水波纹效果---3环波纹

import android.content.Context;import android.graphics.Bitmap;import android.graphics.Canvas;import android.graphics.Color;import android.graphics.Matrix;import android.graphics.Paint;import android.graphics.PorterDuff;import android.graphics.PorterDuffXfermode;import android.graphics.Bitmap.Config;import android.os.Handler;import android.os.Message;import android.util.DisplayMetrics;import android.util.Log;import android.view.View;import android.view.ViewGroup;import android.widget.ImageView;/** * 水波纹View * @author alan * */public class WaterView extends View{/** * 不透明度（完全透明：0） */private int radius1;private int radius2;private int radius3;private int alpha1;private int alpha2;private int alpha3;private Paint paint1;private Paint paint2;private Paint paint3;private int widthScreen;private int heightScreen;private Handler mHandler;/** * 图片直径 */private  static final int MIN = 50; public WaterView(Context context,Bitmap source) {super(context);init();//获取屏幕的宽高DisplayMetrics dm = getResources().getDisplayMetrics();widthScreen = dm.widthPixels;heightScreen = dm.heightPixels;mHandler = new Handler(){@Overridepublic void handleMessage(Message msg) {super.handleMessage(msg);switch (msg.what) {case 0:flushState();WaterView.this.invalidate();if(alpha1 ==0 ||alpha2 ==0 ||alpha3 ==0){Log.i("TAG", "alpha1-->"+alpha1+"alpha2-->"+alpha2+"alpha3-->"+alpha3);mHandler.sendEmptyMessage(1);}else{mHandler.sendEmptyMessageDelayed(0, 50);}break;case 1:initSimple();WaterView.this.invalidate();mHandler.sendEmptyMessage(0);break;default:break;}}};mHandler.sendEmptyMessage(0);}@Overrideprotected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {// TODO Auto-generated method stubsuper.onMeasure(widthMeasureSpec, heightMeasureSpec);}@Overrideprotected void onDraw(Canvas canvas) {Log.i("TAG", "onDraw......");super.onDraw(canvas);//画圆//c1（最小圆）canvas.drawCircle(widthScreen/2, this.getHeight()/2, radius1, paint1);//c2canvas.drawCircle(widthScreen/2, this.getHeight()/2, radius2, paint2);//c3canvas.drawCircle(widthScreen/2, this.getHeight()/2, radius3, paint3);}private void init() {alpha1 = 255;radius1 = MIN / 2;alpha2= 175;radius2 = MIN / 2 + 80;alpha3 = 95;radius3 = MIN / 2 + 160;initPaint();}private void initSimple(){if(alpha1 == 0 ){alpha1 = 255;radius1 = MIN / 2;paint1.setColor(Color.BLUE);}if(alpha2 == 0 ){alpha2 = 255;radius2 = MIN / 2;paint2.setColor(Color.BLUE);}if(alpha3 == 0 ){alpha3 = 255;radius3 = MIN / 2;paint3.setColor(Color.BLUE);}paint1.setAlpha(alpha1);paint2.setAlpha(alpha2);paint3.setAlpha(alpha3);}private void flushState() {radius1  +=5;alpha1  -=5;//控制速度，值越大，圆环扩大越快radius2  +=5;alpha2  -=5;radius3  +=5;alpha3  -=5;if(alpha1 <= 0){alpha1 = 0 ;}if (alpha2 <= 0) {alpha2 = 0;}if (alpha3 <= 0) {alpha3 = 0;}paint1.setAlpha(alpha1);paint2.setAlpha(alpha2);paint3.setAlpha(alpha3);}private void initPaint() {//新建一个画笔paint1 = new Paint();paint1.setAntiAlias(true);//设置抗锯齿paint1.setStrokeWidth((float) 1);//设置线宽1paint1.setStyle(Paint.Style.STROKE);//设置空心画笔，环形方式绘制paint1.setAlpha(alpha1);paint1.setColor(Color.BLUE);//定义画笔2paint2 = new Paint();paint2.setAntiAlias(true);//设置抗锯齿paint2.setStrokeWidth((float) 1);//设置线宽1paint2.setStyle(Paint.Style.STROKE);//设置空心画笔，环形方式绘制paint2.setAlpha(alpha2);//定义画笔3paint3 = new Paint();paint3.setAntiAlias(true);//设置抗锯齿paint3.setStrokeWidth((float) 1);//设置线宽1paint3.setStyle(Paint.Style.STROKE);//设置空心画笔，环形方式绘制paint3.setAlpha(alpha3);}}