actionscript 3 - Action Script 3. How to hide button till game ends? -

i'm creating game , need make when game on "try again" button appears. have done button don't know how hide till game ends. shown time.

this button:

function tryagain(e:mouseevent):void {     trace("try again");     createcards(); }

button.visible = false; function tryagain(e:mouseevent):void {     button.visible = true;     createcards(); }

Abdulmateen