DroidCon 2010

1. Architecture your Android Application Mark Brady

3. 10 Minutes of Q&A

4. Source Code: http://github.com/zedray/Android-Framework-Prototype/

5. Market App Framework Prototype [BETA]

7. Android developer at Vodafone

8. Background in web design, back-end development and Java ME

9. Android Blog: http://blog.zedray.com/category/android/ “ Quick Dial / Call Log Widget”

12. Lack of guidance on how to use them. Service Application Activity

17. Running onStart() - onStop()

18. Finishing onStop() and onDestroy() may not be called if a process is killed (i.e. due to low memory)

20. Do long running work in AsyncTask Separate non-UI thread will avoid ANR error.

22. Code from multiple activities can be running in the background. No good definition for when an application has finished .

30. Singletons

31. Handlers

32. Service binding

34. If you think your application is an exception: “Drag me to Hell - Optimizations for AIDL” Ronan Schwarz, Tic Mobile, 5.30pm. (Android Interface Definition Language)

35. Java Singletons Flip side of running in on process/JVM is that objects in other components can be called as singletons: public class SingletonObject { private static SingletonObject ref; private SingletonObject() { // Do nothing. } public static SingletonObject getSingletonObject() { if (ref == null) { ref = new SingletonObject(); } return ref; } } Calling your singleton SingletonObject obj = SingletonObject.getSingletonObject();

38. Calling Serivce.onBind() will create a Service that will remain running for as long as the ServiceConnection is established, or until a corresponding Service.onUnbind() is called. Service

40. Service binding #3 Bind to this Service: mContext.bindService(new Intent(mContext, MyService.class), mServiceConnection, Context.BIND_AUTO_CREATE); Unbind from this Service: mContext.unbindService(mServiceConnection); Monitor Service Connection: private final ServiceConnection mServiceConnection = new ServiceConnection() { public void onServiceConnected(final ComponentName className, final IBinder service) { mHandler = ((MyService.MyBinder) service).getHandler(); } public void onServiceDisconnected(final ComponentName className) { mHandler = null; } }; Service

42. Source code http://github.com/zedray/Android-Framework-Prototype/

43. Market App Framework Prototype [BETA]

44. Framework #1

45. Framework #2

46. Framework #3

48. State Handled in a single place, so implement database synchronization here.

49. Worker Thread Call stopSelf() as soon as all user goals are complete.

50. Source Code – BaseActivity #1 public class MyActivity extends BaseActivity { @Override public final void onCreate(final Bundle savedInstanceState) { // Database I/O. getCache() .getSomeStateValue(); getDb() .setSomeStateValue("Foo", "Bar"); } @Override protected final void onResume() { // Update the UI on resume. updateUi(); super.onResume(); } ...

51. Source Code – BaseActivity #2 ... public final void doSomeTask() { // Post something to Service queue. getServiceQueue().postToService (Type.DO_SOME_TASK, null); } @Override public final void post (final Type type, final Bundle bundle) { // Implement an incoming UI message, depending on type. switch (type) { case SHOW_SOME_UI: showSomeUi(); break; case UPDATE_UI: updateUi(); break; default: /** Let the BaseActivity handle other message types. */ super.post(type, bundle); break; } } }

52. Source Code – WorkerThread #1 public class WorkerThread extends Thread { public final void run() { while ( mWorkQueue .size() > 0) { synchronized ( mWorkQueue ) { // Remove a task from the queue. Message message = mWorkQueue .remove(0); ... } // Do the task, depending on type. switch (type) { case DO_SOME_TASK: doSomeTask(bundle); break; } } // No work to do, so kill the service. mMyService .stopSelf(); } ...

53. Source Code – WorkerThread #2 ... private void doSomeTask(final Bundle bundle) { mCache .setState("Loading"); mUiQueue . postToUi (Type.UPDATE_UI, null, true); // Do some setup work. ... mCache .setState("Running"); mUiQueue . postToUi (Type.UPDATE_UI, null, true); // Do some real work. ... mCache .setState("Finished"); mUiQueue.postToUi (Type.UPDATE_UI, null, true); if (someCondition) { // Show some custom UI (do not suppress). mUiQueue.postToUi (Type.SHOW_SOME_UI, null, false ); } } }

55. Framework Source http://github.com/zedray/Android-Framework-Prototype/

56. Market App Framework Prototype [BETA]