如何获取一个显示对象在祖先显示对象之间的总偏移量？

Question

如何获取嵌套容器中的显示对象与舞台或 spark 应用程序等根容器的距离？

例如：

<?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"

                       applicationComplete="applicationCompleteHandler(event)"
                       >


    <fx:Script>
        <![CDATA[

            protected function applicationCompleteHandler(event:FlexEvent):void {
                var point:Point = new Point(nestedButton.x, nestedButton.y);
                var localToGlobalPoint:Point = this.localToGlobal(point);
                var globalToLocalPoint:Point = this.globalToLocal(point);
                var localToContentPoint:Point = this.localToContent(point);

                trace("Button x: " + nestedButton.x);
                trace("Button layout bounds x: " + nestedButton.getLayoutBoundsX());
                trace("Button to main container localToGlobal x: " + localToGlobalPoint.x);
                trace("Button to main container globalToLocal x: " + globalToLocalPoint.x);
                trace("Button to main container localToContent x: " + localToContentPoint.x);
            }

        ]]>
    </fx:Script>

    <mx:Canvas id="mainCanvas" top="10" left="10">
        <mx:Canvas top="10" left="10">
            <s:Group x="10" y="10">
                <s:Button id="sparkButton2" label="spark button" x=10 y="10"/>
            </s:Group>
        </mx:Canvas>
    </mx:Canvas>

</s:WindowedApplication>

如果按钮嵌套在 3 个容器中，并且每个容器与前一个容器的边缘相距 10 像素，并且按钮与其边缘相距 10 像素，则总 x 值应该是40。那不是我得到的价值。每个调用中的 x 值追踪到 0。

Answer 1

似乎没有用于此的 Flash API。所以看起来你拿了两个显示对象并在全局范围内获得它们的位置，然后减去差异。

这是一个函数，它似乎可以正常工作：

public function distanceBetweenDisplayObjects(source:Object, target:Object):Point {
    var sourceRelativePoint:Point;
    var sourceLocalToGlobalPoint:Point;
    var containerLocalToGlobalPoint:Point;
    var x:Number;
    var y:Number;

    var zeroPoint:Point = new Point(0, 0);
    sourceLocalToGlobalPoint = source.localToGlobal(zeroPoint);
    containerLocalToGlobalPoint = target.localToGlobal(zeroPoint);

    var sourceDifference:Point = sourceLocalToGlobalPoint.subtract(containerLocalToGlobalPoint);
    var containerDifference:Point = containerLocalToGlobalPoint.subtract(sourceLocalToGlobalPoint);

    return sourceDifference;
}

用法：

var sourceDifference:Point = distanceBetweenDisplayObjects(nestedButton, mainContainer);

如何获取一个显示对象在祖先显示对象之间的总偏移量？

How do I get the total offset of one display object between an ancestor display object?

actionscript-3

flash

apache-flex