Android: Clear Activity Stack -

this question has answer here:

• on logout, clear activity history stack, preventing “back” button opening logged-in-only activites 17 answers

i want o clear activities after clicking on logout button. used following code. please tell me correct way implement it.

public class logoutlistner implements onclicklistener {      private activity mactivity;      public logoutlistner(activity a) {         this.mactivity = a;     }      @override     public void onclick(view arg0) {         intent intent = new intent(mactivity, loginactivity.class);         intent.setflags(intent.flag_activity_clear_top | intent.flag_activity_no_history);         mactivity.startactivity(intent);     } 

intent intent = new intent(mactivity, loginactivity.class); intent.addflags(intent.flag_activity_clear_top); intent.addflags(intent.flag_activity_new_task); mactivity.startactivity(intent);