在Flex应用程序中扭曲图像控件

这例子告诉大家怎么利用Transform和Maxtrix两个类来在水平和垂直方向上扭曲图像控件。
源代码如下：

<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"
        layout="vertical"
        verticalAlign="middle"
        backgroundColor="white" viewSourceURL="srcview/index.html">

    <mx:Script>
        <![CDATA[
            private function radiansToDegrees(radians:Number):Number {
                return (radians * (180 / Math.PI));
            }

            private function degreesToRadians(degrees:Number):Number {
                return (degrees * (Math.PI / 180));
            }

            private function skewr(target:DisplayObject):void {
                var m:Matrix = target.transform.matrix;
                m.b = Math.tan(degreesToRadians(sliderY.value));
                m.c = Math.tan(degreesToRadians(sliderX.value));

                var t:Transform = new Transform(target);
                t.matrix = m;

                target.transform = t;
            }

            private function resetMatrix(target:DisplayObject):void {
                // Reset sliders.
                sliderX.value = 0;
                sliderY.value = 0;
                skewr(target);
            }
        ]]>
    </mx:Script>

    <mx:ApplicationControlBar dock="true">
        <mx:Form styleName="plain">
            <mx:FormItem label="skew X:">
                <mx:HSlider id="sliderX"
                        minimum="-15"
                        maximum="15"
                        value="0"
                        liveDragging="true"
                        snapInterval="1"
                        change="skewr(image);" />
            </mx:FormItem>
            <mx:FormItem label="skew Y:">
                <mx:HSlider id="sliderY"
                        minimum="-15"
                        maximum="15"
                        value="0"
                        liveDragging="true"
                        snapInterval="1"
                        change="skewr(image);" />
            </mx:FormItem>
            <mx:FormItem>
                <mx:Button label="Reset"
                        click="resetMatrix(image);" />
            </mx:FormItem>
        </mx:Form>
    </mx:ApplicationControlBar>

    <mx:Image id="image"
            source="@Embed('Fx.png')"
            scaleContent="true"
            maintainAspectRatio="true"
            width="200"
            height="200" />

</mx:Application>

效果如下：