Question

I can register my android app with C2DM successfully using a <receiver> in my manifest. However, if I delete the <receiver> from the manifest and register my receiver using the method registerReceiver of the context, I receive a SERVICE_NOT_AVAILABLE error response. I have reproduced this behaviour in the emulator and in a real device.

Is dynamically registering a C2DM receiver possible?

This is the fragment of the manifest I deleted:

<receiver android:name=".service.C2DM.C2DMReceiver" android:permission="com.google.android.c2dm.permission.SEND">
  <intent-filter>
      <action android:name="com.google.android.c2dm.intent.RECEIVE" />
      <category android:name="mytestapp" />
  </intent-filter>
  <intent-filter>
      <action android:name="com.google.android.c2dm.intent.REGISTRATION" />
      <category android:name="mytestapp" />
  </intent-filter>
</receiver>

And here is the code:

public class C2DMReceiver extends BroadcastReceiver {

    @Override
    public void onReceive(Context context, Intent intent) {
        String registration = intent.getStringExtra("registration_id");
        if (intent.getStringExtra("error") != null) {
            //TODO: Registration failed, should try again later.
            Log.e("MyTestAppC2DM", "C2DM Error = " + intent.getStringExtra("error"));
        } else if (intent.getStringExtra("unregistered") != null) {
            Log.d("MyTestAppC2DM", "C2DM Unregistered");
        } else if (registration != null) {
            Log.d("MyTestAppC2DM","C2DM registration_id = " + registration);
        } else {
            Log.w("MyTestAppC2DM", "C2DM No registration_id");
        }
    }

    public static void register(Context context){
        /* BEGIN OF DYNAMIC REGISTER */
        C2DMReceiver c2dmReceiver = new C2DMReceiver();

        IntentFilter receiveIntentFilter = new IntentFilter();
        receiveIntentFilter.addAction("com.google.android.c2dm.intent.RECEIVE");
        receiveIntentFilter.addCategory("mytestapp");
        context.registerReceiver(c2dmReceiver, receiveIntentFilter, "com.google.android.c2dm.permission.SEND", null);

        IntentFilter registrationIntentFilter = new IntentFilter();
        registrationIntentFilter.addAction("com.google.android.c2dm.intent.REGISTRATION");
        registrationIntentFilter.addCategory("mytestapp");
        context.registerReceiver(c2dmReceiver, registrationIntentFilter, "com.google.android.c2dm.permission.SEND", null);

        /*END OF DYNAMIC REGISTER*/

        Intent registrationIntent = new Intent("com.google.android.c2dm.intent.REGISTER");
        registrationIntent.putExtra("app", PendingIntent.getBroadcast(context, 0, new Intent(), 0));
        registrationIntent.putExtra("sender", "[e-mail]");
        ComponentName service = context.startService(registrationIntent);
        if(service!=null){
            Log.d("MyTestAppC2DM","C2DM Registration sent");
        }else{
            Log.d("MyTestAppC2DM","C2DM Service not found");
        }   
    }
}

Answer 1

When a broadcast is sent by the system it will start applications to handle the intent if they have a matching intent filter declared in the manifest. Due to the nature of C2DM it is not useful to have a Broadcast Receiver installed dynamically because your application might not be running when a C2DM message is received. If its not running it won’t be started for a dynamically installed receiver.