如何检测Horizo​​ntalScrollView已到达终点

Question

我希望当到达结束时，右键会改变颜色，当到达开头时，左键会改变颜色，所以，我想问一下如何检测Horizo​​ntalScrollView已经到了结尾。

Answer 1

    maxScrollX = horizontalScrollView.getChildAt(0).getMeasuredWidth()-horizontalScrollView.getMeasuredWidth(); 
    if (horizontalScrollView.getScrollX() == 0) { 
        lImageView.setImageResource(R.drawable.left_green); 
    } else { 
        lImageView.setImageResource(R.drawable.left); 
    }

    if (horizontalScrollView.getScrollX() == maxScrollX) { 
        rImageView.setImageResource(R.drawable.right_green); 
    } else { 
        rImageView.setImageResource(R.drawable.right); 
    }