Urgent! simple Help needed

I’m trying to do a simple text box, below is the code:

private function onKey(event:KeyboardEvent):void
{
    trace("Key Pressed: " + String.fromCharCode(event.charCode) + " (character code: " + event.charCode + ")"); 
}

however, I dunno why It cannot receive alphabet input, everytime i press on the keyboard’s alphabet, my mouse keep change to the flash’s short cut key…

how to disable it so that i can trace my alphabet input properly?