Flex 截图 实例

<?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"
               minWidth="955" minHeight="600">
    <fx:Declarations>
        <!-- Place non-visual elements (e.g., services, value objects) here -->
    </fx:Declarations>
        <fx:Script>
            <![CDATA[
                import mx.events.CloseEvent;
                import mx.managers.PopUpManager;
                import mx.containers.TitleWindow;
                import mx.controls.Alert;
                private var initX:Number;
                private var initY:Number;
                private var borderCan:Canvas;
                
                //测试用图片地址，可以用鼠标拖拽进行选择区域
                
                [Bindable]private var imgPath:String="../images/img8.jpg";
                private function downHander(e:MouseEvent):void{
                    if(borderCan!=null){
                        
                        this.mainCan.removeChild(borderCan);
                    }                                        
                    initX = preUploadImage.mouseX;
                    initY = preUploadImage.mouseY;
                    this.addEventListener(MouseEvent.MOUSE_MOVE,moveHandler);
                    this.addEventListener(MouseEvent.MOUSE_UP,upHander);
                    borderCan =  new Canvas();
                    borderCan.width=1;
                    borderCan.height=1
                    borderCan.setStyle("borderStyle","solid");
                    borderCan.setStyle("borderColor","red");
                    borderCan.x=initX;
                    borderCan.y=initY;
                    this.mainCan.addChild(borderCan);                    
                }
                private var upX:Number;
                private var upY:Number;
                private function upHander(e:MouseEvent):void{
                    upX = borderCan.x
                    upY = borderCan.y
                    this.txtX.text ="X坐标："+upX+" 宽度： "+borderCan.width;
                    this.txtY.text = "Y坐标："+upY+" 高度： "+borderCan.height;
                    this.removeEventListener(MouseEvent.MOUSE_MOVE,moveHandler);
                    this.removeEventListener(MouseEvent.MOUSE_UP,upHander);
                }
                
                private function moveHandler(e:MouseEvent):void{                                
                    this.borderCan.width = this.mainCan.mouseX-initX;
                    this.borderCan.height = this.mainCan.mouseY - initY;                
                }
                
                private var w:Number=0;
                private var h:Number=0;
                private function getImg():void{                
                    w = borderCan.width;
                    h = borderCan.height;
                    //处理截图时候鼠标反向拖拽的坐标问题
                    var finalX:Number=borderCan.x;
                    var finalY:Number=borderCan.y;
                    if(w<0){
                        finalX = borderCan.x + w;
                        w= -w;
                    }
                    if(h<0){                
                        finalY = borderCan.y + h;
                        h= -h;
                    }
                    
                    //用bitmapdata全部获取预览图片的像素
                    var initBD:BitmapData = new BitmapData(preUploadImage.width,preUploadImage.height);
                    initBD.draw(preUploadImage);                
                    var bytearray:ByteArray = new ByteArray();
                    //矩形为要截取区域                
                    var re:Rectangle = new Rectangle(finalX,finalY,w,h);                            
                    bytearray = initBD.getPixels(re); //截取出所选区域的像素集合
                    var imgBD:BitmapData = new BitmapData(w,h);                
                    bytearray.position=0;            //必须的，当前的bytearray.position为最大长度，要设为从0开始读取
                    var fillre:Rectangle = new Rectangle(0,0,w,h);
                    imgBD.setPixels(fillre,bytearray);    //将截取出的像素集合存在新的bitmapdata里，大小和截取区域一样
                    showImg(imgBD);            //显示图片
                }
                
                private function showImg(e:BitmapData):void{
                    var t:TitleWindow = new TitleWindow();
                    t.showCloseButton=true;
                    t.addEventListener(CloseEvent.CLOSE,closeWindow);
                    t.width = w+t.getStyle("borderThickness");
                    t.height =h+t.getStyle("borderThickness")+t.getStyle("headerHeight");
                    var img:Image = new Image();
                    img.width = w;
                    img.height = h; 
                    img.source = new Bitmap(e);
                    t.addChild(img);
                    PopUpManager.addPopUp(t,this,true);
                    PopUpManager.centerPopUp(t);
                }
                private function closeWindow(e:CloseEvent):void{            
                    var t:TitleWindow = e.currentTarget as TitleWindow;                    
                    PopUpManager.removePopUp(t);                
                }
            ]]>
    </fx:Script>
            <mx:Canvas id="mainCan" width="600" height="400" borderColor="white" borderStyle="solid"
                       mouseDown="downHander(event)">    
                <mx:Image id="preUploadImage" width="100%" height="100%" source="{imgPath}">
                </mx:Image>                    
            </mx:Canvas>
            <s:Button x="10" y="410" label="截图" click="getImg()" fontSize="12"/>        
            <s:Label id="txtX" x="100" y="410" text="Label"/>
            <s:Label id="txtY" x="200" y="410" text="Label"/>
</s:Application>