as3调用外部swf里的类的方法

　　as3项目要调用外部swf里的类有3种方法：

　　1.将外部的swf发布为swc，使用时将swc引用添加到相应的项目中，这应该是最简单的一种引用。不过当项目中的类或组件比较多时就会使项目发布生成的swf文件大小过大;

　　2.通过资源绑定外部的，然后直接通过类名获取。如：[Embed(source="assets/icon/skin.swf",symbol="Btn_Max")],这种方法也会引起swf文件过大;

　　3.通过域来来获取外部swf里的绑定类，这种方法可以在需要用时才去加载相应的swf文件然后再获取所需要的类。

　　下面是根据第三种方法来获取所需要的类：

　　

package com.mobiano.flipbook.pageeditor
{
    import com.flasht.tui.display.TArrow;
    import com.mobiano.flipbook.config.FlipBookConfig;
    import com.tflash.Components.util.SWFLoader;
    
    import flash.display.DisplayObject;
    import flash.errors.IOError;
    import flash.events.Event;
    import flash.events.IOErrorEvent;
    import flash.events.ProgressEvent;
    import flash.utils.Dictionary;

    public class PlugInManager
    {
        public static var allExternalClass:Object={};
        //public var loadingQueue:Object={};
        //public var swfLoader:SWFLoader;
        public var loadingQueue:Dictionary=new Dictionary();
        private static var canInstace:Boolean=false;
        private static var instace:PlugInManager;
        
        private var filePrefix:String="./files/pageConfig/";
        private var fileSuffix:String=".swf";
        public function PlugInManager()
        {
            if(!canInstace){
                throw new Error("Can't new PlugInManager"); 
            }
        }
        
        public static function getInstace():PlugInManager{
            if(instace==null){
                canInstace=true;
                instace=new PlugInManager();
                canInstace=false;
            }
            
            return instace;
        } 
        
        public function getComponent(target:TAnnoPlugIn,cpName:String,extClassName:String):void{
            if(cpName==null||cpName.length<1||extClassName==null||extClassName.length<1)return ;
            if(allExternalClass.hasOwnProperty()){
                //return allExternalClass[cpName];
                var swfLoader:SWFLoader=allExternalClass[cpName];
                var cl:Class=swfLoader.GetClass(extClassName);
                if(cl!=null){
                    var extObj:IPlugInInterface=createSWFClass(cl);
                    if(extObj!=null){
                        target.extObj=extObj;
                    }
                }
            }else{
                load(target,cpName,extClassName);
            }
            //return null;
        }
        
        public function getSwfUrl(cpName):String{
            if(cpName!=null){
                return filePrefix+cpName+fileSuffix;
            }
            return null;
        }
        
        protected function getURLFrom(url:String):String{
            return com.mobiano.flipbook.config.FlipBookConfig.getURLForm(url);
        }
        
        private function load(target:TAnnoPlugIn,cpName:String,extClName:String):void{
            var swfUrl:String=getSwfUrl(cpName);
            if(swfUrl==null||swfUrl.length<1)return;
            swfUrl=getURLFrom(swfUrl);
            
            var swfLoader:SWFLoader=new SWFLoader(swfUrl);
            swfLoader.addEventListener(Event.COMPLETE,onComplete);
            swfLoader.addEventListener(ProgressEvent.PROGRESS,onProgress);
            swfLoader.addEventListener(IOErrorEvent.IO_ERROR,onIOError);
            var obj:Object={target:target,compontName:cpName,extClassName:extClName};
            
            //loadingQueue[cpName]=obj;
            loadingQueue[swfLoader]=obj;
            swfLoader.Load();
            
        }
        
        private function onComplete(evt:Event):void{
            trace(evt.currentTarget);
             if(evt.currentTarget is SWFLoader){
                 var loader:SWFLoader=evt.currentTarget as SWFLoader;
                if(loader in loadingQueue){
                    var obj:Object=loadingQueue[loader];
                    if(obj["target"]&&obj["compontName"]&&obj["extClassName"]){
                        var cpName:String=obj["compontName"];
                        var extClassName:String=obj["extClassName"];
                        
                        allExternalClass[cpName]=loader;
                        
                        var cl:Class=loader.GetClass(extClassName);
                        var target:TAnnoPlugIn=obj["target"];
                        if(cl!=null){
                            //allExternalClass[cpName]=cl;
                            var extObj:IPlugInInterface=createSWFClass(cl);
                            if(extObj!=null){
                                target.extObj=extObj;
                            }
                        }
                    }
                    //loader.GetClass(
                    //var target:TAnnoPlugIn=loadingQueue[loader];
                } 
             }
        }
        
        private function createSWFClass(cl:Class):IPlugInInterface{
            var extObj:IPlugInInterface;
            try{
                if(cl!=null){
                    extObj=new cl();
                }
                
            }catch(e:Error){
                return null;
            }
            return extObj;
        }
        
        private function onProgress(evt:ProgressEvent):void{
            
        }
        
        private function onIOError(evt:IOError):void{
            throw new Error("Load swf error:"+evt);
        }
    
    }
}

package com.tflash.Components.util
{
    import flash.display.DisplayObject;
    import flash.display.Loader;
    import flash.display.LoaderInfo;
    import flash.events.Event;
    import flash.events.EventDispatcher;
    import flash.events.IEventDispatcher;
    import flash.events.IOErrorEvent;
    import flash.events.ProgressEvent;
    import flash.net.URLRequest;
    import flash.system.ApplicationDomain;
    import flash.system.LoaderContext;
    
    [Event(name="complete", type="flash.events.Event")]
    [Event(name="progress",type="flash.events.ProgressEvent")]
    [Event(name="io_error",type="flash.events.IOErrorEvent")]
    
    public class SWFLoader extends EventDispatcher
    {
        private var loader:Loader;
        private var content:DisplayObject;
        private var loadComplete:Boolean=false;
        private var url:String;
        public function SWFLoader(url:String)
        {
            this.url=url;
        
        }
        
        public function Load(url:String=null):void{
            if(url!=null){
                this.url=url;
            }
            loadComplete=false;
            if(loader==null){
                loader=new Loader();
            }else{
                loader.unloadAndStop(true);
                if(loader.contentLoaderInfo.hasEventListener(Event.COMPLETE)){
                    loader.contentLoaderInfo.removeEventListener(Event.COMPLETE,onLoadComplete);
                }
                if(loader.contentLoaderInfo.hasEventListener(ProgressEvent.PROGRESS)){
                    loader.contentLoaderInfo.removeEventListener(IOErrorEvent.IO_ERROR,onLoadIOError);
                }
                if(loader.contentLoaderInfo.hasEventListener(IOErrorEvent.IO_ERROR)){
                    loader.contentLoaderInfo.removeEventListener(IOErrorEvent.IO_ERROR,onLoadIOError)
                }
            }
            
            var context:LoaderContext=new LoaderContext();
            context.applicationDomain=new ApplicationDomain(ApplicationDomain.currentDomain);
            var request:URLRequest=new URLRequest(this.url);
            loader.contentLoaderInfo.addEventListener(Event.COMPLETE,onLoadComplete);
            loader.contentLoaderInfo.addEventListener(ProgressEvent.PROGRESS,onLoadProgress);
            loader.contentLoaderInfo.addEventListener(IOErrorEvent.IO_ERROR,onLoadIOError);
            loader.load(request,context);
        }
        
    
        private function onLoadProgress(evt:ProgressEvent):void{
            
            this.dispatchEvent(evt);
        }
        
        private function onLoadComplete(evt:Event):void{
            evt.currentTarget.removeEventListener(Event.COMPLETE,onLoadComplete);
            evt.currentTarget.removeEventListener(IOErrorEvent.IO_ERROR,onLoadIOError);
            evt.currentTarget.removeEventListener(IOErrorEvent.IO_ERROR,onLoadIOError);
            content=(evt.currentTarget as LoaderInfo).content;
            loadComplete=true;
            this.dispatchEvent(new Event(Event.COMPLETE));
        
        }
        
        private function onLoadIOError(evt:IOErrorEvent):void{
            evt.currentTarget.removeEventListener(Event.COMPLETE,onLoadComplete);
            evt.currentTarget.removeEventListener(IOErrorEvent.IO_ERROR,onLoadIOError);
            evt.currentTarget.removeEventListener(IOErrorEvent.IO_ERROR,onLoadIOError);
            
            this.dispatchEvent(evt);
        }
        
        
        /**
         * 获取当前ApplicationDomain内的类定义
         *
         * name类名称，必须包含完整的命名空间,如 Grave.Function.SWFLoader
         * info加载swf的LoadInfo，不指定则从当前域获取
         * return获取的类定义，如果不存在返回null
         */
        public function GetClass(name:String):Class{

            if(loadComplete&&loader!=null){
                if(loader.contentLoaderInfo.applicationDomain.hasDefinition(name)){
                    return loader.contentLoaderInfo.applicationDomain.getDefinition(name) as Class;
                }else{
                    return null;
                }
            }
            return null;
        }
        
        public function GetContent():DisplayObject{
            return content;
        }
        
        public function GetLoader():Loader{
            
            return loader;
        }
        
    }
}