How to start activity in another application?

Question

I have application A defined as below:

<application android:icon="@drawable/icon" android:label="@string/app_name">     <activity android:name="com.example.MyExampleActivity"               android:label="@string/app_name">         <intent-filter>             <action android:name="android.intent.action.MAIN" />             <category android:name="android.intent.category.LAUNCHER" />         </intent-filter>     </activity> </application> 

Now in application B, how can I write the code to start the activity in application A? Thanks!

Answer 1

If both application have the same signature (meaning that both APPS are yours and signed with the same key), you can call your other app activity as follows:

Intent LaunchIntent = getActivity().getPackageManager().getLaunchIntentForPackage(CALC_PACKAGE_NAME); startActivity(LaunchIntent); 

Hope it helps.

Answer 2

If you guys are facing "Permission Denial: starting Intent..." error or if the app is getting crash without any reason during launching the app - Then use this single line code in Manifest

android:exported="true" 

Please be careful with finish(); , if you missed out it the app getting frozen. if its mentioned the app would be a smooth launcher.

finish(); 

The other solution only works for two activities that are in the same application. In my case, application B doesn't know class com.example.MyExampleActivity.class in the code, so compile will fail.

I searched on the web and found something like this below, and it works well.

Intent intent = new Intent(); intent.setComponent(new ComponentName("com.example", "com.example.MyExampleActivity")); startActivity(intent); 

You can also use the setClassName method:

Intent intent = new Intent(Intent.ACTION_MAIN); intent.setClassName("com.hotfoot.rapid.adani.wheeler.android", "com.hotfoot.rapid.adani.wheeler.android.view.activities.MainActivity"); startActivity(intent); finish(); 

You can also pass the values from one app to another app :

Intent launchIntent = getApplicationContext().getPackageManager().getLaunchIntentForPackage("com.hotfoot.rapid.adani.wheeler.android.LoginActivity"); if (launchIntent != null) {     launchIntent.putExtra("AppID", "MY-CHILD-APP1");     launchIntent.putExtra("UserID", "MY-APP");     launchIntent.putExtra("Password", "MY-PASSWORD");     startActivity(launchIntent);     finish(); } else {     Toast.makeText(getApplicationContext(), " launch Intent not available", Toast.LENGTH_SHORT).show(); }