Android自定义控件绘制基本图形基础入门

package com.example.viewdemo1.view;import android.content.Context;import android.graphics.Canvas;import android.graphics.Color;import android.graphics.Paint;import android.graphics.Paint.Style;import android.util.AttributeSet;import android.view.View;public class PointView extends View { public PointView(Context context, AttributeSet attrs, int defStyleAttr) {  super(context, attrs, defStyleAttr); } public PointView(Context context, AttributeSet attrs) {  super(context, attrs); } public PointView(Context context) {  super(context); } @Override protected void onDraw(Canvas canvas) {  super.onDraw(canvas);  // 对于画笔  Paint paint = new Paint();  // 设置抗锯齿  paint.setAntiAlias(true);  // 设置画笔颜色  paint.setColor(Color.RED);  // 三种样式  paint.setStyle(Style.FILL_AND_STROKE);  paint.setStrokeWidth(5);  // 阴影  paint.setShadowLayer(10, 0, 0, Color.CYAN);  // 点的坐标 x0,y0,x1,y1......  float[] pts = { 50, 50, 100, 100, 200, 200, 300, 300, 0, 100, 100, 0 };  canvas.drawPoints(pts, paint);  // 绘制点的时候，隔着几个点绘制几个，最多不到多少点  canvas.drawPoints(pts, 1, 6, paint); }}

@Override protected void onDraw(Canvas canvas) {  super.onDraw(canvas);  // 对于画笔  Paint paint = new Paint();  // 设置抗锯齿  paint.setAntiAlias(true);  // 设置画笔颜色  paint.setColor(Color.RED);  // 三种样式  paint.setStyle(Style.FILL);  paint.setStrokeWidth(0.5f);  // 阴影  // paint.setShadowLayer(10, 0, 0, Color.CYAN);  // x0,y0,x1,y1  float[] pts = { 100, 100, 200, 200, 200, 200, 300, 200, 300, 200, 300,    400 };  // 以上是6个点的x,y坐标，两两连成线段  canvas.drawLines(pts, paint);  // 画一条线  canvas.drawLine(0, 0, 100, 100, paint);  }

//指定圆心坐标，半径就OKcanvas.drawCircle(100, 100, 100, paint);

//设置文字大小paint.setTextSize(40);//指定坐标，最好指定文字大小canvas.drawText("哈", 100, 500, paint);//将文字设置到指定路径上Path path = new Path();paint.setTextSize(50);path.addCircle(200, 200, 150, Direction.CCW);canvas.drawTextOnPath("我爱你我的祖国，我爱你我亲爱的姑娘", path, 0, 0, paint);

// 阴影paint.setShadowLayer(10, 0, 0, Color.CYAN);// x y 坐标 及半径值// canvas.drawCircle(100, 100, 50, paint);canvas.drawRect(50, 50, 300, 300, paint);

 //指定放置圆弧的矩形 RectF oval=new RectF(10,10,210,210); //绘制圆弧-0是指开始度数，270是指结束度数 false是指不连接圆心，paint是画笔 canvas.drawArc(oval, 0, 270, false, paint);

//指定矩形，指定画笔canvas.drawOval(oval, paint);