Apache flex 从Flex 4的ViewStack中删除子内容

在下面的示例中，当我单击“添加内容”时，新的堆栈内容将按预期加载到ViewStack中。但当我单击“Close Content”时，我希望它关闭ViewStack中新创建的内容并切换到“defaultContent”内容

谁能告诉我哪里出了问题吗？提前谢谢

// TestProject.mxml (application)
<?xml version="1.0" encoding="utf-8"?>
<s:WindowedApplication xmlns:fx="http://ns.adobe.com/mxml/2009" 
                       xmlns:s="library://ns.adobe.com/flex/spark" 
                       xmlns:mx="library://ns.adobe.com/flex/mx">
    <s:layout>
        <s:VerticalLayout/>
    </s:layout>
    <fx:Script>
        <![CDATA[
            import com.NewContent;

            private function addContent():void
            {
                var content:NewContent = new NewContent();
                var navContent:NavigatorContent = new NavigatorContent();
                navContent.id = 'newContent';
                navContent.label = 'newContent';
                navContent.width = Number('100%');
                navContent.height = Number('100%');
                navContent.addElement(content);

                viewStack.addElement(navContent);
                viewStack.selectedChild = navContent;
            }
        ]]>
    </fx:Script>
    <mx:ViewStack id="viewStack" width="100%" height="100%">
        <s:NavigatorContent id="defaultContent"
                            label="defaultContent">
            <s:Button click="addContent()" label="Add Content"/>
        </s:NavigatorContent>
    </mx:ViewStack>
</s:WindowedApplication>

// NewContent.mxml (component)
<?xml version="1.0" encoding="utf-8"?>
<s:Group xmlns:fx="http://ns.adobe.com/mxml/2009" 
         xmlns:s="library://ns.adobe.com/flex/spark" 
         xmlns:mx="library://ns.adobe.com/flex/mx"
         width="100%" height="100%">
    <fx:Script>
        <![CDATA[
            import mx.core.FlexGlobals;
            private function closeContent():void
            {
                FlexGlobals.topLevelApplication.viewStack.removeChild('newContent');
                FlexGlobals.topLevelApplication.viewStack.selectedChild = 'defaultContent';
            }
        ]]>
    </fx:Script>
    <s:Button click="closeContent()" label="Close Content"/>
</s:Group>

//TestProject.mxml（应用程序）
//NewContent.mxml（组件）

selectedChild

期望的是子对象本身，而不是标签

相反，请尝试以下方法：

public function removeContent():void
{
     Viewstack(this.parent).selectedIndex = 0;
     this.parent.removeChild(this);
}

注意-通常建议避免使用FlexGlobals.topLevelApplication，因为它会导致一个非常紧密耦合且脆弱的应用程序。

// TestProject.mxml (application)
private function addContent():void
{
    var content:NewContent = new NewContent();
    content.addEventListener("removeMe",onRemove,false,0,true);
    var navContent:NavigatorContent = new NavigatorContent();
    navContent.id = 'newContent';
    navContent.label = 'newContent';
    navContent.width = Number('100%');
    navContent.height = Number('100%');
    navContent.addElement(content);

    viewStack.addElement(navContent);
    viewStack.selectedChild = navContent;

private function onRemove(event:Event):void
{
    var content:NewContent = event.currentTarget as NewContent;
    content.removeEventListener("removeMe",onRemove,false);
    viewStack.removeChild(content.parent.parent.parent);
}

// NewContent.mxml (component)
public function removeContent():void
{
    dispatchEvent(new Event("removeMe"));
}

---

谢谢，但是我现在收到以下错误：“TypeError:error#1034:类型强制失败：无法转换spark.components:：Group@8614c29到mx.containers.ViewStack”。有什么想法吗？