onBackPressed causing problems in code

Question

I have following code in an activity SCORE:

@Override
    public void onBackPressed() {                  
        Intent i = new Intent(Score.this, MainActivity.class);
        startActivity(i);
    } 

Basically when user hits back i want them to go back to main activity. In main i have button when hit it exits the app something like this:

case R.id.exitButton:
            finish();
            break;

So when i start app and hit exit button it works fine it exits the app. But when i am at score page and hit back and than hit exit button app does not exit it goes back to score page. Can anyone please tell what am i doing wrong?

Answer 1

You starting the MainActivity from Score. Score is not being finished so the Score activity is still active and on the navigation stack.

try to do the following:

@Override
    public void onBackPressed() {                  
        Intent i = new Intent(Score.this, MainActivity.class);
        startActivity(i);
        finish();//Finishing the score activity is needed
    }

As stated in above comment it is not normal to have an exit button, but you are free to implement this if you want and or needed. For more information about the back stack have a look at the following android documentation.

http://developer.android.com/guide/components/tasks-and-back-stack.html

also there are various methods to to go back to an active activity have a look at Intent flags. Such as FLAG_ACTIVITY_CLEAR_TOP at the following documentation page:

http://developer.android.com/reference/android/content/Intent.html#FLAG_ACTIVITY_CLEAR_TOP

Answer 2

i think the problem is you use the finsh() method to finish the activity. may be you can use method like below:

case R.id.exitButton:
           System.exit(0);
            break;

hope that helps you.

Answer 3

For going to the main-activity after clicking back from score you want to add the following..

@Override
public void onBackPressed() {                  
     finish();
}

And for exit from that app after clicking exit button add the following.

case R.id.exit:
System.exit(0);
break;

Hope this helps you..