it solved. Thanks mr.kglad.
i just change the ADDED (message 1 code) to ADDED_TO_STAGE (message 3 code) and remain the fullScreenTakeOver =false;
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import flash.system.fscommand;
fscommand("fullscreen", "true");
fscommand("allowscale", "false");
stage.addEventListener(Event.ADDED_TO_STAGE,FLVAdded, true);
function FLVAdded(e:Event):void
{
if (e.target is FLVPlayback)
{
e.target.fullScreenTakeOver = false;
}
}
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