apache-flex - 如何在Flex应用程序边界内保持拖动的TitleWindow

Question

我在FB4中使用PopupManager来显示自定义对话框。

popw​​in =新的TitleWindow();
popw​​in.addElement(myCustomDialog);
PopUpManager.addPopUp(popwin，this，false);
PopUpManager.centerPopUp(popwin);

可以拖动弹出的TitleWindow，并在其灰色标题栏位于Flex应用程序矩形的边界之外时放开它，然后无法再次捕获弹出窗口。也可以将TitleWindow向下拖动，以使其在Flex应用矩形的底部边缘下方完全不可见。当Flex应用范围小于整个浏览器窗口且用户正在快速工作时，发生这种情况的机会就会增加。是否有一个简单的设置可以阻止这种情况发生，还是程序员必须在拖动操作期间拦截该行为？

谢谢
提姆

Answer 1

嘿，据我所知，没有一个简单的设置可以阻止这种情况的发生。您需要做的就是每次运动时观察它，并确保它保持在一定范围内。然后，您可以根据需要将该事件处理程序抽象为某些Controller类。

这是一个基本示例:

<?xml version="1.0" encoding="utf-8"?>
<s:Application 
    xmlns:fx="http://ns.adobe.com/mxml/2009"
    xmlns:s="library://ns.adobe.com/flex/spark"
    xmlns:mx="library://ns.adobe.com/flex/mx"
    creationComplete="creationCompleteHandler()">

    <fx:Script>
        <![CDATA[
            import flash.geom.Rectangle;
            import mx.core.FlexGlobals;
            import mx.core.UIComponent;
            import mx.events.MoveEvent;
            import mx.managers.PopUpManager;
            import spark.components.TitleWindow;

            protected function creationCompleteHandler():void
            {
                var window:TitleWindow = new TitleWindow();
                PopUpManager.addPopUp(window, this, false);
                PopUpManager.centerPopUp(window);
                window.addEventListener(MoveEvent.MOVE, window_moveHandler);
            }

            protected function window_moveHandler(event:MoveEvent):void
            {
                var window:UIComponent = event.currentTarget as UIComponent;
                var application:UIComponent = FlexGlobals.topLevelApplication as UIComponent;
                var bounds:Rectangle = new Rectangle(0, 0, application.width, application.height);
                var windowBounds:Rectangle = window.getBounds(application);
                var x:Number;
                var y:Number;
                if (windowBounds.left <= bounds.left)
                    x = bounds.left;
                else if (windowBounds.right >= bounds.right)
                    x = bounds.right - window.width;
                else
                    x = window.x;
                if (windowBounds.top <= bounds.top)
                    y = bounds.top;
                else if (windowBounds.bottom >= bounds.bottom)
                    y = bounds.bottom - window.height;
                else
                    y = window.y;
                window.move(x, y);
            }

        ]]>
    </fx:Script>

</s:Application>

希望能有所帮助，
槊