如何在解决 RecyclerView 和 ViewPager 上的捕捉功能时获得即将被选中的页面

How to get soon-to-be-selected page while settling snapping feature on RecyclerView and ViewPager(如何在解决 RecyclerView 和 ViewPager 上的捕捉功能时获得即将被选中的页面)

问题描述

背景

ViewPager 在你执行一些滚动后会捕捉到一个视图，如果你使用类似这样的东西，RecyclerView 也可以:

LinearSnapHelper().attachToRecyclerView(recyclerView)

或者通过使用库来捕捉到某个边缘，如

回收站视图:

我尝试过的 POC 代码(ViewPager 和 RecyclerView):

MainActivity.kt

类 MainActivity : AppCompatActivity() {覆盖 fun onCreate(savedInstanceState: Bundle?) {super.onCreate(savedInstanceState)setContentView(R.layout.activity_main)val inflater = LayoutInflater.from(this)//viewPager 区域viewPager.adapter = 对象:RecyclerPagerAdapter() {var selectedHolder:RecyclerPagerAdapter.ViewHolder?=空覆盖乐趣 onCreateViewHolder(父:ViewGroup，viewType:Int):ViewHolder {返回对象:RecyclerPagerAdapter.ViewHolder(inflater.inflate(R.layout.cell, parent, false)) {}}覆盖有趣的 getItemCount(): Int = 100覆盖乐趣 onBindViewHolder(holder: ViewHolder, position: Int) {(holder.itemView as TextView).text = position.toString()}覆盖有趣的 setPrimaryItem(container: ViewGroup?, position: Int, obj: Any?) {super.setPrimaryItem(容器，位置，obj)//TODO 尽快获取即将被选中的页面val holder = obj 作为 RecyclerPagerAdapter.ViewHolderif (selectedHolder != null && selectedHolder != 持有人)(selectedHolder!!.itemView as TextView).text = position.toString()(holder.itemView as TextView).text = "selected:${position.toString()}"selectedHolder = 持有者}}viewPager.addOnPageChangeListener(对象:ViewPager.OnPageChangeListener {覆盖乐趣 onPageScrollStateChanged(state: Int) {当(状态){ViewPager.SCROLL_STATE_DRAGGING ->Log.d("AppLog", "onPageScrollStateChanged: SCROLL_STATE_DRAGGING")ViewPager.SCROLL_STATE_IDLE ->Log.d("AppLog", "onPageScrollStateChanged: SCROLL_STATE_IDLE")ViewPager.SCROLL_STATE_SETTLING ->Log.d("AppLog", "onPageScrollStateChanged: SCROLL_STATE_SETTLING")}}覆盖乐趣 onPageScrolled(position: Int, positionOffset: Float, positionOffsetPixels: Int) {Log.d("AppLog", "onPageScrolled: position:$position positionOffset :$positionOffset positionOffsetPixels:$positionOffsetPixels")}覆盖乐趣 onPageSelected(position: Int) {Log.d("AppLog", "onPageSelected:" + 位置)}})//recyclerView区域//不需要，因为我为此使用了一个库:LinearSnapHelper().attachToRecyclerView(recyclerView)recyclerView.setHasFixedSize(true)recyclerView.adapter = 对象:RecyclerView.Adapter() {覆盖有趣的 getItemCount(): Int = 100覆盖乐趣 onCreateViewHolder(parent: ViewGroup?, viewType: Int): RecyclerView.ViewHolder {返回对象:RecyclerView.ViewHolder(inflater.inflate(R.layout.cell, parent, false)) {}}覆盖乐趣 onBindViewHolder(holder: RecyclerView.ViewHolder, position: Int) {(holder.itemView as TextView).text = position.toString()}}recyclerView.addOnPageChangedListener { oldPosition, newPosition ->Log.d("AppLog", "OnPageChanged:$oldPosition->$newPosition") }recyclerView.addOnScrollListener(对象:RecyclerView.OnScrollListener(){@SuppressLint("ClickableViewAccessibility")覆盖乐趣 onScrollStateChanged(recyclerView: RecyclerView?, newState: Int) {super.onScrollStateChanged(recyclerView, newState)当(新状态){RecyclerView.SCROLL_STATE_IDLE ->{Log.d("AppLog", "状态:SCROLL_STATE_IDLE")recyclerViewStateTextView.text = "状态:SCROLL_STATE_IDLE"//setOnTouchListener 并不能很好地工作.它使滚动卡住//recyclerView!!.setOnTouchListener(null)}RecyclerView.SCROLL_STATE_SETTLING ->{//结算时的TODO，阻止touch，更新即将被关注的页面Log.d("AppLog", "状态:SCROLL_STATE_SETTLING")recyclerViewStateTextView.text = "状态:SCROLL_STATE_SETTLING"//recyclerView!!.setOnTouchListener(object : View.OnTouchListener {//覆盖 fun onTouch(v: View?, event: MotionEvent?): Boolean {//返回真/