Question

I try to do preloder in Flex for my project written in Flash.
I make this with the help of this site
link text
My Flash project have next source in main class called Game

stage.addEventListener(KeyboardEvent.KEY_DOWN, keyDown);
stage.addEventListener(KeyboardEvent.KEY_UP, keyUp);

private function keyDown(event:KeyboardEvent) {
   if (event.keyCode == 81 && q_was_push == false) q_was_push = true;
   if (event.keyCode == 81) press_q = true;
   if (event.keyCode == 65) press_a = true;
   if (event.keyCode == 83) press_s = true;
   if (event.keyCode == 32) press_space = true;
} ...

When I take new swf file maked by Flex, I have error
TypeError: Error #1009: Cannot access a property or method of a null object reference.
at Game()

if I comment

//stage.addEventListener(KeyboardEvent.KEY_DOWN, keyDown);
//stage.addEventListener(KeyboardEvent.KEY_UP, keyUp);

Flex application work but Flash application does not react to button presses

Please how I can make preloader and work buttons together

Answer 1

The stage property will be null until a display object is added to the display list. Listen to the addedToStage event and add the key listeners from there.

addEventListener(Event.ADDED_TO_STAGE, onAddedToStage);
function onAddedToStage(e:Event):void
{
    stage.addEventListener(KeyboardEvent.KEY_DOWN, keyDown);
    stage.addEventListener(KeyboardEvent.KEY_UP, keyUp);
}