Actionscript 3 在标签中，未显示模块中使用的值

我试图调用模块的一个函数（有两个参数）并为其赋值。 我可以在跟踪中看到分配的值，但在分配给标签时，相同的值不会显示

如果我直接将值指定给标签。它说：

错误：1009:空对象引用

如果对该标签使用

[Bindable]

元标记，则不会显示任何运行时错误，但也不会显示该值。我在互联网上搜索发现，

[Bindable]

元标记可以作为try-and-catch-blog使用

如何将值显示指定给标签

Main.mxml

 <?xml version="1.0" encoding="utf-8"?>
  <mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="absolute"   xmlns:custom="com.custom.*" xmlns:local="*" creationComplete="onload()">
  <mx:Script>
<![CDATA[
    import modules.AModule; 
    import mx.events.ModuleEvent;
    import mx.containers.VBox;
    import mx.containers.TitleWindow;
    import mx.controls.TextInput;
    import mx.controls.Button;
    import mx.containers.HBox;
    import mx.controls.Label;
    import mx.events.CloseEvent;
    import mx.controls.Text;
    import com.custom.CustomAlert;
    import mx.controls.Alert;
    import mx.containers.Canvas;
    import mx.events.ItemClickEvent;

    import mx.core.UIComponent;

    import mx.modules.ModuleManager;
    import mx.modules.IModuleInfo;
    import mx.containers.Box;
    import mx.controls.ProgressBar;

    //private var can:Canvas;

    public var titlewin:TitleWindow = new TitleWindow();
        public var usern:TextInput = new TextInput();
        public var passw:TextInput = new TextInput();
        public var vb:VBox = new VBox();
        public var hb1:HBox = new HBox();
        public var hb2:HBox = new HBox();
        public var hb3:HBox = new HBox();
        public var nc:NetConnection;

        public var bt1:Button = new Button();

        private var pb:ProgressBar;
    private var progressContainer:Box;
    private var info:IModuleInfo;
    private var module:UIComponent = null;
    public var can:Canvas= new Canvas();
    public function onload():void
    {
            var label1:Label= new Label();
        var label2:Label= new Label();
        label1.text="Username";
        label2.text="Password ";
        hb1.addChild(label1);
        hb1.addChild(usern);
        hb2.addChild(label2);
        hb2.addChild(passw);
        vb.addChild(hb1);
        vb.addChild(hb2);           
        bt1.label="Sign In";
        hb3.addChild(vb);
        hb3.addChild(bt1);
        titlewin.addChild(hb3);

        //Title Window creation starts here
        titlewin.title="Login";

        titlewin.setStyle("paddingLeft",20);
        titlewin.setStyle("paddingRight",20);
        titlewin.setStyle("paddingTop",20);
        titlewin.setStyle("paddingBottom",20);
        titlewin.setStyle("borderThicknessBottom",0);
        titlewin.setStyle("borderThicknessLeft",0);
        titlewin.setStyle("borderThicknessRight",0);
        titlewin.setStyle("borderThicknessTop",0);
        titlewin.setStyle("cornerRadius",0);
        titlewin.setStyle("borderColor","#D20101");
        this.addChild(titlewin);
        viewStack.enabled=false;
        ctbb.enabled=false;
        bt1.addEventListener(MouseEvent.CLICK, netconn);

    }

    private function onclick():void
    {
        if(usern.text!="")
        {
    this.removeChild(titlewin);
    viewStack.enabled=true; 
    ctbb.enabled=true;
    username.text=usern.text;
        }
        else
        {
            Alert.show("Please enter Username");
        }
    }


    private function netconn(event:MouseEvent):void
    {
        nc = new NetConnection();
        nc.connect("rtmp://localhost/loginhere",usern.text);
        nc.addEventListener(NetStatusEvent.NET_STATUS, onstatushandler);

    }

    private function onstatushandler(event:NetStatusEvent):void
    {
        if(event.info.code=="NetConnection.Connect.Success")
        {
            status.text="Connected";
        onclick();  
            }


        if(event.info.code=="NetConnection.Connect.Rejected")
        {
            status.text="Rejected";
        }
        if(event.info.code=="NetConnection.Connect.Failed")
        {
                status.text="Failed";
        }
    }



    private function JoinClick(event:MouseEvent):void{

        if(viewStack.numChildren==3)
        {
            Alert.show("You Cant Add More Button","Alert");

        }

        if(viewStack.numChildren<3)
        {

        if(viewStack.numChildren<2)
        {
        can.label="Button2";
        var button1:CustomButton= new CustomButton();
        button1.label="Leave Table";
        button1.x=300;
        button1.y=200;
        var txt:Text = new Text();
        txt.text=can.label;
        txt.x=50;
        txt.y=50;
        button1.addEventListener(MouseEvent.CLICK,remove2);
        can.addChild(button1);
        can.addChild(txt);
        loadmodule();
        }
        else
        {

        can.label="Button3";
        var button2:CustomButton= new CustomButton();
        button2.label="Leave Table";
        button2.x=300;
        button2.y=200;
        button2.addEventListener(MouseEvent.CLICK,remove3);
        can.addChild(button2);
        var txt1:Text = new Text();
        txt1.text=can.label;
        txt1.x=50;
        txt1.y=50;
        can.addChild(txt1);
        }
        can.setStyle("backgroundColor","0x5EA5BA");
        viewStack.addChild(can);
        if(viewStack.numChildren>2)
        {
            viewStack.selectedIndex=2;
        }
        else
        {
        viewStack.selectedIndex=1;
        }
        }

        }


        private function remove2(event:MouseEvent):void{
        Alert.show("Do you want to Leave    Table?","Confirmation",Alert.YES|Alert.NO,this,closeAlert2);
        }
        private function closeAlert2(event:CloseEvent):void{
        if(event.detail==Alert.YES)
        {
        viewStack.removeChildAt(1);
        }

        }
        private function remove3(event:MouseEvent):void{
        if(viewStack.numChildren>2)
        {
            Alert.show("Do You want to leave Table?","Confirmation",Alert.YES|Alert.NO,this,closeAlert3);

        }
        else
        {
            Alert.show("Do you want to Leave Table?","Confirmation",Alert.YES|Alert.NO,this,closeAlert1);

        }
        }

        private function closeAlert1(event:CloseEvent):void{
            if(event.detail==Alert.YES)
            {
                viewStack.removeChildAt(1);

            }
        }
        private function closeAlert3(event:CloseEvent):void{
            if(event.detail==Alert.YES)
            {
                    viewStack.removeChildAt(2);
            }
        }


            private function loadmodule():void
    {
            pb = new ProgressBar();
            pb.labelPlacement = "center";
            pb.label = "Loading %3 %";
            progressContainer = new Box();
            progressContainer.percentWidth = 100;
            progressContainer.percentHeight = 100;
            progressContainer.setStyle("horizontalAlign", "center");
            progressContainer.setStyle("verticalAlign", "middle");
            progressContainer.addChild(pb);  
            can.addChild(progressContainer);


        var moduleUrl:String="../bin-debug/modules/useModule.swf";
        info=ModuleManager.getModule(moduleUrl);
        if(info!=null)
        {
            info.addEventListener(ModuleEvent.READY, modEventHandler);
            info.addEventListener(ModuleEvent.ERROR,modErrorHandler);
            info.load();
        }
    }



    private function modEventHandler(e:ModuleEvent):void
    {
        info.removeEventListener(ModuleEvent.READY, modEventHandler);
        info.removeEventListener(ModuleEvent.ERROR, modErrorHandler);
        can.removeAllChildren();
        if(module==null)
        {

            module = info.factory.create() as UIComponent;
            if(module!=null)
            { 
                module.x=0;
                module.y=0;
                module.percentWidth=100;
                module.percentHeight=100;
                can.addChild(module);
                 if(module is AModule)
                {

                } 
            }
        }
        }

            private function modErrorHandler(event:ModuleEvent):void {


            //cleanup and display an error alert
            info.removeEventListener(ModuleEvent.READY, modEventHandler);
            info.removeEventListener(ModuleEvent.ERROR, modErrorHandler);
            info = null;
            Alert.show(event.toString(), "Error Loading Module");

          unloadModule();
        }   
                private function unloadModule():void 
                {
           can.removeAllChildren();
            if (module != null && info != null) {
                info.addEventListener(ModuleEvent.UNLOAD,    unloadEventHandler);
                info.unload();
            }
        }

                private function unloadEventHandler(e:ModuleEvent):void 
                {
            info.removeEventListener(ModuleEvent.UNLOAD, unloadEventHandler);
            module = null;
            info = null;
                 }


]]>
  </mx:Script>

 <mx:Canvas width="700" height="400" x="166" y="32">
 <mx:ViewStack id="viewStack"  width="100%" height="100%">
    <mx:Canvas label="Button1" backgroundColor="#5EA5BA" visible="true" id="can1" >
    <local:CustomButton label="Join" click="JoinClick(event)"  x="536" y="222"/>
    <mx:Label x="304" y="120" text="Label" id="username"/>
    <mx:Label x="304" y="55" text="Label" id="status"/>
    </mx:Canvas> 
</mx:ViewStack>

 </mx:Canvas>
  <custom:CustomControlBar x="166" y="423" id="ctbb">
  <custom:CustomToggleButtonBar  dataProvider="viewStack"/>
  </custom:CustomControlBar>

  </mx:Application>

---

我还没有看完整个代码，但我注意到一件事，您应该将值作为参数传递给子组件，并使用数据绑定动态更新参数

因此，在AModule.as中：

<mx:Module xmlns:mx="http://www.adobe.com/2006/mxml" layout="absolute" width="508"  height="218" implements="modules.AModule" backgroundColor="#F00F0F"  creationComplete="addlabel();">
<mx:Script>
    <![CDATA[
        import mx.core.Application;

        public var logsin:loginhere = new loginhere();

        [Bindable]
        public var username:String = "";
    ]]>
</mx:Script>

    <mx:TextInput id="txt3" text="{username}" x="30.5" y="10" width="79"/>
    <mx:Label id="lb1" text="{username}" x="31.5" y="40" width="78" text="Will it Change?"/>
</mx:Module> 

---

我遗漏的一点是，我无法在main.mxml中为接口创建一个实例 应在

modEventHandler

函数中创建var。在该函数中，应添加以下行

ichild=module as AModule;

ichild.addlabel(tt.text);

因此，将调用该模块，并在标签字段中显示该值

---

请让我知道，如果这是错误的工作方式。谢谢

请向我们展示您使用的代码-这将使我们更容易提供帮助。感谢您的回复。它太复杂了，无法显示为，因为代码从服务器获取数据并执行其余操作。你能帮我举个例子吗，因为我需要从主文件向模块中的函数（有两个参数）传递值并加载模块。Thankstory@JcFx，我已经更新了我的问题，如果你不理解我的问题，请告诉我。谢谢你+1这是一个好问题。我无法立即看到是什么导致了您的错误，但希望其他人能够提供帮助。Module.mxml中是否存在问题？我看到您在那里创建了一个新的Canvas1元素，而没有传递一个新字符串来设置它的标签。我遗漏的一点是，我无法创建一个变量，变量应该在

modEventHandler

函数中创建
在该函数中，下面的一行应该作为AModule添加

ichild=module；ichild.addlabel（tt.text）

因此调用模块，并在标签字段中显示值。请让我知道，如果这是错误的工作方式。

<mx:Module xmlns:mx="http://www.adobe.com/2006/mxml" layout="absolute" width="508"  height="218" implements="modules.AModule" backgroundColor="#F00F0F"  creationComplete="addlabel();">
<mx:Script>
    <![CDATA[
        import mx.core.Application;

        public var logsin:loginhere = new loginhere();

        [Bindable]
        public var username:String = "";
    ]]>
</mx:Script>

    <mx:TextInput id="txt3" text="{username}" x="30.5" y="10" width="79"/>
    <mx:Label id="lb1" text="{username}" x="31.5" y="40" width="78" text="Will it Change?"/>
</mx:Module> 

module.username = //var that holds username;

ichild=module as AModule;

ichild.addlabel(tt.text);