# ActionScript

To use this language, use the class "language-actionscript".

## Comments

    // Single line comment
    /* Multi-line
    comment */

## Literal values

    17
    "hello"
    -3
    9.4
    null
    true
    false

## Classes

    class A {}
    class B extends A {}

## Inline XML

    var employees:XML =
        <employees>
            <employee ssn="123-123-1234">
                <name first="John" last="Doe"/>
                <address>
                    <city>San Francisco</city>
                    <state>CA</state>
                    <zip>98765</zip>
                </address>
            </employee>
            <employee ssn="789-789-7890">
                <name first="Mary" last="Roe"/>
                <address>
                    <city>Newton</city>
                    <state>MA</state>
                    <zip>01234</zip>
                </address>
            </employee>
        </employees>;

## Full example

    package {
      import flash.display.*;
      import flash.events.*;
      import flash.filters.BlurFilter;
      import flash.geom.*;
      import flash.ui.*;
      public class ch23ex2 extends Sprite {
        protected const BMP_SCALE:Number = 1/2;
        protected const D:Number = 1.015;
        protected const DIM_EFFECT:ColorTransform = new ColorTransform(D, D, D);
        protected const B:int = 16;
        protected const BLUR_EFFECT:BlurFilter = new BlurFilter(B, B, 1);
        protected var RLUT:Array, GLUT:Array, BLUT:Array;
        protected var sourceBmp:BitmapData;
        protected var colorBmp:BitmapData;
        protected var touches:Array = new Array();
        protected var fingerShape:Shape = new Shape();
        public function ch23ex2() {
          try {
            var test:Class = Multitouch;
            if (Multitouch.supportsTouchEvents) {
              Multitouch.inputMode = MultitouchInputMode.TOUCH_POINT;
              init();
            } else {
              trace("Sorry, this example requires multitouch.");
            }
          } catch (error:ReferenceError) {
            trace("Sorry, but multitouch is not supported in this runtime.");
          }
        }
        protected function init():void {
          //create a black-and-white bitmap and a color bitmap, only show the color
          sourceBmp = new BitmapData(
            stage.stageWidth*BMP_SCALE, stage.stageHeight*BMP_SCALE, false, 0);
          colorBmp = sourceBmp.clone();
          var bitmap:Bitmap = new Bitmap(colorBmp, PixelSnapping.ALWAYS, true);
          bitmap.width = stage.stageWidth; bitmap.height = stage.stageHeight;
          addChild(bitmap);

          //create finger shape to paste onto the bitmap under your touches
          fingerShape.graphics.beginFill(0xffffff, 0.1);
          fingerShape.graphics.drawEllipse(-15, -20, 30, 40);
          fingerShape.graphics.endFill();

          //create the palette map from a gradient
          var gradient:Shape = new Shape();
          var m:Matrix = new Matrix();
          m.createGradientBox(256, 10);
          gradient.graphics.beginGradientFill(GradientType.LINEAR,
            [0x313ad8, 0x2dce4a, 0xdae234, 0x7a1c1c, 0x0f0303],
            [1, 1, 1, 1, 1], [0, 0.4*256, 0.75*256, 0.9*256, 255], m);
          gradient.graphics.drawRect(0, 0, 256, 10);
          var gradientBmp:BitmapData = new BitmapData(256, 10, false, 0);
          gradientBmp.draw(gradient);
          RLUT = new Array(); GLUT = new Array(); BLUT = new Array();
          for (var i:int = 0; i < 256; i++) {
            var pixelColor:uint = gradientBmp.getPixel(i, 0);
            //I drew the gradient backwards, so sue me
            RLUT[256-i] = pixelColor & 0xff0000;
            GLUT[256-i] = pixelColor & 0x00ff00;
            BLUT[256-i] = pixelColor & 0x0000ff;
          }

          stage.addEventListener(TouchEvent.TOUCH_BEGIN, assignTouch);
          stage.addEventListener(TouchEvent.TOUCH_MOVE, assignTouch);
          stage.addEventListener(TouchEvent.TOUCH_END, removeTouch);
          stage.addEventListener(Event.ENTER_FRAME, onEnterFrame);
        }
        protected function assignTouch(event:TouchEvent):void {
          touches[event.touchPointID] = event;
        }
        protected function removeTouch(event:TouchEvent):void {
          delete touches[event.touchPointID];
        }
        protected function onEnterFrame(event:Event):void {
          for (var key:String in touches) {
            var touch:TouchEvent = touches[key] as TouchEvent;
            if (touch) {
              //plaster the finger image under your finger
              var m:Matrix = new Matrix();
              m.translate(touch.stageX*BMP_SCALE, touch.stageY*BMP_SCALE);
              sourceBmp.draw(fingerShape, m, null, BlendMode.ADD);
            }
          }
          var O:Point = new Point(0, 0);
          //blur and ever-so-slightly brighten the image to make the color last
          sourceBmp.applyFilter(sourceBmp, sourceBmp.rect, O, BLUR_EFFECT);
          sourceBmp.colorTransform(sourceBmp.rect, DIM_EFFECT);
          //we've calculated the image in grayscale brightnesses, now make it color
          colorBmp.paletteMap(sourceBmp, sourceBmp.rect, O, RLUT, GLUT, BLUT, null);
        }
      }
    }