如何檢測到Horizo​​ntalScrollView已到達結尾

Question

我想要達到結束時，右按鈕將更改顏色，當到達開始時，左按鈕將更改顏色，所以，我想問如何檢測Horizo​​ntalScrollView已結束。

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); 
    }