如何保存这种数据类型“concat Adapter()”？我用 json 尝试过 sharedPreferences 但它没有用。

我想保存一个带有不同 ViewHolders 的 RecyclerView 以在重新打开应用程序后显示，但我找不到方法。

class Mainactivity : AppCompatactivity(){
var userList: MutableList<ExampleItem> = mutableListOf()
var userList2: MutableList<ExampleItem> = mutableListOf()
var adapterLst : concatAdapter = concatAdapter()

override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_main)

    recycler_view.layoutManager=GridLayoutManager(this,2)
    recycler_view.setHasFixedSize(true)

    userList2.add(ExampleItem("cuatro","cinco"))
    userList.add(ExampleItem("cuatro","cuatro"))


    adapterLst = concatAdapter(ExampleAdapter(this,userList),typ2Adapter(this,userList2))

    recycler_view.adapter = adapterLst

    save.setOnClicklistener {

        saveData()

    }


}

private fun saveData() {
    val sharedPreferences = getSharedPreferences("shared preferences",Context.MODE_PRIVATE)
    val editor = sharedPreferences.edit()
    val gson = Gson()
    val json = gson.toJson(adapterLst)
    editor.putString("recycler list",json)
    editor.apply()
}}