应用IMXMLObject自定义功能性组件

在flex项目中，应用到非显示的功能性组件，一种方法是直接定义actionScript类。另外一种方法是实现IMXMLObject接口。实现IMXMLObject接口的好处，是可以直接调用功能函数。

IMXMLObject中的方法function initialized(document:Object, id:String):void,在IMXMLObject置入MXML时被直接调用，类似于触发了initialized事件。如以下示例：

TempCom.as

package component {

    import flash.display.Shape;
    import mx.core.IMXMLObject;
    
    public class TempCom implements IMXMLObject{
        public var id:String="tempCom";
        public var rect:Shape;
        
        public var paramOne:String="paramOne";
        public var paramTwo:String="paramTwo";
      
        public function executSome(para1:String,para2:String):void{
            trace("para1:->"+para1,"para2:->"+para2,"from executSome");
        }
        public function initialized(document:Object, id:String):void
        {
            rect=createShape();
            executSome(paramOne,paramTwo);
        }
        private function createShape():Shape{
            var rect:Shape=new Shape;
            rect.graphics.beginFill(0xffccff);
            rect.graphics.drawRect(0,0,100,100);
            rect.graphics.endFill();
            return rect;
        }
    }
}

MainApp.mxml

<?xml version="1.0" encoding="utf-8"?>

<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009" 

               xmlns:s="library://ns.adobe.com/flex/spark" 

               xmlns:mx="library://ns.adobe.com/flex/mx" 

               xmlns:com="component.*"

               xmlns:mxmlCom="mxmlCom.*"

               minWidth="955" minHeight="600"

               creationComplete="application1_creationCompleteHandler(event)">

    <fx:Script>

        <![CDATA[

            import mx.events.FlexEvent;

            protected function application1_creationCompleteHandler(event:FlexEvent):void

            {

                container.addChild(tempCom.rect);

            }

            

        ]]>

    </fx:Script>

    <fx:Declarations>

        <com:TempCom  id="tempCom" paramOne="aaa" paramTwo="bbbb"/>

    </fx:Declarations>

    <mx:UIComponent id="container"/>

</s:Application>  

运行结果会显示出一个正方形，并输出：" para1:->aaa para2:->bbbb from executSome ".