trigger an event in another activity
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is there a way trigger an event in another activity which might be below the current activity in the stack (the activity below the current activity is not a part of my application)

for eg: if activity 'Act1' of application 'A' launches Activity 'Act12' of appliication 'AB', then is there a way for 'Act12' to trigger an event (like a `backButtonPressed()` or `onPause()` etc) for 'Act1' ? Thanks in Advance.