android messagebox

Question

I need to display a msgbox in the onFinish method of mu main activty. But I get the following exception :

android.view.WindowManager$BadTokenException: Unable to add window -- token android.os.BinderProxy@43202998 is not valid; is your activity running?

No, my activity is not running, I'm in the onFinish treatment, but I doesn't have any other context...