Android Cookbook

Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xiii
1. Getting Started . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.1 Introduction: Getting Started 1
1.2 Learning the Java Language 1
1.3 Hello World - Command Line 3
1.4 Hello World - Eclipse Version 5
1.5 Set Up an Android Virtual Device for Apps Testing 10
1.6 Set Up an IDE on Windows to Develop for Android 23
1.7 Android Lifecycle 32
1.8 Opening a Web Page, Phone Number or anything else with an Intent 33
1.9 Email Text From a View 35
1.10 Sending an email with attachments 38
1.11 Installing .apk files on the emulator 40
1.12 Installing apps onto an Android Emulator 40
1.13 Android Epoch HTML/Javascript Calendar 43
1.14 Sharing Java classes from another Eclipse Project 48
1.15 Referencing libraries to implement external functionality 49
1.16 Use SDK Samples to Help Avoid Head Scratching 50
1.17 Keeping the Android SDK Updated 55
1.18 Five Ways to Wire Up an Event Listener 61
1.19 Taking a Screenshot from the Emulator/Android Device 69
1.20 Program: A Simple CountDownTimer example 70
1.21 Program: Tipster, a tip calculator for the Android OS 73
2. Designing a successful Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
2.1 Introduction: Designing a Successful Android application 91
2.2 Keeping a Service running while other apps are on display 95
2.3 Starting a service after phone reboot 97
2.4 Exception Handling 98
2.5 Sending/Receive broadcast message 100

2.6 Android's Application Object as a "Singleton" 101
2.7 Keeping data when the user rotates the device 103
2.8 Creating a Responsive Application using Threads 105
2.9 Eating Too Much CPU Time In The UI Causes A Nasty Result 107
2.10 AsyncTask: Do background tasks and modify the GUI 113
2.11 Monitoring the Battery Level of your Android Device 114
2.12 Splash Screens in Android: Method 1 115
2.13 Splash Screens in Android: Method 2 117
2.14 Designing a Conference/*Camp/Hackathon App 123
2.15 Implementing Autocompletion in Android. 124
2.16 Using Google Analytics in Android Application 126
2.17 Using AsyncTask to do background processing 128
2.18 A Simple Torch Light 134
2.19 Adapting Android Phone Application to Tablet 136
2.20 First Run preferences 138
2.21 Formatting the time and date display 139
2.22 Controlling Input with KeyListeners 142
2.23 Android Application Data Backup 145
2.24 Making password fields 151
2.25 Working Without Tooltips: Use Hints Instead 152
3. Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157
3.1 Introduction: Testing 157
3.2 How to TDD(test driven development) Android App 157
3.3 How to troubleshoot "The application has stopped unexpectedly.
Please try again" 158
3.4 Debugging using Log.d and LogCat 161
3.5 Keep Your App Snappy With StrictMode 163
3.6 Barrel of Monkeys 164
3.7 Sending text messages and placing calls between AVDs 165
3.8 Activity LifeCycle Scenarios for Testing 166
4. Content Providers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175
4.1 Introduction: Content Providers 175
4.2 Retrieving Data from a Content Provider 175
4.3 Writing a Content Provider 177
4.4 Android Remote Service 179
5. Graphics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 185
5.1 Introduction: Graphics 185
5.2 Getting Screenshots 185
5.3 Using a Custom Font 186
5.4 Draw a spinning cube with OpenGL ES 191

5.5 Adding control to the OpenGL spinning cube 196
5.6 Taking a Picture Using an Intent 199
5.7 Taking a Picture Using android.media.Camera 201
5.8 Using AndroidPlot to display charts and graphs in your Android
application. 205
5.9 Use Inkscape to Create an Android Launcher Icon 207
5.10 Easy Launcher Icons from OpenClipArt.org using Paint.NET 216
5.11 Android HTML5 RGraph Charting 228
5.12 Simple Raster Animation 232
6. Graphical User Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 239
6.1 Introduction: GUI 239
6.2 User Interface Guidelines (placeholder) 240
6.3 SlidingDrawer Overlapping other UI components 240
6.4 Android 3.0 Photo Gallery 244
6.5 Building a UI using Fragments API of Android 3.0 in Android 2.2 246
6.6 Haptic Feedback 250
6.7 Handling Configuration Changes by Decoupling View from Model 254
6.8 Let Them See Stars: Using RatingBar 257
6.9 Invoke an action handler when a Button is pressed 260
6.10 Creating an Alert Dialog. 263
6.11 Customize the SlidingDrawer component to animate/transition
from the top down. 264
6.12 Use a Timepicker widget 266
6.13 Formatting with Correct Plurals 268
6.14 Feed AutoCompleteTextView using a SQLite database query 272
6.15 Change The Enter Key to "Next" on the Soft Keyboard 273
6.16 How to Create a Simple Widget 277
6.17 Make a View Shake 280
6.18 Using CheckBoxes and RadioButtons 281
6.19 Creating a Notification in the Status Bar 286
6.20 Autocompletion with Icons/Images 288
6.21 Creating your own Custom Title Bar 295
6.22 iPhone-like wheel picker for selection 298
6.23 Simple Calendar 302
6.24 Formatting Numbers 310
6.25 Start a Second Screen from the First 314
6.26 Creating a Tabbed Dialog 322
6.27 Creating a Custom Dialog with buttons, images and text 326
6.28 Create a Custom Menu 328
6.29 Loading Screen in between two Activities 330
6.30 Implementing reactions on click of items in a Custom Menu. 333
6.31 Navigate different activities within a TabView 336

6.32 Drop-down Chooser via the Spinner Class 338
6.33 Effective UI design using Image Buttons 340
6.34 Pinch to zoom 343
6.35 Add a Border with Rounded Corners to a Layout 346
6.36 Creating a ProgressDialog in Android. 347
6.37 Creating a Submenu. 349
6.38 Processing key press events in an Activity. 351
6.39 Constrain EditText Values with Attributes and the TextWatcher
Interface 352
6.40 Gesture Detection in Android 355
6.41 Customizing the Look of a Toast 362
6.42 Using SlidingDrawer to Overlap Other Components 363
7. GUI: ListView . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 367
7.1 Introduction: ListView 367
7.2 Building list-based applications with ListView 367
7.3 'No data' View for Lists 372
7.4 Advanced ListView: populating a list with images and text 373
7.5 ListView with Icons/images 379
7.6 Sectioned Headers in ListViews 386
7.7 Making Lists Behave Nicely 392
7.8 Writing A Custom List Adapter 393
7.9 Orientation Changes : From ListView data values to Landscape
Charting 396
8. Multimedia . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 407
8.1 Introduction: Multimedia 407
8.2 Play a Youtube Video 407
8.3 Using Gallery with ImageSwitcher 408
8.4 Grabbing a video using MediaRecorder 411
8.5 Android Face Detection 414
8.6 Playing audio from a file 417
8.7 Playing Audio without Interaction 420
8.8 Using Speech to Text 421
8.9 Making the Device Speak with TTS 423
9. Data Persistence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 427
9.1 Listing a Directory 427
9.2 Default shared preferences consistency check 429
9.3 Advanced text search 431
9.4 How to push string-values using Intent.putExtra() 437
9.5 Retrieving data from a Sub-Activity back to your Main Activity 439
9.6 Getting total and free space on the SD card 442

9.7 Creating a SQLite database in an Android application. 442
9.8 Retrieving data from a SQLite database. 444
9.9 Inserting values into a SQLite database. 445
9.10 Work With Dates in SQLite 445
9.11 Parsing JSON using the Jackson Parser 448
9.12 Parsing an XML document using the DOM API 451
9.13 Parsing an XML document using an XmlPullParser 453
9.14 Accessing data from a file shipped with the App rather than in the
filesystem 456
9.15 Adding a Contact 457
9.16 Reading Contact Data 461
9.17 Parsing JSON using JSONObject 463
10. Telephone Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 467
10.1 Introduction: Telephone Applications 467
10.2 Do something when the phone rings 467
10.3 Process outgoing calls 471
10.4 Dialing the phone 475
10.5 Sending single or multipart SMS messages 476
10.6 Receiving an SMS in an Android Application. 478
10.7 Using Emulator Controls to send SMS to the Emulator. 480
10.8 Android TelephonyManager. 480
11. Networked Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 491
11.1 Introduction: Networking 491
11.2 Using a RESTful Web Service 491
11.3 Extracting Information from Unstructured Text using Regular
Expressions 494
11.4 Parsing RSS/ATOM feeds parsing with ROME 496
11.5 Using MD5 to Digest Free Text 500
11.6 Converting text into hyperlinks 502
11.7 Accessing a web page through your Android application 503
11.8 Customizing a WebView 505
12. Gaming and Animation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 507
12.1 Introduction: Gaming and Animation 507
12.2 Android Game Programming - Introduction to Flixel-Android 508
12.3 Introduction to Game Programming using AndEngine (Android-
Engine) 510
13. Social Networking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 517
13.1 Facebook Integration 517
13.2 Social Networking Integration using Http 525

13.3 Loading a user's Twitter timeline (using JSON) 528
14. Location and Map Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 533
14.1 Introduction: Location-Aware Applications 533
14.2 Getting Location Information 533
14.3 Access GPS information anywhere in your application 535
14.4 Mocking GPS Coordinates On A Device 537
14.5 Geocoding and Reverse Geocoding 539
14.6 Getting ready for Google Maps development 540
14.7 Using Google Maps in your Android App 547
14.8 How to show your current location in a map 548
14.9 To Add Device's current location to Google Maps 549
14.10 Draw a location marker on a Google MapView 550
14.11 Drawing multiple location markers on a MapView 556
14.12 Creating Overlays for a Google MapView 560
14.13 Changing Views of a MapView. 561
14.14 Draw overlay icon without using Drawable 562
14.15 Location search on Google maps 567
14.16 MapView inside TabView 568
14.17 Handling longpress in a map 572
14.18 Using OpenStreetMap 575
14.19 Creating overlays in OpenStreetMaps 576
14.20 Using a scale on an OpenStreetMap 579
14.21 Handling touch events on an OpenStreetMap Overlay 582
14.22 Getting location updates with OpenStreetMaps 584
15. Accellerometer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 593
15.1 Using the accelerometer to detect shaking of the device 593
15.2 Introduction: Sensors 596
15.3 Checking for device facing up or facing down based on screen
orientation using Accelerometer. 597
15.4 Finding the orientation of an Android device using Orientation
sensor. 598
15.5 Checking for the Presence or Absence of a Sensor 600
15.6 Reading the Temperature Sensor 601
16. Bluetooth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 603
16.1 Introduction: Bluetooth 603
16.2 Connecting to Bluetooth enabled device 603
16.3 Enabling Bluetooth and making the device Discoverable. 606
16.4 Listening for Bluetooth Connection Requests. 607
16.5 Bluetooth Device discovery 609

17. System and Device Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 611
17.1 Phone network/connectivity information 611
17.2 Changing incoming call notification to Silent, Vibrate, or normal 612
17.3 Rebooting the Device 614
17.4 Running shell commands from your application 616
17.5 Copying text and getting text from the Clipboard 617
17.6 Making LED based notifications 619
17.7 Making the Device Vibrate. 620
17.8 Determining Whether a Given Application is Running 621
18. Other Programming Languages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 623
18.1 Run external/native Linux command 623
18.2 Running Adobe Air/Flex on Android 624
18.3 Getting Started with ''Scripting Layer for Android'' (formerly
Android Scripting Environment) 625
18.4 Running Native Code with JNI on the NDK 627
18.5 Introduction: Other Programming Languages 632
18.6 Intro to Flex 4.5 Android Programming 634
18.7 Sharing your scripts (ASE) using QR codes 636
18.8 Using native handset functionality from webview using Javascript 638
19. Internationalization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 641
19.1 Introduction: Internationalization 641
19.2 Internationalizing Application Text 642
20. Packaging, deploying and selling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 647
20.1 Signing Your Application 647
20.2 How to integrate Admob into your app 648
20.3 Distributing Your Application via the Android Market 652
20.4 Creating a Signing Certificate 654
20.5 Obfuscating and Optimizing with ProGuard 657
20.6 Provide a Link to other Published Apps in the Market 660
21. Other . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 663
21.1 Introduction: Everything Else 663
21.2 Sending messages between threads using activity thread queue and
Handler class 663
21.3 Intercommunication amongst Applications 665
22. Contributors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 667
22.1 Names 667