Hide android activity

Question

I'm developing a phone call's app in react native using react-native-fcm to notify the user when theres incoming calls. This is how I the app upon the receive of a notification.

    Intent launchIntent = getPackageManager().getLaunchIntentForPackage("com.myApp");

    startActivity(launchIntent);

Everything fine till now , but I want my activity to start on the background and not show any visual information about it. I can do this in MainActivity with moveTaskToBack(true); but it flickers by 1 second, any way to do this without flickering ?

Are you using https://github.com/evollu/react-native-fcm – Dayan Jun 20 '17 at 18:44 — Dayan, Jun 20 '17 at 18:44
Yes Im using , react-native-fcm. – Nicholas Mendes Jun 21 '17 at 08:55 — Nicholas Mendes, Jun 21 '17 at 08:55

score 0 · Answer 1 · answered Jun 20 '17 at 16:37

0

Why are you using an Activity? If you want to run in the background, use a Service. If that later needs to show a UI, then you launch an Activity.

answered Jun 20 '17 at 16:37

Gabe Sechan

90,003
9
87
127

You can do anything in a Service you can in an Activity, except show a UI (and even that can be worked around). – Gabe Sechan Jun 20 '17 at 16:43

score 0 · Answer 2 · edited Jun 20 '20 at 09:12

Since you just want to show notifications from a firebase service. Look at your manifest file:

<service android:name=".YourFirebaseMessagingService" android:enabled="true" android:exported="true">
  <intent-filter>
     <action android:name="com.google.firebase.MESSAGING_EVENT"/>
  </intent-filter>
</service>

The service has an intent filter with the com.google.firebase.MESSAGING_EVENT action, you then just need to implement the service by extending FirebaseMessagingService and overwrite the onMessageReceived method.

Note that onMessageReceived is provided for most message types, with the following exceptions:

Notification messages delivered when your app is in the background. In this case, the notification is delivered to the device’s system tray. A user tap on a notification opens the app launcher by default.

Messages with both notification and data payload, both background and foreground. In this case, the notification is delivered to the device’s system tray, and the data payload is delivered in the extras of the intent of your launcher Activity.

Services run on the main thread unless explicitly told otherwise. This means you can show any notification you'll like, or start a new Activity.

Here's an example of the above:

public class YourFirebaseMessagingService extends FirebaseMessagingService {

    @Override
    public void onMessageReceived(RemoteMessage remoteMessage) {
        if (remoteMessage.getNotification().getBody() != null) {
            Log.e("FIREBASE", "Message Notification Body: " + remoteMessage.getNotification().getBody());
            //DO WHATEVER YOU NEED HERE TO DISPLAY YOUR MESSAGE OR ACTIVITY
        }
    }
}

Note that if you wish to wake up your background application, you will need to perform a POST to the following URL:

POST https://fcm.googleapis.com/fcm/send

And the following headers:

Key: Content-Type, Value: application/json

Key: Authorization, Value: key=<your-server-key>

For more information on this, check out this link and this answer.

the only problem is that event that trigger my application to open is in a npm package react-native-fcm how can I handle this is android files ? — Nicholas Mendes, Jun 20 '17 at 17:41
@NicholasMendes Do you have a firebase service in the manifest? Like so `` — Dayan, Jun 20 '17 at 18:07

Hide android activity

2 Answers2