how to avoid duplication screen in android

I ha开发者_如何转开发ve did a application in android by calling sub activities(B,C,D,E) from main activity(A),again calling that main Activity(A) from other sub Activities(B,C,D,E)by using

Intent in = new Intent();
in.setClass(getApplicationContext(), maindashbord.class);
in.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(in);

when i move back from main Activity to login page by clicking back button ,the main Activity displays again and again the times of I have called the subactivity. I have made all other activities in manifest.xml Android:noHistory="true"

but I need some static value in mainActivity for next login propose...

how can I replace the duplicate screen display?

thanks in advance..

After you call startActivity you can call finish() on the next line to stop the current activity.

To store a value even after the activity is, either use Shared Preferences or Extend the appliation class, which you can access from any activity using the getApplicationContext(). This will return a singleton, so the value will be the same in all activities.

try flag FLAG_ACTIVITY_NEW_TASK instead of FLAG_ACTIVITY_CLEAR_TOP.