android - Clear all activities in a task?

Question

I have a splash screen activity, then a login activity. My history stack looks like:

SplashActivity
LoginActivity

when the user successfully logs in via LoginActivity, I want to start WelcomeActivity, but clear the entire stack:

SplashActivity
LoginActivity // launches WelcomeActivity ->
WelcomeActivity

// but now all three are in the history stack, while I only
// want WelcomeActivity in the stack at this point.

Is there some flag I can use to do that?

// LoginActivity.java
Intent intent = new Intent(this, WelcomeActivity.class);
intent.addFlag(Intent.FLAG_ACTIVITY_CLEAR_TASK);
startActivity(intent);
finish();

Not sure if using the FLAG_ACTIVITY_CLEAR_TASK will clear out all activities in my task or not. I can do this 'manually' by unwinding the stack by using startActivityForResult() calls, but will be more fragile and more code to maintain.

Thanks

Answer 1

Yes that should work fine. You could use:

• FLAG_ACTIVITY_CLEAR_TOP
• FLAG_ACTIVITY_SINGLE_TOP
• FLAG_ACTIVITY_CLEAR_TASK
• FLAG_ACTIVITY_NEW_TASK

which ensures that if an instance is already running and is not top then anything on top of it will be cleared and it will be used, instead of starting a new instance (this useful once you've gone Welcome activity -> Activity A and then you want to get back to Welcome from A, but the extra flags shouldn't affect your case above).