Start MAIN activity of the current application without knowing it's name

Question

I am trying to write an utility method, that would be able to start activity (belonging to current application) marked as "android.intent.action.MAIN". The utility method should not accept any parameters.

Desired code:

public void startMainActivity(Context context) {
    ...
}

Manifest:

<activity android:name=".MainActivity">
    <intent-filter>
        <action android:name="android.intent.action.MAIN" />
        <category android:name="android.intent.category.LAUNCHER" />
    </intent-filter>
</activity>

Any ideas?

Answer 1

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);
}

Answer 2

We used the nice solution of alex2k8 for a while until discovering it was not working on all devices on released version downloaded from Google Play.

Unfortunately the system didn't:

• throw any exception
• log the cause of the error

We used following workaround to solve it:

protected void startMainActivityWithWorkaround() throws NameNotFoundException, ActivityNotFoundException {
    final String packageName = getPackageName();
    final Intent launchIntent = getPackageManager().getLaunchIntentForPackage(packageName);
    if (launchIntent == null) {
      Log.e(LOG_TAG, "Launch intent is null");
    } else {
      final String mainActivity = launchIntent.getComponent().getClassName();
      Log.d(LOG_TAG, String.format("Open activity with package name %s / class name %s", packageName, mainActivity));
      final Intent intent = new Intent(Intent.ACTION_MAIN);
      intent.addCategory(Intent.CATEGORY_LAUNCHER);
      intent.setComponent(new ComponentName(packageName, mainActivity));
      // optional: intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
      startActivity(intent);
    }
}