NestedScrollView & RecyclerView = scrollToPosition

其他一些动画:

https://developer.android.com/training/constraint-layout/motionlayout

https://developer.android.com/training/transitions

https://developer.android.com/reference/android/view/ViewGroup#setLayoutTransition(android.animation.LayoutTransition)

后面有空加个跟随手势移动位置的

RecyclerView scrollToPosition inside NestedScrollView

? this code not working

 if (index != -1) layoutManager?.scrollToPosition(index)

!so, scroll nested

recyclerView?.getChildAt(index)?.y?.let {
            nestedScrollingView.post {
                nestedScrollingView.fling(0)
                nestedScrollingView.smoothScrollTo(0, it as Int)
            }
        }