How to Identify Multi Key down in keyboard event?
here is Example:-
private var activeKeys:Object=new Object();
stage.addEventListener(KeyboardEvent.KEY_DOWN, onKeyDownFunction);
stage.addEventListener(KeyboardEvent.KEY_UP, onKeyUpFunction);
private function onKeyDownFunction(event:KeyboardEvent):void
{
activeKeys[event.keyCode] = true;
}
private function onKeyUpFunction(event:KeyboardEvent): void
{
activeKeys[event.keyCode] = false;
}
now to easily find which key buttons are down in your Keyboard from activeKeys object.
this is the step for find key down:
activeKeys[Keyboard.LEFT] == true means left key arrow button is still key down.
activeKeys[Keyboard.LEFT]== false means left key arrow button is still key up.
and now How to move the ball with use multi key event?
private var speedX:Number = 0;
private var speedY:Number = 0;
private var fricrion:Number = 0.95;
private var power:Number = 5;
ball_mc.addEventListener(Event.ENTER_FRAME, onRunningFunction);
/** here ball_mc is a MovieClip **/
private function onRunningFunction(event:Event):void
{
if (activeKeyContainer[Keyboard.LEFT])
speedX = -power;
if (activeKeyContainer[Keyboard.RIGHT])
speedX = power;
if (activeKeyContainer[Keyboard.UP])
speedY = -power;
if (activeKeyContainer[Keyboard.DOWN])
speedY = power;
/** friction apply for reduce the speed slowly **/
speedX *= fricrion;
speedY *= fricrion;
/**--------------------------------------------**/
ball_mc.x += speedX;
ball_mc.y += speedY;
/** avoid ball out of stage **/
if (ball_mc.x < ball_mc.width/2)
ball_mc.x = ball_mc.width / 2;
if (ball_mc.x > stage.stageWidth - ball_mc.width / 2 )
ball_mc.x = stage.stageWidth-ball_mc.width/2;
if (ball_mc.y < ball_mc.height / 2 )
ball_mc.y = ball_mc.height/2;
if (ball_mc.y > stage.stageHeight - ball_mc.height / 2)
ball_mc.y = stage.stageHeight-ball_mc.height/2;
/**------------------------**/
}
simply try it your system friends.
...CHeeRS...
click above demo and press up,down,left,right key board event.
SourceFile
