错误 #1069：找不到属性并且没有默认值

Question

我在 Flash Builder 中处理的项目存在问题。 以下是我的堆栈和代码示例。有人可以告诉我我做错了什么吗？

感谢您的宝贵时间。

-- 堆栈--

ReferenceError：错误 #1069：在 WOAPPv2 上找不到属性 page4，并且没有默认值。 在 WOAPPv2/dragDropHandler()[/Users/martinw/Documents/Adobe Flash Builder 4/WOAPPv2/src/WOAPPv2.mxml:165] 在 flash.events::EventDispatcher/dispatchEventFunction() 在 flash.events::EventDispatcher/dispatchEvent() 在 mx.core::UIComponent/dispatchEvent()[E:\dev\4.x\frameworks\projects\framework\src\mx\core\UIComponent.as:12528] 在 mx.managers.dragClasses::DragProxy/_dispatchDragEvent()[E:\dev\4.x\frameworks\projects\framework\src\mx\managers\dragClasses\DragProxy.as:374] 在 mx.managers.dragClasses::DragProxy/mouseUpHandler()[E:\dev\4.x\frameworks\projects\framework\src\mx\managers\dragClasses\DragProxy.as:599]

--代码示例--这是可行的

import mx.core.DragSource;
import mx.events.DragEvent;
import mx.managers.DragManager;

        private function initiateDrag(event:MouseEvent,value:String):void{

            var dragInitiator:Image= event.currentTarget as Image;   

            var dragSource:DragSource = new DragSource();
            dragSource.addData(value, 'value');
            DragManager.doDrag(dragInitiator, dragSource, event);
        } 

        private function dragEnterHandler(event:DragEvent):void {
            var dropTarget:VBox =event.currentTarget as VBox;
            if (event.dragSource.hasFormat('value')) {
                DragManager.acceptDragDrop(dropTarget);
            }
        }

private function dragDropHandler(event:DragEvent):void {
            var pageName:String = event.currentTarget.name as String;
            var value:String = event.dragSource.dataForFormat('value') as String;
            this[pageName].source = "assets/big/"+value; 


        }

<s>

<s:HGroup id="hGr"
              requestedColumnCount="2"
              variableColumnWidth="false"
              columnWidth="475"
              height="450"
              gap="100"
              clipAndEnableScrolling="true" paddingLeft="10" paddingRight="10">


        <mx:VBox name="page1"
                 backgroundColor="#EFEFF0"
                 verticalScrollPolicy="off" 
                 horizontalScrollPolicy="off"
                 horizontalAlign="center" verticalAlign="middle"
                 dragEnter="dragEnterHandler(event)"
                 dragDrop="dragDropHandler(event)"
                 width="475"
                 x="0">


            <mx:Image id="page1" showBusyCursor="true" width="713" height="692" scaleContent="true" maintainAspectRatio="true" minWidth="713" minHeight="692" scaleX="1" scaleY="1" horizontalAlign="center" verticalAlign="top"/>
        </mx:VBox>


    </s:HGroup>

如果我通过在运行时创建容器和图像来这样做，它会中断

<script>


   private function initVars():void {
            createSpreads();
        }


        public function createSpreads():void {

            var s:VBox = new VBox();
            s.name ="page4";

            s.setStyle("backgroundColor","#fe0000"); 
            s.verticalScrollPolicy="off";
            s.horizontalScrollPolicy="off";
            s.setStyle("horizontalAlign","center");
            s.setStyle("verticalAlign","middle");
            s.addEventListener(DragEvent.DRAG_ENTER, dragEnterHandler);
            s.addEventListener(DragEvent.DRAG_DROP, dragDropHandler);
            s.width= 475;
            s.setStyle("x","0");
            hGr.addElement(s);

            hGrCol4.text = "Vboxname: "+s.name+"VboxID: "+s.id;

            var page3:Image = new Image();
            page3.id ="page4";

            page3.showBusyCursor = true;
            page3.width = 713;
            page3.height = 692
            page3.scaleContent = true;
            page3.maintainAspectRatio = true;
            page3.minWidth = 713;
            page3.minHeight = 692;
            page3.scaleX = 1;
            page3.scaleY = 1;
            page3.source = "assets/big/IMG_7112.jpg";
            page3.setStyle("backgroundColor","#ffffff");
            page3.setStyle("horizontalAlign","center");
            page3.setStyle("verticalAlign","top");
            s.addElement(page3);

            hGrCol3.text = "Imagename: "+page3.name+"ImageID: "+page3.id;
        }


import mx.core.DragSource;
import mx.events.DragEvent;
import mx.managers.DragManager;

        private function initiateDrag(event:MouseEvent,value:String):void{

            var dragInitiator:Image= event.currentTarget as Image;   

            var dragSource:DragSource = new DragSource();
            dragSource.addData(value, 'value');
            DragManager.doDrag(dragInitiator, dragSource, event);
        } 

        private function dragEnterHandler(event:DragEvent):void {
            var dropTarget:VBox =event.currentTarget as VBox;
            if (event.dragSource.hasFormat('value')) {
                DragManager.acceptDragDrop(dropTarget);
            }
        }

private function dragDropHandler(event:DragEvent):void {
            var pageName:String = event.currentTarget.name as String;
            var value:String = event.dragSource.dataForFormat('value') as String;
            this[pageName].source = "assets/big/"+value; 

        }


</script>

<s>

<s:HGroup id="hGr"
              requestedColumnCount="2"
              variableColumnWidth="false"
              columnWidth="475"
              height="450"
              gap="100"
              clipAndEnableScrolling="true" paddingLeft="10" paddingRight="10">

    </s:HGroup>

</s>

上面没有 HGroup 中的容器返回'在 WOAPPv2 上找不到属性 page4 并且没有默认值' - 我的最终结果应该是这个

page4.source = "assets/big/imagename.jpg";

我被难住了。我重新考虑它，可能只是创建 vbox，然后设置触发器来创建图像并填充到 samedragDropHandler 中。 想法？

以下是解决方案 - 再次感谢 alxx。现在我需要开始在这里向其他人贡献我的知识。

public function dragDropHandler(event:DragEvent):void {

        // Retrieve the Image Name from Drop
        var value:String = event.dragSource.dataForFormat('value') as String;

                    //
        event.currentTarget.getChildAt(0).source = "assets/big/"+value;

        }

Answer 1

...继续此处进行正确格式化
问题线：

var value:String = event.dragSource.dataForFormat('value') as String;
this[pageName].source = "assets/big/"+value;

我的目标是添加元素一个 vbox 和 与共享名称的图像孩子 一个 id 并使用事件来获取 当前目标名称是图像 控制

不确定我是否理解正确。如果 event.currentTarget 是您需要的 Image，您可以将其转换为 Image。或者您需要在某处找到另一个图像（在中继器中生成的图像）​​？

更新

“我正在尝试使用 VBox 的名称作为字符串，用于点表示法来引用其中的图像”

DisplayObjects 的名称只是标签，而不是参考。如果您认为您可以使用 JS DOM 中的名称遍历对象层次结构，那么不，它在 Flash 中以其他方式完成。您可以使用event.currentTarget 获得对VBox 的reference - 它的名称（字符串）更有用。您可以使用 getChildAt 获取其中的 Image。