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POUnexpected Application Crash
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copied!<p>I try to create a service-client application ( still learning these ). My application crashes from the beginning and doesnt let me do anything. Any ideas how to figure it out ? Here are my 2 classes and the manifest file.</p> <p>////////////////// 1. MainActivity.java //////////////////////</p> <pre><code>public class MainActivity extends Activity { /** Messenger for communicating with the service. */ Messenger mService = null; /** Flag indicating whether we have called bind on the service. */ boolean mBound; /** * Handler of incoming messages from service. */ static class IncomingHandler extends Handler { private TextView mCallbackText; @Override public void handleMessage(Message msg) { switch (msg.what) { case MessengerService.MSG_SET_VALUE: mCallbackText.setText("Received from service: " + msg.arg1); break; default: super.handleMessage(msg); } } } /** * Target we publish for clients to send messages to IncomingHandler. */ final Messenger mMessenger = new Messenger(new IncomingHandler()); public void sayHello(View v) { if (!mBound) return; // Create and send a message to the service, using a supported 'what' value Message msg = Message.obtain(null, MessengerService.MSG_REGISTER_CLIENT, 0, 0); try { msg.replyTo = mMessenger; mService.send(msg); } catch (RemoteException e) { e.printStackTrace(); } } @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); } @Override protected void onStart() { super.onStart(); // Bind to the service bindService(new Intent(this, MessengerService.class), mConnection, Context.BIND_AUTO_CREATE); mBound = true; } @Override protected void onStop() { super.onStop(); // Unbind from the service if (mBound) { unbindService(mConnection); mBound = false; } } /** * Class for interacting with the main interface of the service. */ private ServiceConnection mConnection = new ServiceConnection() { public void onServiceConnected(ComponentName className, IBinder service) { // This is called when the connection with the service has been // established, giving us the object we can use to // interact with the service. We are communicating with the // service using a Messenger, so here we get a client-side // representation of that from the raw IBinder object. mService = new Messenger(service); mBound = true; /*try { Message msg = Message.obtain(null, MessengerService.MSG_REGISTER_CLIENT); msg.replyTo = mMessenger; mService.send(msg); // Give it some value as an example. msg = Message.obtain(null, MessengerService.MSG_SET_VALUE, this.hashCode(), 0); mService.send(msg); } catch (RemoteException e) { e.printStackTrace(); }*/ } public void onServiceDisconnected(ComponentName className) { // This is called when the connection with the service has been // unexpectedly disconnected -- that is, its process crashed. mService = null; mBound = false; } }; </code></pre> <p>}</p> <p>/////////////////// 2. MessengerService.java ////////////////////////</p> <pre><code>public class MessengerService extends Service { String ns = Context.NOTIFICATION_SERVICE; NotificationManager mNM = (NotificationManager) getSystemService(ns); /** Command to the service to display a message */ static final int MSG_SAY_HELLO = 1; /** Command to the service to register a client */ static final int MSG_REGISTER_CLIENT = 1; /** Command to the service to unregister a client */ static final int MSG_UNREGISTER_CLIENT = 2; /** Command to the service to set a new value */ static final int MSG_SET_VALUE = 3; static class IncomingHandler extends Handler { private ArrayList<Messenger> mClients = new ArrayList<Messenger>(); private int mValue=0; @Override public void handleMessage(Message msg) { switch (msg.what) { case MSG_REGISTER_CLIENT: mClients.add(msg.replyTo); break; case MSG_UNREGISTER_CLIENT: mClients.remove(msg.replyTo); break; case MSG_SET_VALUE: mValue = msg.arg1; for (int i=mClients.size()-1; i>=0; i--) { try { mClients.get(i).send(Message.obtain(null, MSG_SET_VALUE, mValue, 0)); } catch (RemoteException e) { // The client is dead. Remove it from the list; // we are going through the list from back to front // so this is safe to do inside the loop. mClients.remove(i); } } break; default: super.handleMessage(msg); } } } final Messenger mMessenger = new Messenger(new IncomingHandler()); public void onCreate() { mNM = (NotificationManager)getSystemService(NOTIFICATION_SERVICE); // Display a notification about us starting. showNotification(); //handleMessage(msg); } @Override public void onDestroy() { // Cancel the persistent notification. mNM.cancel(R.string.remote_service_started); // Tell the user we stopped. Toast.makeText(this, R.string.remote_service_stopped, Toast.LENGTH_SHORT).show(); } @Override public IBinder onBind(Intent intent) { Toast.makeText(getApplicationContext(), "Binding..", Toast.LENGTH_SHORT).show(); return mMessenger.getBinder(); } private void showNotification() { // Set icon, scrolling text, etc int icon = R.drawable.asd; CharSequence tickerText = "Hello!"; CharSequence text = getText(R.string.remote_service_started); long when = System.currentTimeMillis(); Context context = getApplicationContext(); //Create notication with parameters Notification.Builder nFN = new Notification.Builder(context) .setTicker(tickerText) .setWhen(when) .setSmallIcon(icon) .setContentTitle("Test Notifications") .setContentText(text) .setAutoCancel(true); // The PendingIntent to launch our activity if the user selects this notification PendingIntent contentIntent = PendingIntent.getActivity(this, 0, new Intent(this, MessengerService.class), 0); nFN.setContentIntent(contentIntent); // Send the notification. Notification n = nFN.build(); mNM.notify(R.string.remote_service_started, n); } </code></pre> <p>}</p> <p>/////////////////// 3. Manifest /////////////////////////////////////</p> <pre><code><manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.praktiki.services.messenger" android:versionCode="1" android:versionName="1.0" > <uses-sdk android:minSdkVersion="16" android:targetSdkVersion="15" /> <application android:icon="@drawable/ic_launcher" android:label="@string/app_name" android:theme="@style/AppTheme" > <service android:name=".MessengerService" android:process=":remote" /> <activity android:name=".MainActivity" android:label="@string/title_activity_main" > <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> </application> </code></pre> <p></p>

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