Flash-Flex坐标系统及转换
flash和flex针对不同的目的,提供了3种不同的坐标系。
全局的就是(stage级别的)
本地坐标系(组件级别的)
内容坐标系(相对于本地坐标系说的)
这些坐标系的点是可以转换的,并且有相应的方法,看来adobe想得挺周到。我们一个一个的说一下:
全局
这个坐标系的原点在整个flash舞台的左上角,MouseEvent实例的stageX,stageY就是这个坐标系中的值。
本地
坐标原点是相对的组件的左上角,MouseEvent中的localX,localY就是相对这个坐标系说的。
内容
这个东西比较抽象了UIComponent类实例的contentMouseX 和 contentMouseY 就是了,这个主要针对有滚动条的组件说的,有滚动条了,内容肯定不少,内容所占的区域的坐标就是这个坐标系了。
下面有个官方的图说明了三个坐标系的关系及位置:
.net/art/20091003/r91tmcxl6ZxHY7O.jpg" target="_blank">
坐标转换还有现成的方法:
返回mouse的内容坐标x值 返回mouse的内容坐标Y值 将内容坐标转换成全局坐标 将内容坐标转换成内容坐标 将全局的转成内容坐标 全局的转成本地的 本地到内容坐标 本地到全局坐标
contentMouseX
contentMouseY
contentToGlobal
contentToLocal
globalToContent
globalToLocal
localToContent
localToGlobal
下面是一个小例子:
- <?xml version="1.0"?>
- <!-- containersintroMousePosition.mxml -->
- <mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"
- backgroundColor="white">
- <mx:Script>
- <!--[CDATA[
- import mx.controls.Alert;
- // Handle the mouseDown event generated
- // by clicking in the application.
- private function handleMouseDown(event:MouseEvent):void {
- // Convert the mouse position to global coordinates.
- // The localX and localY properties of the mouse event contain
- // the coordinates at which the event occurred relative to the
- // event target, typically one of the
- // colored internal Canvas controls.
- // A production version of this example could use the stageX
- // and stageY properties, which use the global coordinates,
- // and avoid this step.
- // This example uses the localX and localY properties only to
- // illustrate conversion between different frames of reference.
- var pt:Point = new Point(event.localX, event.localY);
- pt = event.target.localToGlobal(pt);
- // Convert the global coordinates to the content coordinates
- // inside the outer c1 Canvas control.
- pt = c1.globalToContent(pt);
- // Figure out which quadrant was clicked.
- var whichColor:String = "border area";
- if (pt.x < 150) {
- if (pt.y < 150)
- whichColor = "red";
- else
- whichColor = "blue";
- }
- else {
- if (pt.y < 150)
- whichColor = "green";
- else
- whichColor = "magenta";
- }
- Alert.show("You clicked on the " + whichColor);
- }
- ]]-->
- </mx:Script>
- <!-- Canvas container with four child Canvas containers -->
- <mx:Canvas id="c1"
- borderStyle="none"
- width="300" height="300"
- mouseDown="handleMouseDown(event);">
- <mx:Canvas
- width="150" height="150"
- x="0" y="0"
- backgroundColor="red">
- <mx:Button label="I'm in Red"/>
- </mx:Canvas>
- <mx:Canvas
- width="150" height="150"
- x="150" y="0"
- backgroundColor="green">
- <mx:Button label="I'm in Green"/>
- </mx:Canvas>
- <mx:Canvas
- width="150" height="150"
- x="0" y="150"
- backgroundColor="blue">
- <mx:Button label="I'm in Blue"/>
- </mx:Canvas>
- <mx:Canvas
- width="150" height="150"
- x="150" y="150"
- backgroundColor="magenta">
- <mx:Button label="I'm in Magenta"/>
- </mx:Canvas>
- </mx:Canvas>
- </mx:Application>
补充:flash教程,As3.0