@Override
  public void update() {
    super.update();
    LayoutParams lp = (LayoutParams) getLayoutParams();
    lp.leftMargin = bounds.displayLeft;
    lp.topMargin = bounds.displayTop;
    setLayoutParams(lp);

    Log.d("Chevron", "new size:" + this.getWidth() + "," + this.getHeight());

    updatePath();
  }
  private void initUI() {
    mWM = (WindowManager) getSystemService(Context.WINDOW_SERVICE);
    mScreenWidth = mWM.getDefaultDisplay().getWidth();
    mScreenHeight = mWM.getDefaultDisplay().getHeight();
    //		1找控件
    final ImageView iv_drag = (ImageView) findViewById(R.id.iv_drag);
    final Button bt_notify_top = (Button) findViewById(R.id.bt_notify_top);
    final Button bt_notify_bottom = (Button) findViewById(R.id.bt_notify_bottom);

    //		2获取归属地提示框保存的位置
    int locationX = SpUtil.getInt(this, ConstantValues.TOAST_ADDRESS_LOCATIONX, 0);
    int locationY = SpUtil.getInt(this, ConstantValues.TOAST_ADDRESS_LOCATIONY, 0);
    mLayoutParams =
        new RelativeLayout.LayoutParams(
            RelativeLayout.LayoutParams.WRAP_CONTENT, RelativeLayout.LayoutParams.WRAP_CONTENT);
    mLayoutParams.leftMargin = locationX;
    mLayoutParams.topMargin = locationY;
    iv_drag.setLayoutParams(mLayoutParams);

    if (locationY < mScreenHeight / 2) {
      bt_notify_top.setVisibility(View.INVISIBLE);
      bt_notify_bottom.setVisibility(View.VISIBLE);
    } else {
      bt_notify_top.setVisibility(View.VISIBLE);
      bt_notify_bottom.setVisibility(View.INVISIBLE);
    }

    //		4设置触摸监听事件
    iv_drag.setOnTouchListener(
        new OnTouchListener() {
          private int startX;
          private int startY;

          @Override
          public boolean onTouch(View v, MotionEvent event) {
            switch (event.getAction()) {
              case MotionEvent.ACTION_DOWN:
                //					获取按下时候的坐标,作为初始坐标
                startX = (int) event.getRawX();
                startY = (int) event.getRawY();

                break;
              case MotionEvent.ACTION_MOVE:
                //					获取移动过程中的坐标
                int moveX = (int) event.getRawX();
                int moveY = (int) event.getRawY();
                //					移动的距离
                int disX = moveX - startX;
                int disY = moveY - startY;

                int left = iv_drag.getLeft() + disX;
                int top = iv_drag.getTop() + disY;
                int right = iv_drag.getRight() + disX;
                int bottom = iv_drag.getBottom() + disY;

                if (top < mScreenHeight / 2) {
                  bt_notify_top.setVisibility(View.INVISIBLE);
                  bt_notify_bottom.setVisibility(View.VISIBLE);
                } else {
                  bt_notify_top.setVisibility(View.VISIBLE);
                  bt_notify_bottom.setVisibility(View.INVISIBLE);
                }

                //					1容错处理
                if (left < 0 || top < 0 || right > mScreenWidth || bottom > mScreenHeight - 22) {
                  return true;
                }
                //					2将移动后的坐标展示
                System.out.println(left + "----" + top + "----" + right + "----" + bottom);
                iv_drag.layout(left, top, right, bottom);
                //					3重置起始坐标
                startX = (int) event.getRawX();
                startY = (int) event.getRawY();
                break;
              case MotionEvent.ACTION_UP:
                //					4保存吐司位置坐标
                SpUtil.putInt(
                    getApplicationContext(),
                    ConstantValues.TOAST_ADDRESS_LOCATIONX,
                    iv_drag.getLeft());
                SpUtil.putInt(
                    getApplicationContext(),
                    ConstantValues.TOAST_ADDRESS_LOCATIONY,
                    iv_drag.getTop());

                break;
            }
            return false;
          }
        });

    //		5设置双击监听事件
    iv_drag.setOnClickListener(
        new OnClickListener() {

          @Override
          public void onClick(View v) {
            System.arraycopy(mHits, 1, mHits, 0, mHits.length - 1);
            mHits[mHits.length - 1] = SystemClock.uptimeMillis();
            if (mHits[mHits.length - 1] - mHits[0] < 500) {
              // 满足双击事件后,调用代码
              int left = mScreenWidth / 2 - iv_drag.getWidth() / 2;
              int top = mScreenHeight / 2 - iv_drag.getHeight() / 2;
              int right = mScreenWidth / 2 + iv_drag.getWidth() / 2;
              int bottom = mScreenHeight / 2 + iv_drag.getHeight() / 2;

              // 控件按以上规则显示
              iv_drag.layout(left, top, right, bottom);

              // 存储最终位置
              SpUtil.putInt(
                  getApplicationContext(),
                  ConstantValues.TOAST_ADDRESS_LOCATIONX,
                  iv_drag.getLeft());
              SpUtil.putInt(
                  getApplicationContext(),
                  ConstantValues.TOAST_ADDRESS_LOCATIONY,
                  iv_drag.getTop());
            }
          }
        });
  }