External actionscript file

Question

Hi, I've more than two components accessing the same
function. Hence, I would like the function to be on an external
actionscript file.
My codes are as followed:
<?xml version="1.0" encoding="utf-8"?>
<mx:HDividedBox xmlns:mx="
http://www.adobe.com/2006/mxml"
width="100%" height="100%">
<mx:Metadata>
[Event(name="scaleChange",
type="actionscripts.sliderChange")]
</mx:Metadata>
<mx:Script>
<![CDATA[
import actionscripts.sliderChange;
import mx.managers.DragManager;
import mx.core.DragSource;
import mx.events.DragEvent;
import flash.events.MouseEvent;
import mx.containers.Box;
[Bindable]
[Embed(source="/images/map.jpg")]
public var map:Class;
public var oWidth:Number = 2800; //original map width - 1200
public var oHeight:Number = 2100; //original map height -
900
public var xOff:Number;
public var yOff:Number;
private function dragMap(event:Event):void{
event.currentTarget.addEventListener(MouseEvent.MOUSE_DOWN,
mouseMoveHandler);
private function doDragEnter(event:DragEvent):void{
DragManager.acceptDragDrop(Box(event.target));
private function mouseMoveHandler(event:MouseEvent):void{
event.currentTarget.useHandCursor=true;
var dragInitiator:Image=Image(event.currentTarget);
var ds:DragSource = new DragSource();
ds.addData(event.currentTarget, 'img');
var imageProxy:Image = new Image();
imageProxy.source = map;
xOff = event.currentTarget.mouseX;
yOff = event.currentTarget.mouseY;
DragManager.doDrag(dragInitiator, ds, event, imageProxy, 0,
0, 0.00);
private function doDragDrop(event:DragEvent):void{
targetMap.x = event.currentTarget.mouseX - xOff;
targetMap.y = event.currentTarget.mouseY - yOff;
public function onSliderChange():void{
var temp:Number = 100-scale.value;
targetMap.width = temp/100*oWidth+1200;
targetMap.height = temp/100*oHeight+900;
map.smoothing = true;
var nWidth:Number = targetMap.width;
var nHeight:Number = targetMap.height;
var sliderObj:sliderChange = new sliderChange(nWidth as
Number,nHeight as Number,"scaleChange");
dispatchEvent(sliderObj);
]]>
</mx:Script>
<mx:Canvas id="scaling" width="75%" height="100%">
<mx:VBox width="100%" height="100%"
horizontalAlign="center" verticalAlign="middle">
<mx:Box id="mapContainer" width="500" height="500"
horizontalAlign="center" verticalAlign="middle"
horizontalScrollPolicy="off" verticalScrollPolicy="off"
dragEnter="doDragEnter(event);" dragDrop="doDragDrop(event);">
<mx:Image source="{map}" id="targetMap"
scaleContent="true" creationComplete="dragMap(event);" />
</mx:Box>
<mx:HSlider id="scale" liveDragging="true" minimum="1"
maximum="100" labels="['1','100']" width="500" height="30"
change="onSliderChange()" />
<mx:Text text="{scale.value.toFixed(2)} km" />
</mx:VBox>
</mx:Canvas>
<mx:Canvas width="25%" height="100%"
styleName="sideBar">
<mx:Label text="test test" />
</mx:Canvas>
</mx:HDividedBox>
How do I make the drag and drop functions in the
<mx:Script></mx:Script> to be in an external
actionscript file so that this component can access it for the drag
and drop to work?
Any help is very much appreciated. ^^

Answer 1

You can reference a external actionscript file in a
<mx:Script source="myScripts.as"/>
I do not use it this way as it is not a vary OO way to do
things.
I will generally create a singleton class (so it is only
instantiated once)
and use it for utility type functions.
For example:
public class UtilityClass
private static var _instance:UtilityClass;
public function UtilityClass()
public static function getInstance():UtilityClass
if(_instance == null)
_instance = new UtilityClass();
return _instance;
public function myFunction():void
Then in a mxml
<mx:list id="list"
dragDrop="UtilityClass.getInstance().myfunction()"