Clear draw popup overlay from mapview in android?

In my screen i have two button one is two show map and second one two show list . I am populating an popup on android map using onTap method of "ItemizedOverlay" class,开发者_运维知识库 and now if I press on second button to show list , popup message shows as it is, it not cancelled.

pls let me know how can I dismiss this popup message dialog.