获取列表在fastadapter中的保存状态

Question

我在我的应用程序中使用了 fastadapter。从另一个屏幕返回时如何获取列表的保存状态。

我使用了 fastadapter 库中的现成方法，但由于某些原因它不起作用。

class ViewHolder(itemView: View) : FastAdapter.ViewHolder<ProgramsGalleryItem>(itemView) {

        val rootVg = itemView.findViewById<ViewGroup>(R.id.root_vg)
        val rv = itemView.findViewById<RecyclerView>(R.id.recycler_rv)
        val titleTv = itemView.findViewById<TextView>(R.id.title_tv)

        val layoutManager = LinearLayoutManager(rv.context, LinearLayoutManager.VERTICAL, false)
        private val KEY_FASTADAPTER_STATE = "fastAdapter_state"
        var mFastAdapterState = Bundle()

        override fun bindView(item: ProgramsGalleryItem, payloads: MutableList<Any>) {

            if (item.fastAdapter.itemCount == 0) {
               rv.itemAnimator = null
               if(item.isVertical) {

                   val lp = rv.layoutParams as LinearLayout.LayoutParams
                   lp.setMargins(lp.leftMargin, 0, lp.rightMargin, lp.bottomMargin)
                   rv.setPadding(0)
                   rv.layoutManager = layoutManager
                   rv.layoutParams = lp
               }
                val layoutId = if(item.isVertical){R.layout.item_common_program}else{R.layout.item_common_program_short}
                val items = item.list.map { it.item(layoutId) }
                val adapter = ItemAdapter<ProgramItem>()
                adapter.add(items)
                item.fastAdapter.addAdapter(0, adapter)
                rv.adapter = item.fastAdapter
                item.fastAdapter.withSavedInstanceState(mFastAdapterState, KEY_FASTADAPTER_STATE)
                titleTv.text = item.title
            }
        }

        override fun unbindView(item: ProgramsGalleryItem) {
            rv.adapter = null
            titleTv.text = null

            item.fastAdapter.saveInstanceState(mFastAdapterState!!, KEY_FASTADAPTER_STATE)
            item.fastAdapter = BindableFastAdapter()

        }
    }
}