Android Path的应用

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);              }       }   }