Question

I’ve looked at the numerous posts on sending messages from services to activities, but I just can’t get this to work. My receiver is never being called. Does it matter if the Activity is not in the foreground?

Here is my scenario – I am running a web server as a service. When the web server receives a URL with link to a playlist, I need to send a message to my Activity that is acting as a media player. The media player will read the playlist and start playing the songs, videos, etc in order.

I don’t want the service to start new instances of the media player activity, as sometimes it may be sending commands like fast forward or pause.

From my web server service:

private void sendMessage() {


  Log.d("juice NonoHTTPD sender", "Sending message from Hub Web Server to Hub Player");

  Intent intent = new Intent();
  intent.putExtra(HubPlayer.ACTIVITY_PARAM_HOST, sAppHost);
  intent.putExtra(HubPlayer.ACTIVITY_PARAM_PORT, sAppPort);
  intent.putExtra(HubPlayer.ACTIVITY_PARAM_TYPE, sAppType);
  intent.putExtra(HubPlayer.ACTIVITY_PARAM_URL, sAppPath);    
  intent.setAction("com.jigawattlabs.hubplayer.play");
  appContext.sendBroadcast(intent);
}

From my activity:

public class HubPlayer extends Activity implements
OnBufferingUpdateListener, OnCompletionListener,
OnPreparedListener, OnVideoSizeChangedListener, SurfaceHolder.Callback 
{
private IntentFilter intentFilter = new IntentFilter("com.jigawattlabs.hubplayer.play");

MyBroadcastReceiver mReceiver = new MyBroadcastReceiver();

@Override
public void onCreate(Bundle bundle) {
    super.onCreate(bundle);

    setContentView(R.layout.mediaplayer_2);

    registerReceiver(mReceiver , intentFilter);

}

public class MyBroadcastReceiver extends BroadcastReceiver {

    @Override
    public void onReceive(Context context, Intent intent) {

        extras = intent.getExtras();

        sHost = extras.getString(ACTIVITY_PARAM_HOST);
        sPort = extras.getString(ACTIVITY_PARAM_PORT);
        sType = extras.getString(ACTIVITY_PARAM_TYPE);
        sXMLURL = extras.getString(ACTIVITY_PARAM_URL);

        DebugMsg("received broadcast in MyBroadcastReceiver.");
        processInputRequest();
    }
}
}

Even though it doesn’t seem necessary to put this in the manifest since I’m registering the BroadcastReceiver within my code, I also added an intent filter:

    <activity android:label="Media Hub Player" android:launchMode="singleTask"
        android:screenOrientation="unspecified"
        android:name=".HubPlayer" >
        <intent-filter>
            <action android:name="com.jigawattlabs.hubplayer.play" />
            <category android:name="android.intent.category.DEFAULT" />
        </intent-filter>            
    </activity> 

Thanks in advance.

Answer 1

OK, I have a workaround for this, but I was hoping for something better. Here is what I did

• If the service needs to send a message to an activity, it checks to see if the activity is running
• If the activity is running, it does the sendBroadcast as above
• If the activity is not running, I do a StartActivity and pass it the same info as I would with sendBroadcast
• From the activity, I pick up the intent either from the registered BroadcastReceiver or from the intent passed on onResume (if StartActivity is called).

Here is the code to check if an activity is running

public boolean isHubRunning() 
{ 
    boolean isServiceFound = false;

    ActivityManager activityManager = (ActivityManager)appContext.getSystemService (Context.ACTIVITY_SERVICE); 
    List<RunningTaskInfo> services = activityManager.getRunningTasks(Integer.MAX_VALUE); 
    isServiceFound = false; 
    for (int i = 0; i < services.size(); i++) 
    { 
        //DebugMsg(services.get(i).topActivity.toString());
        if (services.get(i).topActivity.toString().contains("juicemediahub.HubPlayer")) 
        {
            isServiceFound = true;
        }
    } 
    DebugMsg("Hub Player Running = " + String.valueOf(isServiceFound));
    return isServiceFound; 
}