Question

如何引用在运行时添加的子元素？

示例代码：

for(var i:Number=1; i<=5;i++){
    var mygroup:HGroup = new HGroup();

    var mybutton:Button = new Button();
    mybutton.label = "Browse Directory";
    mybutton.addEventListener(MouseEvent.CLICK,browsedirectory);

    var dirlbl:Label = new Label();
    dirlbl.text = "C:/some directory/";
    dirlbl.id = "path"+i;

    mygroup.addElement(mybutton);
    mygroup.addElement(dirlbl);
    mygroup.id = "group"+i;
    mainGroup.addElement(mygroup);
}

public function updatepath():void
{
    this["path1"].text = "new path";
}

当我尝试通过调用this["path1"].text = "new path";来更改标签中的目录路径时，它会遇到错误

Error #1069: Property path1 not found and there is no default value.

如何引用这些子元素？

谢谢。

Answer 1

Caution, code not tested!

您可以先检查特定容器中的所有元素（据您所知）：

private function displayChildren(element):void {
    for (var i = 0; i < element.numChildren; i++){
        var child = element.getChildAt(i);

        if (child != null) {
            trace ('position: '+i+' child name:' + child.name);

            for (var j = 0; j < child.numChildren; j++){
                displayChildren(child.getChildAt(j));
            }
        }
    }
} 

displayChildren(mainGroup);

这应输出如下内容：

trace= position: 0 child name : "group1";     <- HGroup 
trace= position: 0 child name : undefined;    <- Button without id
trace= position: 1 child name : "path1";      <- Label
...

因此，您应该能够以下列方式访问标签：

mainGroup["group1"]["path1"].text = "new path text";

--------------------更新-------------------------- -

如果您执行以下操作会发生什么？

var vgroup = mainGroup.getChildByName("group1");
if (vgroup != null) {
    trace(vgroup.id)
    var label = vgroup.getChildByName("path1");
    if (label != null) {
        trace(label.id)
        label.text = "change label text"
    }
}

你得到了输出吗？

Actionscript对child元素的引用

1 个答案: