如何同时完成（）两项活动？

Question

I am writing a math app for little kids to learn maths. It first prompts the user to select what kind of questions they want ( MainActivity ), and then it shows a bunch of questions ( QuestionsActivity ). After answering 10 questions, it tells you which question(s) did you answer correctly and which you didn't (ResultsActivity).

I know that Android puts all the activities on a stack. In my case, it would look like this:

ResultsActivity
QuestionsActivity
MainActivity

And when you call finish , an activity is popped from the stack. I want there to be a back to main menu button in the ResultsActivity to go back to the MainActivity . However, if I call finish in the ResultsActivity , the user would see QuestionsActivity ! So how am I going to call finish on the both activities?

Answer 1

Two options:

1. Call finish() in QuestionsActivity after you make the call to start the ResultsActivity. This will remove it from the stack so that pressing back from ResultsActivity returns to MainActivity.
2. Use Intent.FLAG_ACTIVITY_CLEAR_TOP in the intent to go back to MainActivity. This will clear all activities that are on top of it.

Answer 2

You can clear your stack by simple starting your MainActivity again and clearing the stack with the following flags:

  final Intent intent = new Intent(context, MainActivity.class);
  intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK | Intent.FLAG_ACTIVITY_NEW_TASK);
  startActivity(intent);