Android中ScrollTo与ScrollBy的区别

Android中ScrollTo与ScrollBy的区别

经过查看源码，ScrollBy方法中通过调用ScrollTo实现
ScrollTo每次都回到原点然后进行移动
ScrollBy是在上一次移动的距离基础上进行移动

    var mDownY = 0f;
    var mMoveY = 0;
    override fun onTouchEvent(event: MotionEvent?): Boolean {
        when (event?.action) {
            MotionEvent.ACTION_DOWN -> {
                mDownX = event.x
                mDownY = event.y
            }
            MotionEvent.ACTION_MOVE -> {
//                scrollBy(0, (mDownY - event.y).toInt())
                scrollTo(0, mMoveY + (mDownY - event.y).toInt())
                mMoveY = scrollY
            }
        }

        return true
    }