How to launch the app instead of building notification when receiving GCM message?

Question

I've just implemented a GCM application that shows notification when GCM message arrives. how can launch the application when message arrives? same as viber. you get a pop up box when message arrives.

EDIT:

thanks a lot for helps but I guess what most of you guys have explained require the user to click on the notification in order to launch the application. I need to have the activity automatically launched as soon as the GCM message arrives regardless of what app is in the foreground or even when the application is in background or killstate.

here is my GCMIntentService code:

package com.google.android.gcm.demo.app;

import com.google.android.gms.gcm.GoogleCloudMessaging;

import android.app.IntentService;
import android.app.NotificationManager;
import android.app.PendingIntent;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.os.SystemClock;
import android.support.v4.app.NotificationCompat;
import android.util.Log;
import android.widget.Toast;


public class GCMIntentService extends IntentService {
    public static final int NOTIFICATION_ID = 1;
    private NotificationManager mNotificationManager;
    NotificationCompat.Builder builder;

    public GCMIntentService() {
        super("GcmIntentService");
    }
    public static final String TAG = "GCM Demo";

    @Override
    protected void onHandleIntent(Intent intent) {
        Bundle extras = intent.getExtras();
        GoogleCloudMessaging gcm = GoogleCloudMessaging.getInstance(this);
        // The getMessageType() intent parameter must be the intent you received
        // in your BroadcastReceiver.
        String messageType = gcm.getMessageType(intent);

        if (!extras.isEmpty()) {  // has effect of unparcelling Bundle
            /*
             * Filter messages based on message type. Since it is likely that GCM will be
             * extended in the future with new message types, just ignore any message types you're
             * not interested in, or that you don't recognize.
             */
            if (GoogleCloudMessaging.MESSAGE_TYPE_SEND_ERROR.equals(messageType)) {
                sendNotification("Send error: " + extras.toString());
            } else if (GoogleCloudMessaging.MESSAGE_TYPE_DELETED.equals(messageType)) {
                sendNotification("Deleted messages on server: " + extras.toString());
                // If it's a regular GCM message, do some work.
            } else if (GoogleCloudMessaging.MESSAGE_TYPE_MESSAGE.equals(messageType)) {
                // This loop represents the service doing some work.
                for (int i = 0; i < 5; i++) {
                    Log.i(TAG, "Working... " + (i + 1)
                            + "/5 @ " + SystemClock.elapsedRealtime());
                    try {
                        Thread.sleep(5000);
                    } catch (InterruptedException e) {
                    }
                }
                Log.i(TAG, "Completed work @ " + SystemClock.elapsedRealtime());
                startActivity(new Intent(getBaseContext(), DemoActivity.class).setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP));
                Intent myIntent = new Intent(getBaseContext(), DemoActivity.class);
                startActivity(myIntent);
                // Post notification of received message.
                //sendNotification("Received: " + extras.toString());
                Log.i(TAG, "Received: " + extras.toString());
                Toast.makeText(getApplicationContext(), extras.toString(), Toast.LENGTH_LONG).show();
            }
        }
        // Release the wake lock provided by the WakefulBroadcastReceiver.
        GcmBroadcastReceiver.completeWakefulIntent(intent);
    }

    // Put the message into a notification and post it.
    // This is just one simple example of what you might choose to do with
    // a GCM message.

    private void sendNotification(String msg) {
        mNotificationManager = (NotificationManager)
                this.getSystemService(Context.NOTIFICATION_SERVICE);

        PendingIntent contentIntent = PendingIntent.getActivity(this, 0,
                new Intent(this, DemoActivity.class), 0);

        NotificationCompat.Builder mBuilder =
                new NotificationCompat.Builder(this)
                        .setSmallIcon(R.drawable.ic_stat_gcm)
                        .setContentTitle("GCM Notification")
                        .setStyle(new NotificationCompat.BigTextStyle()
                                .bigText(msg))
                        .setContentText(msg);
           Toast.makeText(getApplicationContext(),msg,Toast.LENGTH_LONG).show();

        mBuilder.setContentIntent(contentIntent);
        mNotificationManager.notify(NOTIFICATION_ID, mBuilder.build());
    }
}

Answer 1

You can do it with PendingIntent

PendingIntent contentIntent = PendingIntent.getActivity(this, 0, new Intent(this, DemoActivity.class), 0);

NotificationCompat.Builder mBuilder = new NotificationCompat.Builder(this)
    .setSmallIcon(R.drawable.ic_stat_gcm)
    .setContentTitle("GCM Notification")
    .setStyle(new NotificationCompat.BigTextStyle()
    .bigText(msg))
    .setContentText(msg);

mBuilder.setContentIntent(contentIntent);
mNotificationManager.notify(NOTIFICATION_ID, mBuilder.build());

as in documentation

If you want, you can make your DemoActivity dialog-like or something else.

Answer 2

Usual way to do this thing is via PendingIntent add it to your Notification.Builder or Notification for example:

PendingIntent intent = PendingIntent.getActivity(context, 0, new Intent(context, HomeActivity.class), 0);
notificationBuilder.setContentIntent(pendingIntent);

To add pop-out box you may see helpfull this answer

Edit:

Just saw your comment in order to launch activity just call startActivity(); in your GcmIntentService when appropriate notification arrived.

Answer 3

Add this in GcmIntentService class

@Override
        protected void onHandleIntent(Intent intent) {
            Bundle extras = intent.getExtras();
            GoogleCloudMessaging gcm = GoogleCloudMessaging.getInstance(this);
            // The getMessageType() intent parameter must be the intent you received
            // in your BroadcastReceiver.
            String messageType = gcm.getMessageType(intent);

            if (!extras.isEmpty()) {  // has effect of unparcelling Bundle
                if (GoogleCloudMessaging.
                        MESSAGE_TYPE_SEND_ERROR.equals(messageType)) {
                    sendNotification("Send error: " + extras.toString());
                } else if (GoogleCloudMessaging.
                        MESSAGE_TYPE_DELETED.equals(messageType)) {
                    sendNotification("Deleted messages on server: " +
                            extras.toString());

                } else if (GoogleCloudMessaging.
                        MESSAGE_TYPE_MESSAGE.equals(messageType)) {
                    ** //Start your activity here .This will automatically launch your activity**
                }
            }

Answer 4

You use the package name / class directly, for example to create a new intent to call the twidroid program you'd use the followinglink text:

Intent intent = new Intent("com.twidroid.SendTweet");

You'd probably want to put a try/catch around for a ActivityNotFoundException for when the application is not installed.