public class WaterWaveView2 extends View {  //存放圓環(huán)的集合  private ArrayList<Wave> mList;  //界面刷新  private Handler mHandler = new Handler() {    @Override    public void handleMessage(Message msg) {      invalidate();//刷新界面,會執(zhí)行onDraw方法    }  };  public WaterWaveView2(Context context) {    this(context, null);  }  public WaterWaveView2(Context context, AttributeSet attrs) {    super(context, attrs);    mList = new ArrayList<Wave>();  }

/*** Created by HongJay on 2016/8/30.* 把wave的數(shù)據(jù)封裝成一個對象*/public class Wave {  public float x;//圓心x坐標(biāo)  public float y;//圓心y坐標(biāo)  public Paint paint; //畫圓的畫筆  public float width; //線條寬度  public int radius; //圓的半徑  public int ranNum;//隨機數(shù)  public int[] randomColor={Color.BLUE,Color.CYAN,      Color.GREEN,Color.MAGENTA,Color.RED,Color.YELLOW};  public Wave(float x, float y) {    this.x = x;    this.y = y;    initData();  }  /**   * 初始化數(shù)據(jù),每次點擊一次都要初始化一次   */  private void initData() {    paint=new Paint();//因為點擊一次需要畫出不同的圓環(huán)    paint.setAntiAlias(true);//打開抗鋸齒    ranNum=(int) (Math.random()*6);//[0,5]的隨機數(shù)    paint.setColor(randomColor[ranNum]);//設(shè)置畫筆的顏色    paint.setStyle(Paint.Style.STROKE);//描邊    paint.setStrokeWidth(width);//設(shè)置描邊寬度    paint.setAlpha(255);//透明度的設(shè)置(0-255),0為完全透明    radius=0;//初始化    width=0;  }}

public boolean onTouchEvent(MotionEvent event) {    super.onTouchEvent(event);    switch (event.getAction()) {      case MotionEvent.ACTION_DOWN:        float x = event.getX();        float y = event.getY();        deleteItem();        Wave wave = new Wave(x, y);        mList.add(wave);        //刷新界面        invalidate();        break;      case MotionEvent.ACTION_MOVE:        float x1 = event.getX();        float y1 = event.getY();        deleteItem();        Wave wave1 = new Wave(x1, y1);        mList.add(wave1);        invalidate();        break;    }    //處理事件    return true;  }  //刪除透明度已經(jīng)為0的圓環(huán)  private void deleteItem(){    for (int i = 0; i <mList.size() ; i++) {      if(mList.get(i).paint.getAlpha()==0){        mList.remove(i);      }    }  }}

protected void onDraw(Canvas canvas) {    super.onDraw(canvas);    //避免程序一運行就進(jìn)行繪制    if (mList.size() > 0) {      //對集合中的圓環(huán)對象循環(huán)繪制      for (Wave wave : mList) {        canvas.drawCircle(wave.x, wave.y, wave.radius, wave.paint);        wave.radius += 3;        //對畫筆透明度進(jìn)行操作        int alpha = wave.paint.getAlpha();        if (alpha < 80) {          alpha = 0;        } else {          alpha -= 3;        }        //設(shè)置畫筆寬度和透明度        wave.paint.setStrokeWidth(wave.radius / 8);        wave.paint.setAlpha(alpha);        //延遲刷新界面        mHandler.sendEmptyMessageDelayed(1, 100);      }    }  }