Ball Movement With Multi Keyboard Event in ActionScript3.0

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