如何在viewstack中设置选中的子项？

Question

在main.mxml中：

    public function init():void
    {
       PopUpManager.createPopUp(this,login,true);
    }
    <mx:ViewStack id="vs" label="content" >
      <local:FrontPanel id="Fpanel" />
      <local:SlavePanel id="Spanel" />
      <local:AdminPanel id="Mpanel" />  
    </mx:ViewStack> 

在Login.mxml中：

public function authenticateRH(event:ResultEvent):void
    {
        var replyMsg:String=event.result as String;     

        switch(replyMsg)
        {
            case "Master" :
                here i want invoke Mpanel from Main.mxml
                break;

            case "Slave" :
                    here i want invoke Spanel from Main.mxml 
                break;

            case "fail" :
                Alert.show("Login Incorrect!!");
                return;
        }      
   }

如何从login.mxml中选择main.mxml的视图堆栈的子级？

Answer 1

我会使用事件(和接口)，这样你的表单就不需要知道太多关于它们的信息。它还可以让你更好地控制弹出窗口关闭后发生的事情(IMHO)。

这里有一个小示例(如果我可以正确地粘贴代码)。这个例子没有使用一个可以帮助解耦的接口。我还使用了动态事件来加快原型设计速度，但您可能希望定义一个正式事件。

模拟你的main：

        import mx.events.DynamicEvent;
    import mx.managers.PopUpManager;

    private function btnClick(e:Event):void
    {
        vs.selectedIndex = 0;

        var myLogin:myPopup = new myPopup();
        myLogin.addEventListener
                (
                    "WAS_CLOSED",
                    function(e:DynamicEvent):void { vs.selectedIndex = e.byButton; }
                );

        PopUpManager.addPopUp(myLogin, this, true);
        PopUpManager.centerPopUp(myLogin);
    }

模拟您的登录：

        import mx.events.DynamicEvent;
    import mx.managers.PopUpManager;

    private var eClose:DynamicEvent = new DynamicEvent("WAS_CLOSED");

    private function closeMe(byButton:int):void
    {
        eClose.byButton = byButton;
        dispatchEvent(eClose);
        PopUpManager.removePopUp(this);
    }

<mx:Button x="122" y="250" label="Thing 1" click="closeMe(1);" />
<mx:Button x="195" y="250" label="Thing 2" click="closeMe(2);" />

Answer 2

public function init():void
{
   var popup:IFlexDisplayObject = PopUpManager.createPopUp(this, Login, true);
   popup.addEventListener(Event.SELECT, onSelect);
}
private function onSelect(e:CustomEvent):void
{
    if(e.item == CustomEvent.MASTER)
    {
        vs.selectedItem = Mpanel;
    }
    else if(e.item == CustomEvent.SLAVE)
    {
        vs.selectedItem = Spanel;
    }
    //remove popup
    PopUpManager.removePopUp(IFlexDisplayObject(e.target));
}

//Login.mxml :
public function authenticateRH(event:ResultEvent):void
{
    var replyMsg:String=event.result as String;             

    switch(replyMsg)
    {
            case "Master" :
                    dispatchEvent(new CustomEvent(CustomEvent.MASTER));
                    break;

            case "Slave" :
                    dispatchEvent(new CustomEvent(CustomEvent.MASTER));
                    break;
            case "fail" :
                    //remove popup
                    PopUpManager.removePopUp(this);
                    Alert.show("Login Incorrect!!");
                    return;
    }      
}
//CustomEvent.as
public class CustomEvent extends Event
{
    public static const MASTER:String = "master";
    public static const SLAVE:String = "slave";
    public var item:String;
    public function CustomEvent(item:String)
    {
        super(Event.SELECT);
        this.item = item;
    }
}

Answer 3

我假设您的问题是在authenticateRH方法中没有对ViewStack的引用。解决此问题的一种方法是在创建登录弹出窗口后为其提供更多信息：

public function init():void
{
    var loginPopup:login = PopUpManager.createPopUp(this,login,true) as login;                                      
    loginPopup.setUsefulInformation(referenceToViewStack);
}

您必须将setUsefulInformation()方法添加到login.mxml。你想传递什么信息来解决这个问题，这取决于你。