Android Intent to start Main activity of application

Question

I am trying to start the main activity from inside a BroadcastReceiver. I dont want to supply the activity class name but to use the action and category for android to figure out the main activity.

It doesnt seem to work.

Sending Code:

Intent startIntent = new Intent();

startIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startIntent.setAction(Intent.ACTION_MAIN);
startIntent.setPackage(context.getPackageName());
startIntent.addCategory(Intent.CATEGORY_LAUNCHER);        
context.startActivity(startIntent);

I get this error:

Caused bt: android.content.ActivityNotFoundException: No Activity found to handle Intent { act=android.intent.action.MAIN cat=[android.intent.category.LAUNCHER] flg=0x10000000 pkg=com.xyz.abc (has extras) }

Any ideas?

Why would you not want to specify the actual main activity by name? — Austyn Mahoney, Jun 14 '12 at 22:05

score 26 · Answer 1 · answered Sep 21 '15 at 12:37

26

Copy from another topic:

This works since API Level 3 (Android 1.5):

private void startMainActivity(Context context) throws NameNotFoundException {
    PackageManager pm = context.getPackageManager();
    Intent intent = pm.getLaunchIntentForPackage(context.getPackageName());
    context.startActivity(intent);
}

answered Sep 21 '15 at 12:37

TienLuong

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This is a much better answer than the approved one – FrankMonza Dec 13 '18 at 09:30

score 11 · Accepted Answer · answered Jun 14 '12 at 20:37

11

this is not the right way to startActivity.
try this code instead:

Intent startIntent = new Intent(context, MainActivity.class);
startIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);        
context.startActivity(startIntent);

answered Jun 14 '12 at 20:37

Tal Kanel

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I am having only the context of application instead of MainActivity.class in the library project. How can I start the application's main activity from the library project.? – Karthick Sep 17 '13 at 07:02
@Karthick: there is no problem using application context instead of MainActivity.class, but - if you won't use the Intent.FLAG_ACTIVITY_NEW_TASK flag, you'll get an exception in that case, because starting activity from application/Service context requires this flag. – Tal Kanel Sep 17 '13 at 07:16
If I am using context means, How can I use? Intent notificationIntent = new Intent(context, (Activity)(PushNotification.mActiveContext)); getting error. I need this in the below link scenario. http://stackoverflow.com/questions/18843118/launch-android-application-from-library-project – Karthick Sep 17 '13 at 07:20
@Karthick: I've seen your question, and if I understood currectly - I provided a good unswer – Tal Kanel Sep 17 '13 at 08:12
Intent startIntent = new Intent(getApplicationContext(), MainActivity.class); startIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK); getApplicationContext().startActivity(startIntent); – Alexandros Kourtis Jun 06 '22 at 08:29

Arnab Saha · Answer 3 · 2014-06-11T06:20:35.100

2

Even I had been trying to launch the MainActivity via a library Activity.

And this worked for me:

Intent startIntent = new Intent();
startIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startIntent.setPackage(getApplicationContext().getPackageName());
getApplicationContext().startActivity(startIntent);

Make sure you add the activity in your library's manifest!

edited Jun 11 '14 at 06:20

answered Jun 04 '14 at 06:17

Arnab Saha

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And here is exception when I tried the same: android.content.ActivityNotFoundException: No Activity found to handle Intent – TienLuong Sep 21 '15 at 12:33

score 1 · Answer 4 · answered Aug 20 '19 at 12:32

1

Even though it is too late. Might be useful for somone in the future. This helped me.

Intent intent = new Intent(this, MainActivity.class);
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
this.startActivity(intent);

answered Aug 20 '19 at 12:32

cantona_7

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Android Intent to start Main activity of application

4 Answers4

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