broadcast receiver android

I'm new to android and am desperately with trying to understand how broadcast receivers work. I have built an example which doesn't work, but I cannot imagine why.

My usecase:

When the activity "TestApp" starts, it has to activate a broadcast receiver "Receiver", this one starts another activity "Main" which is defined in the same manifest.

Here's the receiver difinition in my manifest xml

<application android:icon="@drawable/icon" android:label="@string/app_name">
    <activity android:name=".Main"
              android:label="@string/app_name">
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />
            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
        <intent-filter>
            <action android:name="stas.test.intent.action.blablub"/>
            <category android:name="android.intent.category.DEFAULT"/>
        </intent-filter>
        <receiver android:name=".Receiver"
        android:enabled="true">
            <intent-filter>
                <action android:name="stas.test.intent.action.myreceiver"/>
            </intent-filter>
        </receiver>
    </activity>

</application>

this is the activity to be started by the receiver:

action android:name="stas.test.intent.action.blablub" (Main.java)

Here's the receiver's code

public class Receiver extends BroadcastReceiver{
开发者_如何学运维    @Override
    public void onReceive(Context context, Intent intent) {
        Intent newIntent = new Intent();
        newIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
        newIntent.setAction("stas.test.intent.action.blablub");
        newIntent.addCategory("android.intent.category.DEFAULT");
        System.out.println("dd");
        context.startActivity(newIntent);
    }
   }

an here's the initiating activity which calls the receiver

public class TestApp extends Activity {
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        Intent intent = new Intent();
        intent.setAction("stas.test.intent.action.myreceiver");
        getApplicationContext().sendBroadcast(intent);
    }
}

When I start TestApp, Receiver will never start and Main not either.

Haven't tested this, but isn't the receiver supposed to be a child of the application node?

    <application android:icon="@drawable/icon" android:label="@string/app_name">
    <activity android:name=".Main"
              android:label="@string/app_name">
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />
            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
        <intent-filter>
            <action android:name="stas.test.intent.action.blablub"/>
            <category android:name="android.intent.category.DEFAULT"/>
        </intent-filter>
    </activity>
    <receiver android:name=".Receiver"
        android:enabled="true">
            <intent-filter>
                <action android:name="stas.test.intent.action.myreceiver"/>
            </intent-filter>
    </receiver>

</application>

First, you should (un)register receiver at onStart/onStop:

 @Override
    public void onStart() {
        super.onStart();

      registerReceiver(mBroadcastReceiver,                new IntentFilter("your name"));
    }

And then u can call Activity using PeddingIntent

 Intent intent = new Intent(context, MainActivity.class);
        PendingIntent pendingIntent = PendingIntent.getActivity(context, 0, intent, PendingIntent.FLAG_UPDATE_CURRENT);

PS, you can use Log instead of System.out.println.

It is better to register and unregister broadcast receiver on activity resume and pause.
@Override
    protected void onResume() {
        // TODO Auto-generated method stub
        super.onPause();
        this.registerReceiver(this.mReceiver);
    }
@Override
    protected void onPause() {
        // TODO Auto-generated method stub
        super.onPause();
        //unregister our receiver
        this.unregisterReceiver(this.mReceiver);
    }