................................... 173 21.2 Creating a New Activity ............................................................................................................... 173 21.3 Preparing the Layout Editor Environment................................................................................ 175 21.4 Adding the Widgets to the User Interface.................................................................................. 176 21.5 Adding the Constraints................................................................................................................ 179 21.6 Testing the Layout......................................................................................................................... 180 21.7 Using the Layout Inspector.......................................................................................................... 181 21.8 Summary ........................................................................................................................................ 182 22. Manual XML Layout Design in Android Studio ................................................................................. 183 22.1 Manually Creating an XML Layout............................................................................................ 183 22.2 Manual XML vs. Visual Layout Design...................................................................................... 186 22.3 Summary ........................................................................................................................................ 186 23. Managing Constraints using Constraint Sets...................................................................................... 187 23.1 Java Code vs. XML Layout Files.................................................................................................. 187 23.2 Creating Views............................................................................................................................... 187 23.3 View Attributes.............................................................................................................................. 188 23.4 Constraint Sets............................................................................................................................... 188 23.4.1 Establishing Connections......................................................................................................188 23.4.2 Applying Constraints to a Layout ........................................................................................ 188 23.4.3 Parent Constraint Connections............................................................................................ 188 23.4.4 Sizing Constraints.................................................................................................................. 189 23.4.5 Constraint Bias....................................................................................................................... 189 23.4.6 Alignment Constraints.......................................................................................................... 189 23.4.7 Copying and Applying Constraint Sets............................................................................... 189 23.4.8 ConstraintLayout Chains...................................................................................................... 189 23.4.9 Guidelines ............................................................................................................................... 190 23.4.10 Removing Constraints......................................................................................................... 190 23.4.11 Scaling....................................................................................................................................190 23.4.12 Rotation................................................................................................................................. 191 23.5 Summary ........................................................................................................................................ 191 vii Table of Contents 24. An Android ConstraintSet Tutorial..................................................................................................... 193 24.1 Creating the Example Project in Android Studio..................................................................... 193 24.2 Adding Views to an Activity........................................................................................................ 193 24.3 Setting View Attributes................................................................................................................. 194 24.4 Creating View IDs......................................................................................................................... 195 24.5 Configuring the Constraint Set................................................................................................... 196 24.6 Adding the EditText View............................................................................................................ 197 24.7 Converting Density Independent Pixels (dp) to Pixels (px).................................................... 198 24.8 Summary ........................................................................................................................................ 199 25. A Guide to using Apply Changes in Android Studio........................................................................... 201 25.1 Introducing Apply Changes......................................................................................................... 201 25.2 Understanding Apply Changes Options.................................................................................... 201 25.3 Using Apply Changes.................................................................................................................... 202 25.4 Configuring Apply Changes Fallback Settings.......................................................................... 203 25.5 An Apply Changes Tutorial..........................................................................................................203 25.6 Using Apply Code Changes......................................................................................................... 203 25.7 Using Apply Changes and Restart Activity................................................................................ 204 25.8 Using Run App .............................................................................................................................. 204 25.9 Summary ........................................................................................................................................ 205 26. An Overview and Example of Android Event Handling ..................................................................... 207 26.1 Understanding Android Events...................................................................................................207 26.2 Using the android:onClick Resource.......................................................................................... 207 26.3 Event Listeners and Callback Methods...................................................................................... 208 26.4 An Event Handling Example ....................................................................................................... 208 26.5 Designing the User Interface ....................................................................................................... 209 26.6 The Event Listener and Callback Method.................................................................................. 210 26.7 Consuming Events........................................................................................................................ 211 26.8 Summary ........................................................................................................................................ 212 27. Android Touch and Multi-touch Event Handling ............................................................................... 213 27.1 Intercepting Touch Events ........................................................................................................... 213 27.2 The MotionEvent Object.............................................................................................................. 213 27.3 Understanding Touch Actions..................................................................................................... 214 27.4 Handling Multiple Touches ......................................................................................................... 214 27.5 An Example Multi-Touch Application....................................................................................... 214 27.6 Designing the Activity User Interface ........................................................................................ 215 27.7 Implementing the Touch Event Listener.................................................................................... 215 27.8 Running the Example Application............................................................................................. 218 27.9 Summary ........................................................................................................................................ 219 28. Detecting Common Gestures Using the Android Gesture Detector Class......................................... 221 28.1 Implementing Common Gesture Detection.............................................................................. 221 28.2 Creating an Example Gesture Detection Project ...................................................................... 222 28.3 Implementing the Listener Class................................................................................................. 222 28.4 Creating the GestureDetectorCompat Instance........................................................................ 224 28.5 Implementing the onTouchEvent() Method.............................................................................. 225 28.6 Testing the Application................................................................................................................. 225 28.7 Summary ........................................................................................................................................ 226 viii Table of Contents 29. Implementing Custom Gesture and Pinch Recognition on Android ................................................. 227 29.1 The Android Gesture Builder Application................................................................................. 227 29.2 The GestureOverlayView Class................................................................................................... 227 29.3 Detecting Gestures........................................................................................................................ 227 29.4 Identifying Specific Gestures....................................................................................................... 227 29.5 Installing and Running the Gesture Builder Application ........................................................ 228 29.6 Creating a Gestures File ............................................................................................................... 228 29.7 Creating the Example Project...................................................................................................... 228 29.8 Extracting the Gestures File from the SD Card ........................................................................ 229 29.9 Adding the Gestures File to the Project ..................................................................................... 229 29.10 Designing the User Interface ..................................................................................................... 229 29.11 Loading the Gestures File .......................................................................................................... 230 29.12 Registering the Event Listener................................................................................................... 231 29.13 Implementing the onGesturePerformed Method................................................................... 231 29.14 Testing the Application...............................................................................................................232 29.15 Configuring the GestureOverlayView...................................................................................... 233 29.16 Intercepting Gestures..................................................................................................................233 29.17 Detecting Pinch Gestures........................................................................................................... 233 29.18 A Pinch Gesture Example Project............................................................................................. 234 29.19 Summary ...................................................................................................................................... 236 30. An Introduction to Android Fragments.............................................................................................. 237 30.1 What is a Fragment?..................................................................................................................... 237 30.2 Creating a Fragment ..................................................................................................................... 237 30.3 Adding a Fragment to an Activity using the Layout XML File............................................... 238 30.4 Adding and Managing Fragments in Code ............................................................................... 240 30.5 Handling Fragment Events.......................................................................................................... 241 30.6 Implementing Fragment Communication................................................................................. 242 30.7 Summary ....................................................................................................................................... 243 31. Using Fragments in Android Studio - An Example............................................................................. 245 31.1 About the Example Fragment Application ................................................................................ 245 31.2 Creating the Example Project...................................................................................................... 245 31.3 Creating the First Fragment Layout............................................................................................ 245 31.4 Migrating a Fragment to View Binding ..................................................................................... 247 31.5 Adding the Second Fragment...................................................................................................... 248 31.6 Adding the Fragments to the Activity ........................................................................................ 249 31.7 Making the Toolbar Fragment Talk to the Activity .................................................................. 250 31.8 Making the Activity Talk to the Text Fragment ........................................................................ 253 31.9 Testing the Application................................................................................................................. 254 31.10 Summary ...................................................................................................................................... 255 32. Modern Android App Architecture with Jetpack ................................................................................ 257 32.1 What is Android Jetpack? ............................................................................................................ 257 32.2 The “Old” Architecture................................................................................................................. 257 32.3 Modern Android Architecture .................................................................................................... 257 32.4 The ViewModel Component ....................................................................................................... 258 32.5 The LiveData Component............................................................................................................ 258 32.6 ViewModel Saved State.................................................................................................................259 32.7 LiveData and Data Binding.......................................................................................................... 260 ix Table of Contents 32.8 Android Lifecycles ........................................................................................................................ 260 32.9 Repository Modules...................................................................................................................... 260 32.10 Summary ...................................................................................................................................... 261 33. An Android Jetpack ViewModel Tutorial............................................................................................ 263 33.1 About the Project .......................................................................................................................... 263 33.2 Creating the ViewModel Example Project................................................................................. 263 33.3 Reviewing the Project................................................................................................................... 264 33.3.1 The Main Activity................................................................................................................... 264 33.3.2 The Content Fragment .......................................................................................................... 264 33.3.3 The ViewModel ...................................................................................................................... 266 33.4 Designing the Fragment Layout.................................................................................................. 266 33.5 Implementing the View Model.................................................................................................... 267 33.6 Associating the Fragment with the View Model....................................................................... 267 33.7 Modifying the Fragment .............................................................................................................. 268 33.8 Accessing the ViewModel Data................................................................................................... 269 33.9 Testing the Project......................................................................................................................... 270 33.10 Summary ...................................................................................................................................... 270 34. An Android Jetpack LiveData Tutorial................................................................................................ 271 34.1 LiveData - A Recap ....................................................................................................................... 271 34.2 Adding LiveData to the ViewModel........................................................................................... 271 34.3 Implementing the Observer......................................................................................................... 273 34.4 Summary ........................................................................................................................................ 275 35. An Overview of Android Jetpack Data Binding .................................................................................. 277 35.1 An Overview of Data Binding..................................................................................................... 277 35.2 The Key Components of Data Binding ...................................................................................... 277 35.2.1 The Project Build Configuration.......................................................................................... 277 35.2.2 The Data Binding Layout File............................................................................................... 278 35.2.3 The Layout File Data Element .............................................................................................. 279 35.2.4 The Binding Classes.............................................................................................................. 280 35.2.5 Data Binding Variable Configuration.................................................................................. 280 35.2.6 Binding Expressions (One-Way).......................................................................................... 281 35.2.7 Binding Expressions (Two-Way).......................................................................................... 282 35.2.8 Event and Listener Bindings................................................................................................. 282 35.3 Summary ........................................................................................................................................ 283 36. An Android Jetpack Data Binding Tutorial......................................................................................... 285 36.1 Removing the Redundant Code.................................................................................................. 285 36.2 Enabling Data Binding ................................................................................................................. 287 36.3 Adding the Layout Element......................................................................................................... 287 36.4 Adding the Data Element to Layout File.................................................................................... 288 36.5 Working with the Binding Class ................................................................................................. 288 36.6 Assigning the ViewModel Instance to the Data Binding Variable ......................................... 289 36.7 Adding Binding Expressions ....................................................................................................... 290 36.8 Adding the Conversion Method ................................................................................................. 291 36.9 Adding a Listener Binding ........................................................................................................... 291 36.10 Testing the App............................................................................................................................ 291 36.11 Summary ...................................................................................................................................... 292 37. An Android ViewModel Saved State Tutorial...................................................................................... 293 x Table of Contents 37.1 Understanding ViewModel State Saving.................................................................................... 293 37.2 Implementing ViewModel State Saving ..................................................................................... 294 37.3 Saving and Restoring State........................................................................................................... 295 37.4 Adding Saved State Support to the ViewModelDemo Project................................................ 295 37.5 Summary ........................................................................................................................................ 297 38. Working with Android Lifecycle-Aware Components........................................................................ 299 38.1 Lifecycle Awareness ...................................................................................................................... 299 38.2 Lifecycle Owners........................................................................................................................... 299 38.3 Lifecycle Observers....................................................................................................................... 300 38.4 Lifecycle States and Events........................................................................................................... 301 38.5 Summary ........................................................................................................................................ 302 39. An Android Jetpack Lifecycle Awareness Tutorial .............................................................................. 303 39.1 Creating the Example Lifecycle Project...................................................................................... 303 39.2 Creating a Lifecycle Observer...................................................................................................... 303 39.3 Adding the Observer .................................................................................................................... 304 39.4 Testing the Observer..................................................................................................................... 305 39.5 Creating a Lifecycle Owner.......................................................................................................... 305 39.6 Testing the Custom Lifecycle Owner.......................................................................................... 307 39.7 Summary ........................................................................................................................................ 308 40. An Overview of the Navigation Architecture Component.................................................................. 309 40.1 Understanding Navigation........................................................................................................... 309 40.2 Declaring a Navigation Host........................................................................................................ 310 40.3 The Navigation Graph .................................................................................................................. 312 40.4 Accessing the Navigation Controller.......................................................................................... 313 40.5 Triggering a Navigation Action................................................................................................... 313 40.6 Passing Arguments........................................................................................................................ 314 40.7 Summary ........................................................................................................................................ 314 41. An Android Jetpack Navigation Component Tutorial ........................................................................ 315 41.1 Creating the NavigationDemo Project....................................................................................... 315 41.2 Adding Navigation to the Build Configuration......................................................................... 315 41.3 Creating the Navigation Graph Resource File........................................................................... 316 41.4 Declaring a Navigation Host........................................................................................................ 317 41.5 Adding Navigation Destinations................................................................................................. 319 41.6 Designing the Destination Fragment Layouts........................................................................... 320 41.7 Adding an Action to the Navigation Graph............................................................................... 321 41.8 Implement the OnFragmentInteractionListener...................................................................... 323 41.9 Adding View Binding Support to the Destination Fragments................................................ 324 41.10 Triggering the Action ................................................................................................................. 325 41.11 Passing Data Using Safeargs...................................................................................................... 325 41.12 Summary ...................................................................................................................................... 329 42. An Introduction to MotionLayout....................................................................................................... 331 42.1 An Overview of MotionLayout................................................................................................... 331 42.2 MotionLayout................................................................................................................................331 42.3 MotionScene .................................................................................................................................. 331 42.4 Configuring ConstraintSets......................................................................................................... 332 42.5 Custom Attributes......................................................................................................................... 333 xi Table of Contents 42.6 Triggering an Animation.............................................................................................................. 334 42.7 Arc Motion..................................................................................................................................... 336 42.8 Keyframes....................................................................................................................................... 336 42.8.1 Attribute Keyframes............................................................................................................... 336 42.8.2 Position Keyframes................................................................................................................ 337 42.9 Time Linearity ............................................................................................................................... 340 42.10 KeyTrigger.................................................................................................................................... 341 42.11 Cycle and Time Cycle Keyframes ............................................................................................. 341 42.12 Starting an Animation from Code............................................................................................ 341 43. An Android MotionLayout Editor Tutorial......................................................................................... 343 43.1 Creating the MotionLayoutDemo Project................................................................................. 343 43.2 ConstraintLayout to MotionLayout Conversion ...................................................................... 343 43.3 Configuring Start and End Constraints..................................................................................... 345 43.4 Previewing the MotionLayout Animation................................................................................. 347 43.5 Adding an OnClick Gesture ........................................................................................................ 348 43.6 Adding an Attribute Keyframe to the Transition...................................................................... 349 43.7 Adding a CustomAttribute to a Transition................................................................................ 352 43.8 Adding Position Keyframes......................................................................................................... 353 43.9 Summary ........................................................................................................................................ 356 44. A MotionLayout KeyCycle Tutorial ..................................................................................................... 357 44.1 An Overview of Cycle Keyframes............................................................................................... 357 44.2 Using the Cycle Editor.................................................................................................................. 361 44.3 Creating the KeyCycleDemo Project.......................................................................................... 362 44.4 Configuring the Start and End Constraints............................................................................... 362 44.5 Creating the Cycles ....................................................................................................................... 364 44.6 Previewing the Animation........................................................................................................... 366 44.7 Adding the KeyFrameSet to the MotionScene .......................................................................... 366 44.8 Summary ........................................................................................................................................ 368 45. Working with the Floating Action Button and Snackbar .................................................................... 369 45.1 The Material Design...................................................................................................................... 369 45.2 The Design Library ....................................................................................................................... 369 45.3 The Floating Action Button (FAB) ............................................................................................. 369 45.4 The Snackbar.................................................................................................................................. 370 45.5 Creating the Example Project...................................................................................................... 371 45.6 Reviewing the Project................................................................................................................... 371 45.7 Removing Navigation Features....................................................................................................372 45.8 Changing the Floating Action Button ........................................................................................ 373 45.9 Adding an Action to the Snackbar.............................................................................................. 374 45.10 Summary ...................................................................................................................................... 374 46. Creating a Tabbed Interface using the TabLayout Component .......................................................... 377 46.1 An Introduction to the ViewPager2 ........................................................................................... 377 46.2 An Overview of the TabLayout Component ............................................................................. 377 46.3 Creating the TabLayoutDemo Project........................................................................................ 378 46.4 Creating the First Fragment......................................................................................................... 379 46.5 Duplicating the Fragments...........................................................................................................380 46.6 Adding the TabLayout and ViewPager2..................................................................................... 381 46.7 Creating the Pager Adapter.......................................................................................................... 382 xii Table of Contents 46.8 Performing the Initialization Tasks............................................................................................. 383 46.9 Testing the Application................................................................................................................. 385 46.10 Customizing the TabLayout....................................................................................................... 385 46.11 Summary ...................................................................................................................................... 386 47. Working with the RecyclerView and CardView Widgets.................................................................... 389 47.1 An Overview of the RecyclerView.............................................................................................. 389 47.2 An Overview of the CardView.................................................................................................... 391 47.3 Summary ........................................................................................................................................ 392 48. An Android RecyclerView and CardView Tutorial............................................................................. 393 48.1 Creating the CardDemo Project..................................................................................................393 48.2 Modifying the Basic Activity Project.......................................................................................... 393 48.3 Designing the CardView Layout................................................................................................. 394 48.4 Adding the RecyclerView............................................................................................................. 395 48.5 Adding the Image Files................................................................................................................. 395 48.6 Creating the RecyclerView Adapter............................................................................................ 396 48.7 Initializing the RecyclerView Component................................................................................. 398 48.8 Testing the Application................................................................................................................. 399 48.9 Responding to Card Selections....................................................................................................400 48.10 Summary ...................................................................................................................................... 401 49. A Layout Editor Sample Data Tutorial ................................................................................................ 403 49.1 Adding Sample Data to a Project................................................................................................ 403 49.2 Using Custom Sample Data ......................................................................................................... 407 49.3 Summary ........................................................................................................................................ 410 50. Working with the AppBar and Collapsing Toolbar Layouts............................................................... 411 50.1 The Anatomy of an AppBar......................................................................................................... 411 50.2 The Example Project..................................................................................................................... 412 50.3 Coordinating the RecyclerView and Toolbar............................................................................ 412 50.4 Introducing the Collapsing Toolbar Layout .............................................................................. 414 50.5 Changing the Title and Scrim Color .......................................................................................... 417 50.6 Summary ........................................................................................................................................ 418 51. An Android Studio Primary/Detail Flow Tutorial.............................................................................. 419 51.1 The Primary/Detail Flow.............................................................................................................. 419 51.2 Creating a Primary/Detail Flow Activity ................................................................................... 420 51.3 Modifying the Primary/Detail Flow Template.......................................................................... 421 51.4 Changing the Content Model...................................................................................................... 421 51.5 Changing the Detail Pane ............................................................................................................ 423 51.6 Modifying the WebsiteDetailFragment Class............................................................................ 424 51.7 Modifying the WebsiteListFragment Class................................................................................ 425 51.8 Adding Manifest Permissions...................................................................................................... 426 51.9 Running the Application.............................................................................................................. 426 51.10 Summary ...................................................................................................................................... 426 52. An Overview of Android Intents ......................................................................................................... 427 52.1 An Overview of Intents................................................................................................................ 427 52.2 Explicit Intents............................................................................................................................... 427 52.3 Returning Data from an Activity ................................................................................................ 428 52.4 Implicit Intents .............................................................................................................................. 429 xiii Table of Contents 52.5 Using Intent Filters........................................................................................................................ 430 52.6 Automatic Link Verification ........................................................................................................ 431 52.7 Manually Enabling Links ............................................................................................................. 433 52.8 Checking Intent Availability ........................................................................................................ 435 52.9 Summary ........................................................................................................................................ 435 53. Android Explicit Intents – A Worked Example................................................................................... 437 53.1 Creating the Explicit Intent Example Application.................................................................... 437 53.2 Designing the User Interface Layout for MainActivity............................................................ 437 53.3 Creating the Second Activity Class............................................................................................. 438 53.4 Designing the User Interface Layout for SecondActivity ........................................................ 439 53.5 Reviewing the Application Manifest File ................................................................................... 439 53.6 Creating the Intent........................................................................................................................ 440 53.7 Extracting Intent Data .................................................................................................................. 441 53.8 Launching SecondActivity as a Sub-Activity............................................................................. 442 53.9 Returning Data from a Sub-Activity...........................................................................................443 53.10 Testing the Application...............................................................................................................443 53.11 Summary ...................................................................................................................................... 443 54. Android Implicit Intents – A Worked Example .................................................................................. 445 54.1 Creating the Android Studio Implicit Intent Example Project ............................................... 445 54.2 Designing the User Interface ....................................................................................................... 445 54.3 Creating the Implicit Intent ......................................................................................................... 446 54.4 Adding a Second Matching Activity........................................................................................... 447 54.5 Adding the Web View to the UI.................................................................................................. 447 54.6 Obtaining the Intent URL............................................................................................................ 448 54.7 Modifying the MyWebView Project Manifest File ................................................................... 449 54.8 Installing the MyWebView Package on a Device...................................................................... 450 54.9 Testing the Application................................................................................................................. 451 54.10 Manually Enabling the Link ...................................................................................................... 451 54.11 Automatic Link Verification...................................................................................................... 453 54.12 Summary ...................................................................................................................................... 455 55. Android Broadcast Intents and Broadcast Receivers.......................................................................... 457 55.1 An Overview of Broadcast Intents.............................................................................................. 457 55.2 An Overview of Broadcast Receivers ......................................................................................... 458 55.3 Obtaining Results from a Broadcast........................................................................................... 459 55.4 Sticky Broadcast Intents............................................................................................................... 459 55.5 The Broadcast Intent Example..................................................................................................... 460 55.6 Creating the Example Application.............................................................................................. 460 55.7 Creating and Sending the Broadcast Intent............................................................................... 460 55.8 Creating the Broadcast Receiver................................................................................................. 461 55.9 Registering the Broadcast Receiver............................................................................................. 462 55.10 Testing the Broadcast Example ................................................................................................. 463 55.11 Listening for System Broadcasts................................................................................................ 463 55.12 Summary ...................................................................................................................................... 464 56. A Basic Overview of Java Threads, Handlers and Executors............................................................... 465 56.1 An Overview of Threads .............................................................................................................. 465 56.2 The Application Main Thread...................................................................................................... 465 56.3 Thread Handlers............................................................................................................................ 465 xiv Table of Contents 56.4 A Threading Example ................................................................................................................... 465 56.5 Building the App ........................................................................................................................... 466 56.6 Creating a New Thread................................................................................................................. 467 56.7 Implementing a Thread Handler................................................................................................. 468 56.8 Passing a Message to the Handler............................................................................................... 469 56.9 Java Executor Concurrency ......................................................................................................... 470 56.10 Working with Runnable Tasks................................................................................................... 471 56.11 Shutting down an Executor Service.......................................................................................... 472 56.12 Working with Callable Tasks and Futures ............................................................................... 472 56.13 Handling a Future Result ........................................................................................................... 474 56.14 Scheduling Tasks......................................................................................................................... 475 56.15 Summary ...................................................................................................................................... 476 57. An Overview of Android Services........................................................................................................ 477 57.1 Started Services.............................................................................................................................. 477 57.2 Intent Service ................................................................................................................................. 477 57.3 Bound Service................................................................................................................................ 478 57.4 The Anatomy of a Service ............................................................................................................ 478 57.5 Controlling Destroyed Service Restart Options........................................................................ 479 57.6 Declaring a Service in the Manifest File..................................................................................... 479 57.7 Starting a Service Running on System Startup.......................................................................... 480 57.8 Summary ........................................................................................................................................ 480 58. Implementing an Android Started Service – A Worked Example ...................................................... 481 58.1 Creating the Example Project...................................................................................................... 481 58.2 Designing the User Interface ....................................................................................................... 481 58.3 Creating the Service Class............................................................................................................ 481 58.4 Adding the Service to the Manifest File ..................................................................................... 483 58.5 Starting the Service ....................................................................................................................... 483 58.6 Testing the IntentService Example.............................................................................................. 484 58.7 Using the Service Class................................................................................................................. 484 58.8 Creating the New Service............................................................................................................. 485 58.9 Launching the Service .................................................................................................................. 486 58.10 Running the Application............................................................................................................ 486 58.11 Adding Threading to the Service .............................................................................................. 487 58.12 Summary ...................................................................................................................................... 488 59. Android Local Bound Services – A Worked Example......................................................................... 489 59.1 Understanding Bound Services................................................................................................... 489 59.2 Bound Service Interaction Options............................................................................................ 489 59.3 A Local Bound Service Example................................................................................................. 489 59.4 Adding a Bound Service to the Project...................................................................................... 490 59.5 Implementing the Binder............................................................................................................. 490 59.6 Binding the Client to the Service ................................................................................................ 493 59.7 Completing the Example.............................................................................................................. 494 59.8 Testing the Application................................................................................................................. 495 59.9 Summary ........................................................................................................................................ 495 60. Android Remote Bound Services – A Worked Example ..................................................................... 497 60.1 Client to Remote Service Communication................................................................................ 497 60.2 Creating the Example Application.............................................................................................. 497 xv Table of Contents 60.3 Designing the User Interface ....................................................................................................... 497 60.4 Implementing the Remote Bound Service................................................................................. 498 60.5 Configuring a Remote Service in the Manifest File.................................................................. 499 60.6 Launching and Binding to the Remote Service......................................................................... 500 60.7 Sending a Message to the Remote Service ................................................................................. 501 60.8 Summary ........................................................................................................................................ 502 61. An Android Notifications Tutorial ...................................................................................................... 503 61.1 An Overview of Notifications...................................................................................................... 503 61.2 Creating the NotifyDemo Project............................................................................................... 505 61.3 Designing the User Interface ....................................................................................................... 505 61.4 Creating the Second Activity....................................................................................................... 505 61.5 Creating a Notification Channel ................................................................................................. 506 61.6 Creating and Issuing a Notification............................................................................................ 508 61.7 Launching an Activity from a Notification................................................................................ 510 61.8 Adding Actions to a Notification ................................................................................................ 512 61.9 Bundled Notifications................................................................................................................... 512 61.10 Summary ...................................................................................................................................... 514 62. An Android Direct Reply Notification Tutorial .................................................................................. 517 62.1 Creating the DirectReply Project................................................................................................ 517 62.2 Designing the User Interface ....................................................................................................... 517 62.3 Creating the Notification Channel.............................................................................................. 518 62.4 Building the RemoteInput Object............................................................................................... 519 62.5 Creating the PendingIntent.......................................................................................................... 520 62.6 Creating the Reply Action............................................................................................................ 520 62.7 Receiving Direct Reply Input....................................................................................................... 523 62.8 Updating the Notification ............................................................................................................ 524 62.9 Summary ........................................................................................................................................ 525 63. Foldable Devices and Multi-Window Support ................................................................................... 527 63.1 Foldables and Multi-Window Support....................................................................................... 527 63.2 Using a Foldable Emulator........................................................................................................... 528 63.3 Entering Multi-Window Mode ................................................................................................... 529 63.4 Enabling and using Freeform Support ....................................................................................... 530 63.5 Checking for Freeform Support.................................................................................................. 530 63.6 Enabling Multi-Window Support in an App............................................................................. 530 63.7 Specifying Multi-Window Attributes......................................................................................... 531 63.8 Detecting Multi-Window Mode in an Activity......................................................................... 532 63.9 Receiving Multi-Window Notifications..................................................................................... 532 63.10 Launching an Activity in Multi-Window Mode ..................................................................... 533 63.11 Configuring Freeform Activity Size and Position................................................................... 533 63.12 Summary ...................................................................................................................................... 534 64. An Overview of Android SQLite Databases........................................................................................ 535 64.1 Understanding Database Tables.................................................................................................. 535 64.2 Introducing Database Schema .................................................................................................... 535 64.3 Columns and Data Types ............................................................................................................ 535 64.4 Database Rows .............................................................................................................................. 536 64.5 Introducing Primary Keys ...........................................................................................................536 64.6 What is SQLite?............................................................................................................................. 536 xvi Table of Contents 64.7 Structured Query Language (SQL)............................................................................................. 536 64.8 Trying SQLite on an Android Virtual Device (AVD) .............................................................. 537 64.9 The Android Room Persistence Library..................................................................................... 539 64.10 Summary ...................................................................................................................................... 539 65. The Android Room Persistence Library .............................................................................................. 541 65.1 Revisiting Modern App Architecture ......................................................................................... 541 65.2 Key Elements of Room Database Persistence............................................................................ 541 65.2.1 Repository ............................................................................................................................... 542 65.2.2 Room Database ...................................................................................................................... 542 65.2.3 Data Access Object (DAO)................................................................................................... 542 65.2.4 Entities..................................................................................................................................... 542 65.2.5 SQLite Database ..................................................................................................................... 542 65.3 Understanding Entities................................................................................................................. 543 65.4 Data Access Objects...................................................................................................................... 546 65.5 The Room Database...................................................................................................................... 547 65.6 The Repository............................................................................................................................... 548 65.7 In-Memory Databases.................................................................................................................. 549 65.8 Database Inspector........................................................................................................................ 549 65.9 Summary ........................................................................................................................................ 549 66. An Android TableLayout and TableRow Tutorial ............................................................................... 551 66.1 The TableLayout and TableRow Layout Views.......................................................................... 551 66.2 Creating the Room Database Project ......................................................................................... 552 66.3 Converting to a LinearLayout......................................................................................................552 66.4 Adding the TableLayout to the User Interface........................................................................... 553 66.5 Configuring the TableRows ......................................................................................................... 554 66.6 Adding the Button Bar to the Layout ......................................................................................... 555 66.7 Adding the RecyclerView............................................................................................................. 556 66.8 Adjusting the Layout Margins..................................................................................................... 557 66.9 Summary ........................................................................................................................................ 557 67. An Android Room Database and Repository Tutorial........................................................................ 559 67.1 About the RoomDemo Project.................................................................................................... 559 67.2 Modifying the Build Configuration............................................................................................ 559 67.3 Building the Entity ........................................................................................................................ 560 67.4 Creating the Data Access Object................................................................................................. 561 67.5 Adding the Room Database......................................................................................................... 562 67.6 Adding the Repository ................................................................................................................. 563 67.7 Modifying the ViewModel........................................................................................................... 566 67.8 Creating the Product Item Layout .............................................................................................. 567 67.9 Adding the RecyclerView Adapter.............................................................................................. 568 67.10 Preparing the Main Fragment................................................................................................... 569 67.11 Adding the Button Listeners...................................................................................................... 570 67.12 Adding LiveData Observers ...................................................................................................... 572 67.13 Initializing the RecyclerView..................................................................................................... 573 67.14 Testing the RoomDemo App..................................................................................................... 573 67.15 Using the Database Inspector.................................................................................................... 573 67.16 Summary ...................................................................................................................................... 574 68. Accessing Cloud Storage using the Android Storage Access Framework........................................... 575 xvii Table of Contents 68.1 The Storage Access Framework................................................................................................... 575 68.2 Working with the Storage Access Framework.......................................................................... 576 68.3 Filtering Picker File Listings........................................................................................................ 576 68.4 Handling Intent Results................................................................................................................ 577 68.5 Reading the Content of a File ...................................................................................................... 577 68.6 Writing Content to a File ............................................................................................................. 578 68.7 Deleting a File................................................................................................................................ 579 68.8 Gaining Persistent Access to a File..............................................................................................579 68.9 Summary ........................................................................................................................................ 579 69. An Android Storage Access Framework Example ............................................................................... 581 69.1 About the Storage Access Framework Example........................................................................ 581 69.2 Creating the Storage Access Framework Example.................................................................... 581 69.3 Designing the User Interface ....................................................................................................... 581 69.4 Adding the Activity Launchers.................................................................................................... 582 69.5 Creating a New Storage File......................................................................................................... 584 69.6 Saving to a Storage File................................................................................................................. 586 69.7 Opening and Reading a Storage File .......................................................................................... 587 69.8 Testing the Storage Access Application...................................................................................... 588 69.9 Summary ........................................................................................................................................ 589 70. Video Playback on Android using the VideoView and MediaController Classes.............................. 591 70.1 Introducing the Android VideoView Class............................................................................... 591 70.2 Introducing the Android MediaController Class..................................................................... 592 70.3 Creating the Video Playback Example ....................................................................................... 592 70.4 Designing the VideoPlayer Layout ............................................................................................. 592 70.5 Downloading the Video File........................................................................................................ 593 70.6 Configuring the VideoView......................................................................................................... 593 70.7 Adding the MediaController to the Video View....................................................................... 595 70.8 Setting up the onPreparedListener ............................................................................................. 596 70.9 Summary ........................................................................................................................................ 597 71. Android Picture-in-Picture Mode........................................................................................................ 599 71.1 Picture-in-Picture Features.......................................................................................................... 599 71.2 Enabling Picture-in-Picture Mode.............................................................................................. 600 71.3 Configuring Picture-in-Picture Parameters .............................................................................. 600 71.4 Entering Picture-in-Picture Mode .............................................................................................. 601 71.5 Detecting Picture-in-Picture Mode Changes............................................................................ 601 71.6 Adding Picture-in-Picture Actions............................................................................................. 602 71.7 Summary ........................................................................................................................................ 602 72. An Android Picture-in-Picture Tutorial.............................................................................................. 605 72.1 Adding Picture-in-Picture Support to the Manifest................................................................. 605 72.2 Adding a Picture-in-Picture Button ........................................................................................... 605 72.3 Entering Picture-in-Picture Mode .............................................................................................. 605 72.4 Detecting Picture-in-Picture Mode Changes............................................................................ 607 72.5 Adding a Broadcast Receiver....................................................................................................... 608 72.6 Adding the PiP Action.................................................................................................................. 609 72.7 Testing the Picture-in-Picture Action ........................................................................................ 611 72.8 Summary ........................................................................................................................................ 612 73. Making Runtime Permission Requests in Android............................................................................. 613 xviii Table of Contents 73.1 Understanding Normal and Dangerous Permissions............................................................... 613 73.2 Creating the Permissions Example Project................................................................................ 615 73.3 Checking for a Permission........................................................................................................... 615 73.4 Requesting Permission at Runtime............................................................................................. 617 73.5 Providing a Rationale for the Permission Request ................................................................... 618 73.6 Testing the Permissions App........................................................................................................ 620 73.7 Summary ........................................................................................................................................ 620 74. Android Audio Recording and Playback using MediaPlayer and MediaRecorder ............................ 621 74.1 Playing Audio ................................................................................................................................ 621 74.2 Recording Audio and Video using the MediaRecorder Class................................................. 622 74.3 About the Example Project.......................................................................................................... 623 74.4 Creating the AudioApp Project................................................................................................... 623 74.5 Designing the User Interface ....................................................................................................... 623 74.6 Checking for Microphone Availability....................................................................................... 624 74.7 Initializing the Activity................................................................................................................. 625 74.8 Implementing the recordAudio() Method................................................................................. 626 74.9 Implementing the stopAudio() Method..................................................................................... 627 74.10 Implementing the playAudio() method................................................................................... 627 74.11 Configuring and Requesting Permissions ............................................................................... 627 74.12 Testing the Application...............................................................................................................630 74.13 Summary ...................................................................................................................................... 630 75. Working with the Google Maps Android API in Android Studio ...................................................... 631 75.1 The Elements of the Google Maps Android API ...................................................................... 631 75.2 Creating the Google Maps Project.............................................................................................. 632 75.3 Obtaining Your Developer Signature ......................................................................................... 632 75.4 Adding the Apache HTTP Legacy Library Requirement........................................................ 633 75.5 Testing the Application................................................................................................................. 633 75.6 Understanding Geocoding and Reverse Geocoding ................................................................ 634 75.7 Adding a Map to an Application................................................................................................. 636 75.8 Requesting Current Location Permission.................................................................................. 636 75.9 Displaying the User’s Current Location ..................................................................................... 637 75.10 Changing the Map Type............................................................................................................. 638 75.11 Displaying Map Controls to the User....................................................................................... 639 75.12 Handling Map Gesture Interaction........................................................................................... 640 75.12.1 Map Zooming Gestures....................................................................................................... 640 75.12.2 Map Scrolling/Panning Gestures....................................................................................... 640 75.12.3 Map Tilt Gestures................................................................................................................. 641 75.12.4 Map Rotation Gestures........................................................................................................ 641 75.13 Creating Map Markers................................................................................................................ 641 75.14 Controlling the Map Camera .................................................................................................... 642 75.15 Summary ...................................................................................................................................... 643 76. Printing with the Android Printing Framework ................................................................................. 645 76.1 The Android Printing Architecture ............................................................................................ 645 76.2 The Print Service Plugins............................................................................................................. 645 76.3 Google Cloud Print....................................................................................................................... 646 76.4 Printing to Google Drive.............................................................................................................. 646 76.5 Save as PDF.................................................................................................................................... 647 76.6 Printing from Android Devices .................................................................................................. 647 xix Table of Contents 76.7 Options for Building Print Support into Android Apps.......................................................... 648 76.7.1 Image Printing........................................................................................................................ 648 76.7.2 Creating and Printing HTML Content ............................................................................... 649 76.7.3 Printing a Web Page............................................................................................................... 650 76.7.4 Printing a Custom Document.............................................................................................. 651 76.8 Summary ........................................................................................................................................ 651 77. An Android HTML and Web Content Printing Example ................................................................... 653 77.1 Creating the HTML Printing Example Application................................................................. 653 77.2 Printing Dynamic HTML Content............................................................................................. 653 77.3 Creating the Web Page Printing Example.................................................................................. 656 77.4 Removing the Floating Action Button ....................................................................................... 656 77.5 Removing Navigation Features....................................................................................................656 77.6 Designing the User Interface Layout.......................................................................................... 658 77.7 Accessing the WebView from the Main Activity ...................................................................... 658 77.8 Loading the Web Page into the WebView.................................................................................. 659 77.9 Adding the Print Menu Option................................................................................................... 660 77.10 Summary ...................................................................................................................................... 661 78. A Guide to Android Custom Document Printing............................................................................... 663 78.1 An Overview of Android Custom Document Printing ........................................................... 663 78.1.1 Custom Print Adapters.......................................................................................................... 663 78.2 Preparing the Custom Document Printing Project.................................................................. 664 78.3 Creating the Custom Print Adapter............................................................................................ 665 78.4 Implementing the onLayout() Callback Method...................................................................... 666 78.5 Implementing the onWrite() Callback Method ........................................................................ 669 78.6 Checking a Page is in Range ........................................................................................................ 671 78.7 Drawing the Content on the Page Canvas................................................................................. 672 78.8 Starting the Print Job .................................................................................................................... 674 78.9 Testing the Application................................................................................................................. 675 78.10 Summary ...................................................................................................................................... 675 79. An Introduction to Android App Links............................................................................................... 677 79.1 An Overview of Android App Links.......................................................................................... 677 79.2 App Link Intent Filters................................................................................................................. 677 79.3 Handling App Link Intents.......................................................................................................... 678 79.4 Associating the App with a Website............................................................................................678 79.5 Summary ........................................................................................................................................ 679 80. An Android Studio App Links Tutorial ............................................................................................... 681 80.1 About the Example App ............................................................................................................... 681 80.2 The Database Schema ................................................................................................................... 681 80.3 Loading and Running the Project............................................................................................... 682 80.4 Adding the URL Mapping............................................................................................................ 683 80.5 Adding the Intent Filter................................................................................................................ 686 80.6 Adding Intent Handling Code..................................................................................................... 686 80.7 Testing the App.............................................................................................................................. 689 80.8 Creating the Digital Asset Links File.......................................................................................... 689 80.9 Testing the App Link..................................................................................................................... 690 80.10 Summary ...................................................................................................................................... 690 81. An Android Biometric Authentication Tutorial.................................................................................. 691 xx Table of Contents 81.1 An Overview of Biometric Authentication................................................................................ 691 81.2 Creating the Biometric Authentication Project ........................................................................ 691 81.3 Configuring Device Fingerprint Authentication ...................................................................... 692 81.4 Adding the Biometric Permission to the Manifest File............................................................ 692 81.5 Designing the User Interface ....................................................................................................... 693 81.6 Adding a Toast Convenience Method........................................................................................ 693 81.7 Checking the Security Settings.................................................................................................... 694 81.8 Configuring the Authentication Callbacks................................................................................ 695 81.9 Adding the CancellationSignal.................................................................................................... 696 81.10 Starting the Biometric Prompt.................................................................................................. 697 81.11 Testing the Project....................................................................................................................... 697 81.12 Summary ...................................................................................................................................... 698 82. Creating, Testing and Uploading an Android App Bundle................................................................. 699 82.1 The Release Preparation Process................................................................................................. 699 82.2 Android App Bundles................................................................................................................... 699 82.3 Register for a Google Play Developer Console Account.......................................................... 700 82.4 Configuring the App in the Console .......................................................................................... 701 82.5 Enabling Google Play App Signing............................................................................................. 702 82.6 Creating a Keystore File ............................................................................................................... 702 82.7 Creating the Android App Bundle.............................................................................................. 704 82.8 Generating Test APK Files........................................................................................................... 705 82.9 Uploading the App Bundle to the Google Play Developer Console....................................... 706 82.10 Exploring the App Bundle ......................................................................................................... 707 82.11 Managing Testers ........................................................................................................................ 709 82.12 Rolling the App Out for Testing................................................................................................ 709 82.13 Uploading New App Bundle Revisions.................................................................................... 709 82.14 Analyzing the App Bundle File ................................................................................................. 710 82.15 Summary ...................................................................................................................................... 711 83. An Overview of Android Dynamic Feature Modules.......................................................................... 713 83.1 An Overview of Dynamic Feature Modules.............................................................................. 713 83.2 Dynamic Feature Module Architecture ..................................................................................... 713 83.3 Creating a Dynamic Feature Module ......................................................................................... 714 83.4 Converting an Existing Module for Dynamic Delivery........................................................... 716 83.5 Working with Dynamic Feature Modules.................................................................................. 719 83.6 Handling Large Dynamic Feature Modules .............................................................................. 721 83.7 Summary ........................................................................................................................................ 722 84. An Android Studio Dynamic Feature Tutorial.................................................................................... 723 84.1 Creating the DynamicFeature Project........................................................................................ 723 84.2 Adding Dynamic Feature Support to the Project ..................................................................... 723 84.3 Designing the Base Activity User Interface ............................................................................... 724 84.4 Adding the Dynamic Feature Module........................................................................................ 725 84.5 Reviewing the Dynamic Feature Module................................................................................... 726 84.6 Adding the Dynamic Feature Activity........................................................................................ 727 84.7 Implementing the launchIntent() Method................................................................................. 730 84.8 Uploading the App Bundle for Testing....................................................................................... 731 84.9 Implementing the installFeature() Method ............................................................................... 732 84.10 Adding the Update Listener....................................................................................................... 734 84.11 Using Deferred Installation ....................................................................................................... 737 xxi Table of Contents 84.12 Removing a Dynamic Module .................................................................................................. 737 84.13 Summary ...................................................................................................................................... 737 85. Working with Material Design 3 Theming .......................................................................................... 739 85.1 Material Design 2 vs Material Design 3 ..................................................................................... 739 85.2 Understanding Material Design Theming ................................................................................. 739 85.3 Material Design 2 Theming ......................................................................................................... 739 85.4 Material Design 3 Theming ......................................................................................................... 741 85.5 Building a Custom Theme............................................................................................................742 85.6 Summary ........................................................................................................................................ 743 86. A Material Design 3 Theming and Dynamic Color Tutorial............................................................... 745 86.1 Creating the ThemeDemo Project .............................................................................................. 745 86.2 Designing the User Interface ....................................................................................................... 745 86.3 Migrating to Material Design 3................................................................................................... 747 86.4 Building a New Theme ................................................................................................................. 748 86.5 Adding the Theme to the Project................................................................................................ 749 86.6 Enabling Dynamic Color Support .............................................................................................. 750 86.7 Summary ........................................................................................................................................ 751 87. An Overview of Gradle in Android Studio.......................................................................................... 753 87.1 An Overview of Gradle ................................................................................................................ 753 87.2 Gradle and Android Studio ......................................................................................................... 753 87.2.1 Sensible Defaults .................................................................................................................... 753 87.2.2 Dependencies..........................................................................................................................753 87.2.3 Build Variants......................................................................................................................... 754 87.2.4 Manifest Entries ..................................................................................................................... 754 87.2.5 APK Signing............................................................................................................................ 754 87.2.6 ProGuard Support.................................................................................................................. 754 87.3 The Property and Settings Gradle Build File............................................................................. 754 87.4 The Top-level Gradle Build File................................................................................................... 755 87.5 Module Level Gradle Build Files................................................................................................. 756 87.6 Configuring Signing Settings in the Build File.......................................................................... 758 87.7 Running Gradle Tasks from the Command-line ...................................................................... 759 87.8 Summary ........................................................................................................................................ 759 Index ........................................................................................................................................................... 76