How do I make 2 KeyDown functions work independently? - actionscript-3

Question

package
{
import flash.display.MovieClip;
import flash.events.*;
public class untitledCode extends MovieClip
{
private var speed:Number = 5;
public function untitledCode()
{
stage.addEventListener(KeyboardEvent.KEY_DOWN, whenKey1);
stage.addEventListener(KeyboardEvent.KEY_DOWN, whenKey2);
}
private function whenKey1(event:KeyboardEvent):void
{
if (event.keyCode == 38)
{
mcPlayer1.y -= speed;
}
if (event.keyCode == 40)
{
mcPlayer1.y += speed;
}
if (event.keyCode == 37)
{
mcPlayer1.x -= speed;
}
if (event.keyCode == 39)
{
mcPlayer1.x += speed;
}
if (event.keyCode == 96)
{
mcPlayer1.play();
}
}
private function whenKey2(event:KeyboardEvent):void
{
if (event.keyCode == 87)
{
mcPlayer2.y -= speed;
}
if (event.keyCode == 83)
{
mcPlayer2.y += speed;
}
if (event.keyCode == 65)
{
mcPlayer2.x -= speed;
}
if (event.keyCode == 68)
{
mcPlayer2.x += speed;
}
if (event.keyCode == 90)
{
mcPlayer2.play();
}
}
}
}
There are 2 MovieClips, mcPlayer1 and mcPlayer2. When I hold a key for one MovieClip and then press a key for another, the first MovieClip stops(and vice versa). How do I make them move simultaneously.

Answer 1

Based on the other answer I informed you about that was already on SO, I tested their answer and although it works, there is keyboard lag with their implementation. So I optimized it using the ENTER_FRAME event...
package
{
import flash.display.MovieClip;
import flash.events.Event;
import flash.events.KeyboardEvent;
import flash.ui.Keyboard;
public class Main extends MovieClip
{
private var speed:Number = 5;
private var _keyDownStatus:Object = { };
public function Main()
{
stage.addEventListener(KeyboardEvent.KEY_DOWN, onDown);
stage.addEventListener(KeyboardEvent.KEY_UP, onUp);
stage.addEventListener(Event.ENTER_FRAME, keyCheck);
}
private function onUp(e:KeyboardEvent):void {
_keyDownStatus[e.keyCode] = false;
}
private function onDown(e:KeyboardEvent):void {
_keyDownStatus[e.keyCode] = true;
}
private function keyCheck(e:Event):void {
// Player 1 Events
if (_keyDownStatus[Keyboard.LEFT]) {
mcPlayer1.x -= speed;
}
if (_keyDownStatus[Keyboard.RIGHT]) {
mcPlayer1.x += speed;
}
if (_keyDownStatus[Keyboard.UP]) {
mcPlayer1.y -= speed;
}
if (_keyDownStatus[Keyboard.DOWN]) {
mcPlayer1.y += speed;
}
if (_keyDownStatus[Keyboard.NUMPAD_0]) {
mcPlayer1.play();
}
//Player 2 Events
if (_keyDownStatus[Keyboard.A]) {
mcPlayer2.x -= speed;
}
if (_keyDownStatus[Keyboard.D]) {
mcPlayer2.x += speed;
}
if (_keyDownStatus[Keyboard.W]) {
mcPlayer2.y -= speed;
}
if (_keyDownStatus[Keyboard.S]) {
mcPlayer2.y += speed;
}
if (_keyDownStatus[Keyboard.Z]) {
mcPlayer2.play();
}
}
}
}
I've tested this in Flash CC 2014 and it works perfectly! I did change the name of the class in my example for my example to work, so please change it to be whatever class name you need it to be.

Answer 2

I do recommend you do add only one key down event listener and save each pushed key and add a key up event listener to remove, so, you can control when only one key is pressed or multiple keys.
I created a simple example (just to explain the main logic), you should adapt and optimize it for your own needs.
private var keyControl:Vector.<uint>;
public function Test()
{
keyControl = new Vector.<uint>();
stage.addEventListener(KeyboardEvent.KEY_DOWN, onDownHandler, false, 0, true);
stage.addEventListener(KeyboardEvent.KEY_UP, onUpHandler, false, 0, true);
}
private function onUpHandler(event:KeyboardEvent):void
{
keyControl.splice(keyControl.indexOf(event.keyCode), 1);
}
private function onDownHandler(event:KeyboardEvent):void
{
if(!isKeyPressed(event.keyCode)) keyControl.push(event.keyCode);
/*
to check if some key is being pressed use
if(isKeyPressed(Keyboard.SPACE))
{
// do something
}
if(isKeyPressed(Keyboard.SPACE) && isKeyPressed(Keyboard.A))
{
// do something
}
*/
}
private function isKeyPressed(key:uint):Boolean
{
var returnValue:Boolean;
for (var i:int = 0, numKeys:uint = keyControl.length; i < numKeys; i++)
{
if(keyControl[i] == key)
{
returnValue = true;
break;
}
}
return returnValue;
}