再学AS3(五)：鼠绘.docx

再学AS3（五）：鼠绘知识点：1、添加鼠标监听事件MouseEvent；2、规定画布大小；3、moveTo和lineTo；4、绘制开始与结束判断。代码：var huabu:Sprite=new Sprite(); huabu.graphics.beginFill(0xFFFFFF); huabu.graphics.drawRect(20,20,510,360); huabu.graphics.endFill(); addChild(huabu); var _drawing:Boolean; var quxian:Sprite=new Sprite(); quxian.graphics.lineStyle( 2, 0xFF0000 ); huabu.addChild(quxian); _drawing = false; huabu.addEventListener( MouseEvent.MOUSE_DOWN, startDrawing ); huabu.addEventListener( MouseEvent.MOUSE_MOVE,moving); huabu.addEventListener( MouseEvent.MOUSE_UP, stopDrawing ); stage.addEventListener(MouseEvent.MOUSE_UP,stopDrawing); function startDrawing( event:MouseEvent ):void quxian.graphics.moveTo( mouseX, mouseY ); _drawing = true; function moving( event:MouseEvent ):void if ( _drawing ) quxian.graphics.lineTo( mouseX, mouseY ); function stopDrawing( event:MouseEvent ):void _drawing = false; （2）：直线知识点：1、添加鼠标监听事件MouseEvent；2、规定画布大小；3、moveTo和lineTo；4、绘制开始与结束判断。难点：绘制多条直线代码：var huabu:Sprite=new Sprite(); huabu.graphics.beginFill(0xFFFFFF); huabu.graphics.drawRect(20,20,510,360); huabu.graphics.endFill(); addChild(huabu); var _drawing:Boolean=false; var zhixian:Sprite=new Sprite(); huabu.addChild(zhixian); var _color:Number=0xFF0000; var zx:int=1; var ys_x:Number; var ys_y:Number; huabu.addEventListener( MouseEvent.MOUSE_DOWN, startDrawing ); huabu.addEventListener( MouseEvent.MOUSE_MOVE,moving); huabu.addEventListener( MouseEvent.MOUSE_UP, stopDrawing ); stage.addEventListener( MouseEvent.MOUSE_UP, stopDrawing ); function startDrawing( event:MouseEvent ):void ys_x=mouseX; ys_y=mouseY; _drawing = true; function moving( event:MouseEvent ):void if (_drawing) huabu.removeChild(zhixian); zhixian=new Sprite(); zhixian.graphics.lineStyle( zx, _color ); zhixian.graphics.moveTo(ys_x,ys_y); zhixian.graphics.lineTo(mouseX,mouseY); huabu.addChild(zhixian); function stopDrawing( event:MouseEvent ):void zhixian=new Sprite(); huabu.addChild(zhixian); /没有以上两句，只能画一条直线 _drawing = false; （3）：圆知识点：1、添加鼠标监听事件MouseEvent；2、绘制过程中显示半径（两点间的距离Point.distance(坐标1,坐标2)）；3、drawCircle、moveTo和lineTo；4、绘制开始与结束判断。难点：绘制多个圆代码：var _drawing:Boolean; var yuan:Sprite=new Sprite(); addChild(yuan); var banjing:Sprite=new Sprite(); addChild(banjing); var yuanxin_x:Number; var yuanxin_y:Number; var zuobiao1:Point; var zuobiao2:Point; var bj:Number; _drawing = false; stage.addEventListener( MouseEvent.MOUSE_DOWN, startDrawing ); stage.addEventListener( MouseEvent.MOUSE_MOVE,yd); stage.addEventListener( MouseEvent.MOUSE_UP, stopDrawing ); function startDrawing( event:MouseEvent ):void yuanxin_x=mouseX;/鼠标按下的位置就是圆心的位置 yuanxin_y=mouseY; _drawing = true; function yd( event:MouseEvent ):void if ( _drawing ) zuobiao1 = new Point(yuanxin_x,yuanxin_y); zuobiao2 = new Point(mouseX, mouseY); bj= Point.distance(zuobiao1, zuobiao2);/显示两点之间的距离即为半径 removeChild(yuan); yuan=new Sprite(); yuan.graphics.lineStyle( 2, 0xFF0000 ); yuan.graphics.drawCircle(yuanxin_x,yuanxin_y,bj); addChild(yuan); removeChild(banjing); banjing=new Sprite(); banjing.graphics.lineStyle(2,0xFF0000,0.5); banjing.graphics.moveTo(yuanxin_x,yuanxin_y); banjing.graphics.lineTo(mouseX,mouseY); addChild(banjing); function stopDrawing( event:MouseEvent ):void removeChild(banjing);/绘制结束时半径线消失 banjing=new Sprite();/每次画圆过程中都显示半径 addChild(banjing); yuan=new Sprite();/可绘制多个圆 addChild(yuan); _drawing = false; （4）：椭圆知识点：1、添加鼠标监听事件MouseEvent和键盘监听事件KeyboardEvent；2、椭圆的宽与高；3、drawEllipse；4、绘制开始与结束判断；5、按下Shift键绘制正圆。难点：按下Shift键绘制正圆代码：var _drawing:Boolean=false; var ellipse:Sprite=new Sprite(); addChild(ellipse); var kaishi_x:Number; var kaishi_y:Number; var w:Number; var h:Number; var _max:Number; stage.addEventListener( MouseEvent.MOUSE_DOWN, startDrawing ); stage.addEventListener( MouseEvent.MOUSE_MOVE,moving); stage.addEventListener( MouseEvent.MOUSE_UP, stopDrawing ); function startDrawing( event:MouseEvent ):void kaishi_x=mouseX; kaishi_y=mouseY; _drawing = true; function moving( event:MouseEvent ):void if (_drawing) w=mouseX-kaishi_x; h=mouseY-kaishi_y; removeChild(ellipse); ellipse=new Sprite(); ellipse.graphics.lineStyle( 2, 0xFF0000 ); ellipse.graphics.drawEllipse(kaishi_x,kaishi_y,w,h); addChild(ellipse); function stopDrawing( event:MouseEvent ):void ellipse=new Sprite(); addChild(ellipse); _drawing = false; stage.focus=this; stage.addEventListener(KeyboardEvent.KEY_DOWN, shift); function shift(event:KeyboardEvent):void if (event.charCode=0) if (_drawing) w=mouseX-kaishi_x; h=mouseY-kaishi_y; _max=Math.max(Math.abs(w),Math.abs(h); if (w0 & h0 & h0) w=_max; h=_max; if (w0) w=-_max; h=_max; if (w0 & h0) w=_max; h=-_max; removeChild(ellipse); ellipse=new Sprite(); ellipse.graphics.lineStyle( 2, 0xFF0000 ); ellipse.graphics.drawEllipse(kaishi_x,kaishi_y,w,h); addChild(ellipse); （5）：矩形知识点：1、添加鼠标监听事件MouseEvent和键盘监听事件KeyboardEvent；2、椭圆的宽与高；3、drawRect；4、绘制开始与结束判断；5、按下Shift键绘制正方形。难点：按下Shift键绘制正方形代码：var _drawing:Boolean=false; var _drawrect:Sprite=new Sprite(); addChild(_drawrect); var yx_x:Number; var yx_y:Number; var w:Number; var h:Number; var _max:Number; stage.addEventListener( MouseEvent.MOUSE_DOWN, startDrawing ); stage.addEventListener( MouseEvent.MOUSE_MOVE,moving); stage.addEventListener( MouseEvent.MOUSE_UP, stopDrawing ); function startDrawing( event:MouseEvent ):void yx_x=mouseX; yx_y=mouseY; _drawing = true; function moving( event:MouseEvent ):void if (_drawing) w=mouseX-yx_x; h=mouseY-yx_y; removeChild(_drawrect); _drawrect=new Sprite(); _drawrect.graphics.lineStyle( 2, 0xFF0000 ); _dra