How to clear specific activity from the stack history?

Question

Suppose I have an application containing activities named A,B,C,D. Now, consider A has been launched as the root activity and B has been launched from A and C has been launched from B and D has been launched from C. Now I have a button named "Remove" in the activity D. If suppose, I press the button "Remove" in the activity D, then the activity B and activity C should be removed from the history stack. On Pressing back key from the activity D should display activiy A instead of C. I don't know how to implement this. Can anyone help me to resolve this problem?

Answer 1

I'm not sure you can directly programmatically remove activities from the history, but if you use startActivityForResult() instead of startActivity(), then depending on the return value from your activity, you can then immediately finish() the predecessor activity to simulate the behaviour you want. By using this method in all your activities, you can have this behaviour cascading the activity stack to allow you to go from activity D to activity A.

I know this isn't your situation, but in future if you know before you start the activity that you don't want the predecessor to remain, you can call finish() immediately after startActivity().

Please see the section called "Lifetime of the New Screen" in Common Tasks and How to do Them in Android

Answer 2

I agree with @RivieraKid, but I think of another way: When you press "Remove" you set a custom flag to true.

Override the back key event:

public void onBackPressed() {   if (!remove){     super.onBackPressed();   }else{     Intent goToA = new Intent((this,ActivityA.class););     goToA.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);     startActivity(goToA);   } } 

Do you think this does what you want?

Good luck.