java - Exit the app when back button in device is clicked

Question

There are 3 activities in my app.

Activity A(Main Page) -> Activity B -> Activity C.

When submit button in Activity C is clicked, it will back to Activity A again. When I click the back button in device to exit the app, it will back to Activity C again, then B and A , then only can exit.

Is there a way to let the app straight away exit when back button in device is pressed in Activity A?

I add below code in Activity A, but the problem is it still goes to Activity C instead of exit.

boolean doubleBackToExitPressedOnce = false;

@Override
public void onBackPressed() {
    if (doubleBackToExitPressedOnce) {
        super.onBackPressed();
        return;
    }

    this.doubleBackToExitPressedOnce = true;
    Toast.makeText(this, "Please click BACK again to exit", Toast.LENGTH_SHORT).show();

    new Handler().postDelayed(new Runnable() {

        @Override
        public void run() {
            doubleBackToExitPressedOnce=false;                       
        }
    }, 2000);
} 

Answer 1

Probably when you submit on activity C instead of closing it, you're opening activity A again. So do the following: start activity C for result from activity B, when you submit on activity C call setResult() and then call finish() on activity C then override onActivityResult() in activity B and when you get the result from activity C call finish () on activity B. Then you're back to activity A and if you press back, your APP will close. :) Hope this helps