How to send parameters from a notification-click to an activity?

Take a look at this guide (creating a notification) and to samples ApiDemos "StatusBarNotifications" and "NotificationDisplay".

For managing if the activity is already running you have two ways:

1. Add FLAG_ACTIVITY_SINGLE_TOP flag to the Intent when launching the activity, and then in the activity class implement onNewIntent(Intent intent) event handler, that way you can access the new intent that was called for the activity (which is not the same as just calling getIntent(), this will always return the first Intent that launched your activity.

2. Same as number one, but instead of adding a flag to the Intent you must add "singleTop" in your activity AndroidManifest.xml.

If you use intent extras, remeber to call PendingIntent.getActivity() with the flag PendingIntent.FLAG_UPDATE_CURRENT, otherwise the same extras will be reused for every notification.

Encounter same issue here. I resolve it by using different request code, use same id as notification, while creating PendingIntent. but still don't know why this should be done.

PendingIntent contentIntent = PendingIntent.getActivity(context, **id**, notificationIntent, 0);
notif.contentIntent = contentIntent;
nm.notify(**id**, notif);

After reading some email-lists and other forums i found that the trick seems to add som unique data to the intent.

like this:

   Intent notificationIntent = new Intent(Main.this, Main.class);
   notificationIntent.putExtra("sport_id", "sport"+id);
   notificationIntent.putExtra("game_url", "gameURL"+id);

   notificationIntent.setData((Uri.parse("foobar://"+SystemClock.elapsedRealtime()))); 

I dont understand why this needs to be done, It got something to do with the intent cant be identified only by its extras...

In your notification implementation, use a code like this:

NotificationCompat.Builder nBuilder = new NotificationCompat.Builder(this, NOTIFICATION_CHANNEL_ID);
...
Intent intent = new Intent(this, ExampleActivity.class);
intent.putExtra("EXTRA_KEY", "value");

PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, intent, PendingIntent.FLAG_UPDATE_CURRENT);
nBuilder.setContentIntent(pendingIntent);
...

To Get Intent extra values in the ExampleActivity, use the following code:

...
Intent intent = getIntent();
if(intent!=null) {
    String extraKey = intent.getStringExtra("EXTRA_KEY");
}
...

VERY IMPORTANT NOTE: the Intent::putExtra() method is an Overloaded one. To get the extra key, you need to use Intent::get[Type]Extra() method.

Note: NOTIFICATION_ID and NOTIFICATION_CHANNEL_ID are an constants declared in ExampleActivity

Please use as PendingIntent while showing notification than it will be resolved.

PendingIntent intent = PendingIntent.getActivity(this, 0, notificationIntent, PendingIntent.FLAG_UPDATE_CURRENT);

Add PendingIntent.FLAG_UPDATE_CURRENT as last field.

G'day, I too can say that I tried everything mentioned in these posts and a few more from elsewhere. The #1 problem for me was that the new Intent always had a null bundle. My issue was in focusing too much on the details of "have I included .this or .that". My solution was in taking a step back from the detail and looking at the overall structure of the notification. When I did that I managed to place the key parts of the code in the correct sequence. So, if you're having similar issues check for:

1. Intent notificationIntent = new Intent(MainActivity.this, NotificationActivity.class);

2a. Bundle bundle = new Bundle();

//I like specifying the data type much better. eg bundle.putInt

2b. notificationIntent.putExtras(bundle);
3. PendingIntent contentIntent = PendingIntent.getActivity(MainActivity.this, WIZARD_NOTIFICATION_ID, notificationIntent,
                    PendingIntent.FLAG_UPDATE_CURRENT);
notificationIntent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP | Intent.FLAG_ACTIVITY_SINGLE_TOP);
4. NotificationManagerCompat notificationManager = NotificationManagerCompat.from(this);
5.          NotificationCompat.Builder nBuilder =
                    new NotificationCompat.Builder(this)
                            .setSmallIcon(R.drawable.ic_notify)
                            .setContentTitle(title)
                            .setContentText(content)
                            .setContentIntent(contentIntent)
                            .setDefaults(Notification.DEFAULT_SOUND | Notification.DEFAULT_VIBRATE)
                            .setAutoCancel(false)//false is standard. true == automatically removes the notification when the user taps it.
                            .setColor(getResources().getColor(R.color.colorPrimary))
                            .setCategory(Notification.CATEGORY_REMINDER)
                            .setPriority(Notification.PRIORITY_HIGH)
                            .setVisibility(NotificationCompat.VISIBILITY_PUBLIC);
            notificationManager.notify(WIZARD_NOTIFICATION_ID, nBuilder.build());

With this sequence I get a valid bundle.

If you use

android:taskAffinity="myApp.widget.notify.activity"
android:excludeFromRecents="true"

in your AndroidManifest.xml file for the Activity to launch, you have to use the following in your intent:

Intent notificationClick = new Intent(context, NotifyActivity.class);
    Bundle bdl = new Bundle();
    bdl.putSerializable(NotifyActivity.Bundle_myItem, myItem);
    notificationClick.putExtras(bdl);
    notificationClick.setData(Uri.parse(notificationClick.toUri(Intent.URI_INTENT_SCHEME) + myItem.getId()));
    notificationClick.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK | Intent.FLAG_ACTIVITY_NEW_TASK);  // schließt tasks der app und startet einen seperaten neuen

    TaskStackBuilder stackBuilder = TaskStackBuilder.create(context);
    stackBuilder.addParentStack(NotifyActivity.class);
    stackBuilder.addNextIntent(notificationClick);

    PendingIntent notificationPendingIntent = stackBuilder.getPendingIntent(0, PendingIntent.FLAG_UPDATE_CURRENT);
    mBuilder.setContentIntent(notificationPendingIntent);

Important is to set unique data e.g. using an unique id like:

notificationClick.setData(Uri.parse(notificationClick.toUri(Intent.URI_INTENT_SCHEME) + myItem.getId()));