Flex画箭头

package util {????? ?import flash.display.Graphics; ?import flash.display.Shape; ?import flash.geom.Point; ? ?import mx.containers.Canvas; ?/** ? * 划线工具类 ? * author:songyuanfu ? * */ ?public class LineDescriptor extends Shape {?? ?????????????????? ??????????????? private var _start:Point = new Point(0,0);?? ??????????????? private var _startX:Number;?? ??????????????? private var _startY:Number;?? ?????????????????? ??????????????? private var _end:Point = new Point(0,0);?? ??????????????? private var _endX:Number;?? ??????????????? private var _endY:Number;?? ?????????????????? ??????????????? private var _hasArrowHead:Boolean=false;?? ?????????????????? ??????????????? private var _thinkness:Number = 1;?? ??????????????? private var _color:uint = 0x6E6E6E;?? ??????????????? private var _alpha:Number = 1;?? ??????????????? private var _pixelHinting:Boolean = false;?? ??????????????? private var _scaleMode:String = "normal"; ??????????????? private var _arrow_param:Number;?? ??????????????? ??????????????? /** ???????????????? *? 初始化 ???????????????? * @param startPoint ???????????????? * @param endPoint ???????????????? * @param hasArrow ???????????????? * @param lineColor ???????????????? * @param arrow_param ???????????????? * ???????????????? */??????????????????????????????? ??????????????? public function LineDescriptor(startPoint:Point=null,endPoint:Point=null,hasArrow:Boolean=false,lineColor:uint=0xffffff,arrow_param:Number=1) ??????????????? {?? ??????????????????????? this._color=lineColor; ??????????????????????? start = startPoint;?? ??????????????????????? end = endPoint;?? ??????????????????????? hasArrowHead = hasArrow; ??????????????????????? _arrow_param=arrow_param; ??????????????? } ???????????????? /** ???????????????? *?画线 ???????????????? * @param canvas ???????????????? * ???????????????? */?????????????????????????? ??????????????? public function draw(canvas:Canvas):void ??????????????? {?? ??????????????????????? with(canvas.graphics) ??????????????????????? {?? ??????????????????????????????? lineStyle(_thinkness,_color,_alpha,_pixelHinting,_scaleMode);?? ??????????????????????????????? moveTo(start.x,start.y);? ??????????????????????????????? curveTo((start.x+end.x)/2+20,(start.y+end.y)/2+20,end.x,end.y); ??????????????????????????????? //lineTo(end.x,end.y);????? ??????????????????????? }?? ?????????????????????????? ??????????????????????? if(hasArrowHead) ??????????????????????? {?? ??????????????????????????????? drawArrowHead(canvas);?? ??????????????????????? }?? ??????????????? }?? ??????????????? /**? ???????????????? * 画箭头?? ???????????????? **/? ??????????????? private function drawArrowHead(canvas:Canvas):void ??????????????? { ??????????????? ??//设置让箭头在其3/4处显示 ??????????????? ???if(start.x>end.x) ???????????????? ??{ ???????????????? ???end.x=start.x/4+3*end.x/4; ????????end.y=start.y/4+3*end.y/4; ???????????????? ??} ???????????????? ??else ???????????????? ??{ ???????????????? ???end.x=3*end.x/4+start.x/4; ???????????????? ???end.y=start.y/4+3*end.y/4; ???????????????? ??} ??????????????? ?? ??????????????????????? var startX:Number = start.x;?? ??????????????????????? var startY:Number = start.y;?? ??????????????????????? var endX:Number = end.x;?? ??????????????????????? var endY:Number = end.y;?? ?????????????????????????? ??????????????????????? var arrowLength : Number = 10*_arrow_param;?? ??????????????????????? var arrowAngle : Number = Math.PI / 6;?? ??????????????????????? var lineAngle : Number;?? ??????????????????????? if(endX - startX != 0)???????????????????????????? ??????????????????????????????? lineAngle = Math.atan((endY - startY) / (endX - startX));?? ??????????????????????? else{?? ??????????????????????????????? if(endY - startY < 0)?? ??????????????????????????????????????? lineAngle = Math.PI / 2;?? ??????????????????????????????? else? ??????????????????????????????????????? lineAngle = 3 * Math.PI / 2;?? ??????????????????????? }????????????????????????????????? ??????????????????????? if(endY - startY >= 0 && endX - startX <= 0){?? ??????????????????????????????? lineAngle = lineAngle + Math.PI;?? ??????????????????????? }else if(endY - startY <= 0 && endX - startX <= 0){?? ??????????????????????????????? lineAngle = lineAngle + Math.PI;?? ??????????????????????? }?? ??????????????????????? //定义三角形?? ??????????????????????? var angleC : Number = arrowAngle;?? ??????????????????????? var rimA : Number = arrowLength;?? ??????????????????????? var rimB : Number = Math.pow(Math.pow(endY - startY,2) + Math.pow(endX - startX,2),1/2);?? ??????????????????????? var rimC : Number = Math.pow(Math.pow(rimA,2) + Math.pow(rimB,2) - 2 * rimA * rimB * Math.cos(angleC),1/2);?? ??????????????????????? var angleA : Number = Math.acos((rimB - rimA * Math.cos(angleC)) / rimC);?? ?????????????????????????? ??????????????????????? var leftArrowAngle : Number = lineAngle + angleA;?? ??????????????????????? var rightArrowAngle : Number = lineAngle - angleA;???????????????????????? ??????????????????????? var leftArrowX : Number = startX + rimC * Math.cos(leftArrowAngle);?? ??????????????????????? var leftArrowY : Number = startY + rimC * Math.sin(leftArrowAngle);??????????????????????? ??????????????????????? var rightArrowX : Number = startX + rimC * Math.cos(rightArrowAngle);?? ??????????????????????? var rightArrowY : Number = startY + rimC * Math.sin(rightArrowAngle);?? ?????????????????????????? ?????????????????????????? ??????????????????????? with(canvas.graphics){?? ??????????????????????????????? moveTo(end.x,end.y);?? ??????????????????????????????? lineTo(leftArrowX,leftArrowY);?? ??????????????????????????????? moveTo(end.x,end.y);?? ??????????????????????????????? lineTo(rightArrowX,rightArrowY);?? ??????????????????????? }?? ??????????????? }?? ?????????????????? ??????????????? /**? ???????????????? * 是否有箭头? ???????????????? **/? ??????????????? public function get hasArrowHead():Boolean ??????????????? {?? ??????????????????????? return _hasArrowHead;?? ??????????????? }?? ??????????????? public function set hasArrowHead(value:Boolean):void ??????????????? {?? ??????????????????????? _hasArrowHead = value;?? ??????????????? }?? ?????????????????? ??????????????? /**? ???????????????? * 线的起点? ???????????????? **/? ??????????????? public function get start():Point ??????????????? {?? ??????????????????????? return _start;?? ??????????????? }?? ??????????????? public function set start(value:Point):void ??????????????? {?? ??????????????????????? if(value) ??????????????????????? {?? ??????????????????????????????? _start = value;?? ??????????????????????? }?? ??????????????? }?? ?????????????????? ??????????????? public function get startX():Number ??????????????? {?? ??????????????????????? return _start.x;?? ??????????????? }?? ??????????????? public function set startX(value:Number):void ??????????????? {?? ??????????????????????? _start.x = value;?? ??????????????? }?? ?????????????????? ??????????????? public function get startY():Number ??????????????? {?? ??????????????????????? return _start.y;?? ??????????????? }?? ??????????????? public function set startY(value:Number):void ??????????????? {?? ??????????????????????? _start.y = value;?? ??????????????? }?? ?????????????????? ??????????????? /**? ???????????????? * 线的终点? ???????????????? **/? ??????????????? public function get end():Point ??????????????? {?? ??????????????????????? return _end;?? ??????????????? }?? ??????????????? public function set end(value:Point):void ??????????????? {?? ??????????????????????? if(value) ??????????????????????? {?? ??????????????????????????????? _end = value;?? ??????????????????????? }?? ??????????????? }?? ?????????????????? ??????????????? public function get endX():Number ??????????????? {?? ??????????????????????? return end.x;?? ??????????????? }?? ??????????????? public function set endX(value:Number):void ??????????????? {?? ??????????????????????? _end.x = value;?? ??????????????? }?? ?????????????????? ??????????????? public function get endY():Number ??????????????? {?? ??????????????????????? return end.y;?? ??????????????? }?? ??????????????? public function set endY(value:Number):void ??????????????? {?? ??????????????????????? _end.y = value;?? ??????????????? }?? ?????????????????? ??????? }?? }