check keyboard state without using KeyboardEvent in AS3
Is it possible to check for pressed keys without using the KeyboardEvent?
I have an ENTER_FRAME event setup called enterFrameHandler and I want to check within the function enterFrameHandler if any keys are pressed.
normally when using a KeyboardEvent I could check for keys easily using a switch that checks the KeyCode of the event, but in an ENTER_FRAME event this isn't possible for me.
Is there any other way of checking the keyboard's state within the ENTER_FRAME event?
UPDATE: I found this AS2 script:
onClipEvent (enterFrame) {
if (Key.isDown(Key.LEFT)) {
_x -= power;
}
if (Key.isDown(Key.RIGHT)) {
_x += power;
}
if (Key.isDown(Key.UP)) {
_y -=power;
}
i开发者_高级运维f (Key.isDown(Key.DOWN)) {
_y +=power;
}
}
This seems to be doing what I want, but it's in AS2, does anyone know how to 'translate' this into AS3?
Store key states in a dictionary or object:
stage.addEventListener(KeyboardEvent.KEY_UP, keyHandleUp);
stage.addEventListener(KeyboardEvent.KEY_DOWN, keyHandleDown);
private var hash:Object = {};
private function keyHandleUp(event:KeyboardEvent):void {
delete hash[event.keyCode];
}
private function keyHandleDown(event:KeyboardEvent):void {
hash[event.keyCode] = 1;
}
private function isKeyDown(code:int):Boolean {
return hash[code] !== undefined;
}
The short answer is no Why don't you want to use a KeyboardEvent event listener?
With a KeyboardEvent.KEY_DOWN
listener added to the stage, keeping the key pressed works just fine, so there's no need for the ENTER_FRAME.
private function keyDownHandler(evt:KeyboardEvent):void
{
switch(evt.keyCode)
{
case 37: //left key
trace("Move left");
break;
case 38: //up key
trace("Move up");
break;
case 39: //right key
trace("Move right");
break;
case 40: //down key
trace("Move down");
break;
}
}
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