获取View到顶部的高度

 tv_title.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener()
        {
            @Override
            public void onGlobalLayout()
            {
                mTitleTopAndHeight = tv_title.getTop();

                tv_title.getViewTreeObserver().removeGlobalOnLayoutListener(this);
            }
        });

或者

      tv_title.post(new Runnable()
        {
            @Override
            public void run()
            {
                mTitleTopAndHeight = tv_title.getTop();
            }
        });