Android画图Path类的使用

package com.javaeye.android.my;              import android.app.Activity;     import android.os.Bundle;     import android.view.View;     import android.content.Context;     import android.graphics.Canvas;     import android.graphics.Color;     import android.graphics.Paint;     import android.graphics.RectF;     import android.graphics.Path;     import android.graphics.Shader;     import android.graphics.LinearGradient;       //主程序中继承自Android.view.View的 MyView类，重写 MyView的onDraw（）方法，      //一开始就会运行绘制的工作，在onDraw（）中以Paint将几何图形绘制在Canvas上，      //以 paint.setColor() 改变图形颜色、以 paint.setStyle()的设置来控制画出的的      //图形是空心还是实心。程序的最后一段，就是直接在Canvas写上文字，随着Paint对      //象里的属性设置，也会有不同的外观模式。     public class GraphicesActivity extends Activity {         /** Called when the activity is first created. */        @Override        public void onCreate(Bundle savedInstanceState) {             super.onCreate(savedInstanceState);             /*设置ContentView为自定义的MyVieW*/            MyView myView=new MyView(this);             setContentView(myView);         }                   /* 自定义继承View 的MyView*/        private class MyView extends View {              public MyView(Context context){                 super(context) ;              }                            /*重写onDraw（）*/             @Override             protected void onDraw(Canvas canvas)              {                      super.onDraw(canvas);                   /*设置背景为白色*/                  canvas.drawColor(Color.WHITE);                                       Paint paint=new Paint();                   /*去锯齿*/                  paint.setAntiAlias(true);                   /*设置paint的颜色*/                  paint.setColor(Color.RED);                   /*设置paint的 style 为STROKE：空心*/                  paint.setStyle(Paint.Style.STROKE);                   /*设置paint的外框宽度*/                  paint.setStrokeWidth(3);                                       /*画一个空心圆形*/                  canvas.drawCircle(40, 40, 30, paint);                   /*画一个空心正方形*/                  canvas.drawRect(10, 90, 70, 150, paint);                   /*画一个空心长方形*/                  canvas.drawRect(10, 170, 70,200, paint);                   /*画一个空心椭圆形*/                  canvas.drawOval(new RectF(10,220,70,250), paint);                   /*画一个空心三角形*/                  Path path=new Path();                   path.moveTo(10, 330);                   path.lineTo(70,330);                   path.lineTo(40,270);                   path.close();                   canvas.drawPath(path, paint);                   /*画一个空心梯形*/                  Path path1=new Path();                   path1.moveTo(10, 410);                   path1.lineTo(70,410);                   path1.lineTo(55,350);                   path1.lineTo(25, 350);                   path1.close();                   canvas.drawPath(path1, paint);                                       /*设置paint的颜色*/                  paint.setColor(Color.BLUE);                   /*设置paint 的style为 FILL：实心*/                  paint.setStyle(Paint.Style.FILL);                   /*画一个实心圆*/                  canvas.drawCircle(120,40,30, paint);                   /*画一个实心正方形*/                  canvas.drawRect(90, 90, 150, 150, paint);                   /*画一个实心长方形*/                  canvas.drawRect(90, 170, 150,200, paint);                   /*画一个实心椭圆*/                  RectF re2=new RectF(90,220,150,250);                   canvas.drawOval(re2, paint);                   /*画一个实心三角形*/                  Path path2=new Path();                   path2.moveTo(90, 330);                   path2.lineTo(150,330);                   path2.lineTo(120,270);                   path2.close();                   canvas.drawPath(path2, paint);                   /*画一个实心梯形*/                  Path path3=new Path();                   path3.moveTo(90, 410);                   path3.lineTo(150,410);                   path3.lineTo(135,350);                   path3.lineTo(105, 350);                   path3.close();                   canvas.drawPath(path3, paint);                                       /*设置渐变色*/                  Shader mShader=new LinearGradient(0,0,100,100,                           new int[]{Color.RED,Color.GREEN,Color.BLUE,Color.YELLOW},                           null,Shader.TileMode.REPEAT);                   //Shader.TileMode三种模式                    //REPEAT:沿着渐变方向循环重复                    //CLAMP:如果在预先定义的范围外画的话，就重复边界的颜色                    //MIRROR:与REPEAT一样都是循环重复，但这个会对称重复                    paint.setShader(mShader);//用Shader中定义定义的颜色来话                                     /*画一个渐变色圆*/                  canvas.drawCircle(200,40,30, paint);                   /*画一个渐变色正方形*/                  canvas.drawRect(170, 90, 230, 150, paint);                   /*画一个渐变色长方形*/                  canvas.drawRect(170, 170, 230,200, paint);                   /*画一个渐变色椭圆*/                  RectF re3=new RectF(170,220,230,250);                   canvas.drawOval(re3, paint);                   /*画一个渐变色三角形*/                  Path path4=new Path();                   path4.moveTo(170,330);                   path4.lineTo(230,330);                   path4.lineTo(200,270);                   path4.close();                   canvas.drawPath(path4, paint);                   /*画一个渐变色梯形*/                  Path path5=new Path();                   path5.moveTo(170, 410);                   path5.lineTo(230,410);                   path5.lineTo(215,350);                   path5.lineTo(185, 350);                   path5.close();                   canvas.drawPath(path5, paint);                                       /*写字*/                  paint.setTextSize(24);                   canvas.drawText("圆形", 240, 50, paint);                   canvas.drawText("正方形", 240, 120, paint);                   canvas.drawText("长方形", 240, 190, paint);                   canvas.drawText("椭圆形", 240, 250, paint);                   canvas.drawText("三角形", 240, 320, paint);                   canvas.drawText("梯形", 240, 390, paint);                }         }     }   

原文链接：http://www.linuxidc.com/Linux/2011-12/49307.htm