how to bring to front task the already started this activity on the back stack
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How to bring to front the task that already started  activity (this activity can be on the stack back) if anther task wants to start this activity.
I tried to do this with intent and flags but it isn't helping. the new task starts root activity and not brings  to front the task that already started this  activity.

 tasks created not from the same application

hope you can help.If can give some code
