android activity only happens once but i need it to repeat

so my app has two tabs

tab 1 is a login page then

tab 2 is a user details

the user needs to loginfrom tab 1 then only details would load from tab 2 so if the user didn't login and goes to tab 2, an alertdialog would show the problem is, after going back to tab 1 and if the user does not login aga开发者_开发百科in prior to tab 2, the alertdialog would not show again. I'm not sure if I should use onRestart or onPause or something..

SOLVED!

the easiest way to do is to set the flag in the tabhost .addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);

thanks for the help guys :D

Change Your Application Flow.

make one tab represents a set of activity.

make use of activity group.