public int width=100;
  public int heigth=100;
  private Paint circlePaint;//画圆
  private Paint textPaint; //画字
  private float availMemory; //已用内存
  private float totalMemory; //总内存
  private String text;  //显示的已用内存百分比
  private boolean isDraging=false; //是否在拖动状态。
  private Bitmap src;
  private Bitmap scaledBitmap; //缩放后的图片。
 /**
   * 初始化画笔以及计算可用内存，总内存，和可用内存百分比。
   */
  public void initPatints() {
    circlePaint = new Paint();
    circlePaint.setColor(Color.CYAN);
    circlePaint.setAntiAlias(true);
    textPaint = new Paint();
    textPaint.setColor(Color.WHITE);
    textPaint.setTextSize(25);
    textPaint.setFakeBoldText(true);
    textPaint.setAntiAlias(true);
    //设置图片
    src = BitmapFactory.decodeResource(getResources(), R.mipmap.ic_launcher);
    //缩放后的图片（将图标设置的和悬浮小球一样大小。）
    scaledBitmap = Bitmap.createScaledBitmap(src, width, heigth, true);
    //计算已用内存，总内存，已用内存百分比，
    availMemory= (float) getAvailMemory(getContext());
    totalMemory= (float) getTotalMemory(getContext());
    text=(int)((availMemory/totalMemory)*100)+"%";
  }

/**
   * 画小球及文字。如果小球是在拖动状态就显示android图标，如果不是拖动状态就显示小球。
   * @param canvas
   */
  @Override
  protected void onDraw(Canvas canvas) {
    if (isDraging){
      canvas.drawBitmap(scaledBitmap,0,0,null);
    }else {
      //1.画圆
      canvas.drawCircle(width / 2, heigth / 2, width / 2, circlePaint);
      //2.画text
      float textwidth = textPaint.measureText(text);//文本宽度
      float x = width / 2 - textwidth / 2;
      Paint.FontMetrics fontMetrics = textPaint.getFontMetrics();

      float dy = -(fontMetrics.ascent + fontMetrics.descent) / 2;
      float y = heigth / 2 + dy;
      canvas.drawText(text, x, y, textPaint);
    }



  }

public long getAvailMemory(Context context)
  {
    // 获取android当前可用内存大小
    ActivityManager am = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);
    ActivityManager.MemoryInfo mi = new ActivityManager.MemoryInfo();
    am.getMemoryInfo(mi);
    //mi.availMem; 当前系统的可用内存
    //return Formatter.formatFileSize(context, mi.availMem);// 将获取的内存大小规格化

    return mi.availMem/(1024*1024);
  }
  public long getTotalMemory(Context context)
  {
    String str1 = "/proc/meminfo";// 系统内存信息文件
    String str2;
    String[] arrayOfString;
    long initial_memory = 0;
    try
    {
      FileReader localFileReader = new FileReader(str1);
      BufferedReader localBufferedReader = new BufferedReader(
          localFileReader, 8192);
      str2 = localBufferedReader.readLine();// 读取meminfo第一行，系统总内存大小
      arrayOfString = str2.split("\\s+");
      for (String num : arrayOfString) {
        Log.i(str2, num + "\t");
      }
      initial_memory = Integer.valueOf(arrayOfString[1]).intValue() * 1024;// 获得系统总内存，单位是KB，乘以1024转换为Byte
      localBufferedReader.close();
    } catch (IOException e) {
    }
    //return Formatter.formatFileSize(context, initial_memory);// Byte转换为KB或者MB，内存大小规格化

    return initial_memory/(1024*1024);
  }

//单例模式创建
 public static FloatViewManager getInstance(Context context){
    if (inStance==null){
      synchronized(FloatViewManager.class){
        if (inStance==null){
          inStance=new FloatViewManager(context);
        }
      }
    }
    return inStance;
  }

/**
   * 展示浮窗
   */
  public void showFloatCircleView(){
  //参数设置
    if (params==null){
      params = new WindowManager.LayoutParams();
      //宽高
      params.width=circleView.width;
      params.height=circleView.heigth;
      //对齐方式
      params.gravity= Gravity.TOP|Gravity.LEFT;
      //偏移量
      params.x=0;
      params.y=0;
      //类型
      params.type=WindowManager.LayoutParams.TYPE_TOAST;
      //设置该window属性。
      params.flags= WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE| WindowManager.LayoutParams.FLAG_NOT_TOUCH_MODAL;
      //像素格式
      params.format= PixelFormat.RGBA_8888;
    }
    //将小球加入窗体中。
    wm.addView(circleView, params);
  }

 public void showFloatCircleView(){
 ......
 }

//给circleView设置touch监听。
  private View.OnTouchListener circleViewOnTouchListener=new View.OnTouchListener() {
    @Override
    public boolean onTouch(View v, MotionEvent event) {
      switch (event.getAction()){
        case MotionEvent.ACTION_DOWN:
        //最后按下时的坐标，根据ACTION_MOVE理解。
          startX = event.getRawX();
          startY = event.getRawY();
          //按下时的坐标。
          downX = event.getRawX();
          downY = event.getRawY();
          break;
        case MotionEvent.ACTION_MOVE:
          circleView.setDrageState(true);
           moveX = event.getRawX();
           moveY=event.getRawY();
          float dx = moveX -startX;
          float dy=moveY-startY;
          params.x+=dx;
          params.y+=dy;
          wm.updateViewLayout(circleView,params);
          startX= moveX;
          startY=moveY;
          break;
        case MotionEvent.ACTION_UP:
          float upx=event.getRawX();
          if (upx>getScreenWidth()/2){
            params.x=getScreenWidth()-circleView.width;
          }else {
            params.x=0;
          }
          circleView.setDrageState(false);
          wm.updateViewLayout(circleView,params);
          if (Math.abs(moveX-downX)>10){
            return true;
          }else {
            return false;
          }
        default:
          break;
      }
      return false;
    }
  };
circleView.setOnTouchListener(circleViewOnTouchListener);
    circleView.setOnClickListener(new View.OnClickListener() {
      @Override
      public void onClick(View v) {
        //Toast.makeText(, "onclick", Toast.LENGTH_SHORT).show();
        //隱藏circleView，顯示菜单栏。
        wm.removeView(circleView);
        showFloatMenuView();
        floatMenuView.startAnimation();
      }
    });

private void initPaint() {
    //画圆画笔
    circlepaint = new Paint();
    circlepaint.setColor(Color.argb(0xff, 0x3a, 0x8c, 0x6c));
    circlepaint.setAntiAlias(true);
    //画进度条画笔
    progerssPaint = new Paint();
    progerssPaint.setAntiAlias(true);
    progerssPaint.setColor(Color.argb(0xff, 0x4e, 0xcc, 0x66));
    progerssPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_IN));//绘制重叠部分
    //画进度画笔
    textPaint = new Paint();
    textPaint.setAntiAlias(true);
    textPaint.setColor(Color.WHITE);
    textPaint.setTextSize(25);

    //画布
    bitmap = Bitmap.createBitmap(width, heigth, Bitmap.Config.ARGB_8888);
    bitmapCanvas = new Canvas(bitmap);
    //手势监听。
    gestureDetector = new GestureDetector(new MyGertureDetectorListener());
    setOnTouchListener(new OnTouchListener() {
      @Override
      public boolean onTouch(View v, MotionEvent event) {
        return gestureDetector.onTouchEvent(event);
      }
    });
    //设置view可以点击。
    setClickable(true);
  }
  class MyGertureDetectorListener extends GestureDetector.SimpleOnGestureListener{
    @Override
    public boolean onDoubleTap(MotionEvent e) {
    ......
     //双击事件的逻辑
      return super.onDoubleTap(e);
    }

    @Override
    public boolean onSingleTapConfirmed(MotionEvent e) {
    ......
     //单击事件的逻辑
      return super.onSingleTapConfirmed(e);
    }
  }

//单击事件发送周期handler.
private void startSingleTapAnimation() {
    handler.postDelayed(singleTapRunnable,200); 
  }
  private SingleTapRunnable singleTapRunnable=new SingleTapRunnable();
  class SingleTapRunnable implements Runnable{
    @Override
    public void run() {
      count--;
      if (count>=0) {
        invalidate();//不断进行重绘。
        handler.postDelayed(singleTapRunnable,200);
      }else {
        handler.removeCallbacks(singleTapRunnable);
        count=50;
      }
    }
  }
  //双击事件发送周期handler。
  private void startDoubleTapAnimation() {
    handler.postDelayed(runnbale,50);
  }
  private DoubleTapRunnable runnbale=new DoubleTapRunnable();

  class DoubleTapRunnable implements Runnable{
    @Override
    public void run() {
      num--;
      if (num>=0){
        invalidate();//不断进行重绘。
        handler.postDelayed(runnbale,50);
      }else {
        handler.removeCallbacks(runnbale);
        //释放内存。
       killprocess();
       //计算释放后的已用内存百分比。
        num=(int)(((float)currentProgress/max)*100);
      }
    }
  }

首先是小球的绘制，和波纹路径的绘制。
//绘制小球
    bitmapCanvas.drawCircle(width / 2, heigth / 2, width / 2, circlepaint);
    //根据path,绘制波纹路径。每次绘制前将上次的path,reset.
    path.reset();
    float y =(1-(float)num/100)*heigth;
    path.moveTo(width, y);
    path.lineTo(width, heigth);
    path.lineTo(0, heigth);
    path.lineTo(0, y);

 if (!isSingleTap){
    float d=(1-(float)num/(100/2))*10;
      for (int i=0;i<3;i++){
      path.rQuadTo(10,-d,20,0);
      path.rQuadTo(10,d,20,0);
       }
    }else {
      float d=(float)count/50*10;
      if (count%2==0){
        for (int i=0;i<=3;i++){
          path.rQuadTo(10,-d,30,0);
          path.rQuadTo(10,d,30,0);
        }
      }else {
        for (int i=0;i<=3;i++){
          path.rQuadTo(10,d,30,0);
          path.rQuadTo(10,-d,30,0);
        }

      }
    }

public void killprocess(){
    ActivityManager activityManger=(ActivityManager) getContext().getSystemService(Context.ACTIVITY_SERVICE);
    List<ActivityManager.RunningAppProcessInfo> list=activityManger.getRunningAppProcesses();
    if(list!=null)
      for(int i=0;i<list.size();i++)
      {
        ActivityManager.RunningAppProcessInfo apinfo=list.get(i);
        String[] pkgList=apinfo.pkgList;
 if(apinfo.importance>ActivityManager.RunningAppProcessInfo.IMPORTANCE_SERVICE)
        {
          // Process.killProcess(apinfo.pid);
          for(int j=0;j<pkgList.length;j++) {
            boolean flag=pkgList[j].contains("com.example.yyh.animation360");//这里要判断是否为当前应用，要不然也可能会结束当前应用。
            if(!flag){
            activityManger.killBackgroundProcesses(pkgList[j]);
          }
          }
        }
      }

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
  android:orientation="vertical"
  android:layout_width="match_parent"
  android:layout_height="match_parent"
  android:background="#33000000"
  >
  <LinearLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="vertical"
    android:background="#F02F3942"
    android:layout_alignParentBottom="true"
    android:id="@+id/ll"
    android:clickable="true"
    >
    <LinearLayout
      android:layout_width="match_parent"
      android:layout_height="wrap_content"
      android:orientation="horizontal"
      >
      <ImageView
        android:layout_width="50dp"
        android:layout_height="50dp"
        android:src="@mipmap/ic_launcher"
        android:layout_gravity="center_vertical"
        />
      <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textSize="15sp"
        android:textColor="#c93944"
        android:text="360加速球"
        android:layout_gravity="center_vertical"
        />
    </LinearLayout>
    <com.example.yyh.animation360.view.MyProgreeView
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:layout_gravity="center_horizontal"
      android:layout_marginTop="10dp"
      />
  </LinearLayout>
</RelativeLayout>

 View view =View.inflate(getContext(), R.layout.float_menuview,null);
    LinearLayout linearLayout= (LinearLayout) view.findViewById(R.id.ll);
    translateAnimation = new TranslateAnimation(Animation.RELATIVE_TO_SELF,0,Animation.RELATIVE_TO_SELF,0,Animation.RELATIVE_TO_SELF,1.0f,Animation.RELATIVE_TO_SELF,0);
    translateAnimation.setDuration(500);
    translateAnimation.setFillAfter(true);
    linearLayout.setAnimation(translateAnimation);
    view.setOnTouchListener(new OnTouchListener() {
      @Override
      public boolean onTouch(View v, MotionEvent event) {
        FloatViewManager manager=FloatViewManager.getInstance(getContext());
        manager.hideFloatMenuView();
        manager.showFloatCircleView();
        return false;
      }
    });
    addView(view);

public class MyFloatService extends Service {
  @Nullable
  @Override
  public IBinder onBind(Intent intent) {
    return null;
  }
  @Override
  public void onCreate() {
    //用来开启FloatViewManager
    FloatViewManager manager=FloatViewManager.getInstance(this);
    manager.showFloatCircleView();
    super.onCreate();
  }

}

public class MainActivity extends AppCompatActivity {
  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
  }
  public void startService(View view){
    Intent intent=new Intent(this, MyFloatService.class);
    startService(intent);
    finish();
  }
}