Android stop backward navigation
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I'm implementing a game for android platform. The game is nearly ready, but I got a weird problem:

When a player completes game, a "congratulations, you win" page is displayed. A button from that view is redirecting to main page.
The problem arises when player clicks back button, because game is displayed again. 

Is there a way to control what back button behavior should appear? like redirect to main page always 

Thank you in advance

Vyrphan