Kotlin E/RecyclerView：没有连接适配器；跳过布局

Question

大家好，我的新闻应用程序有问题。我的应用程序运行良好。我可以从 fire base 获取数据，并且可以在使用调试时将它们写下来。但是，当我在虚拟设备回收器中打开应用程序时，片段中未显示视图并出现此错误：E/RecyclerView：未连接适配器；跳过布局

我的适配器代码是这样的： `class FeedAdapter(var userList :ArrayList) : RecyclerView.Adapter() {

class MyViewHolder(itemView : View): RecyclerView.ViewHolder(itemView) {
    val comment : TextView = itemView.findViewById(R.id.comment)
}
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): MyViewHolder {

    val itemView = LayoutInflater.from(parent.context).inflate(R.layout.user_item,parent,false)

    return MyViewHolder(itemView)
}

override fun onBindViewHolder(holder: MyViewHolder, position: Int) {
    holder.comment.text = userList[position].comment
}

override fun getItemCount(): Int {
   return userList.size
}

}`

我的 DashboardFragment 是这样的：

`class DashboardFragment : Fragment() {

private var postArrayList: ArrayList<Post> = arrayListOf()

private var db: FirebaseFirestore ? = null

private var recyclerView: RecyclerView? = null

private var feedAdapter: FeedAdapter? = null

override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)

    db = FirebaseFirestore.getInstance()

    feedAdapter = FeedAdapter(arrayListOf())

    recyclerView?.layoutManager =
        LinearLayoutManager(context, LinearLayoutManager.VERTICAL, false)

    recyclerView?.adapter = feedAdapter

    eventChangeListener()


}

override fun onCreateView(
    inflater: LayoutInflater, container: ViewGroup?,
    savedInstanceState: Bundle?
): View? {
    return inflater.inflate(R.layout.fragment_dashboard, container, false)
}

@SuppressLint("NotifyDataSetChanged")
private fun eventChangeListener() {

    db?.collection("Posts")?.addSnapshotListener { value, _ ->

        if (value != null) {
            if (!value.isEmpty) {
                val documents = value.documents
                for (document in documents) {
                    val comment: String = (document.get("comment") ?: "").toString()

                    val post = Post(comment)

                    Log.d("avs", post.toString())
                    postArrayList.add(post)
                }

                Log.d("avsArray", postArrayList.toString())

                feedAdapter?.userList = postArrayList

                feedAdapter?.notifyDataSetChanged()
            }
        }


    }


}

}`

我找不到解决方案

我已经尝试调试我的应用程序，我的 DashboardFragment 不会有任何问题，我可以清楚地写入数据。但是当我尝试调试我的适配器时 class 我无法从中得到任何东西

Answer 1

没有recyclerView var的设置（使用findViewById(R.id.yourOwnRecycler)或ViewBinding）
所有访问视图的代码都必须在 onViewCreated

override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
    super.onViewCreated(view, savedInstanceState)

    recyclerView = view.findViewById(R.id.yourOwnRecycler)

    recyclerView?.layoutManager =
        LinearLayoutManager(context, LinearLayoutManager.VERTICAL, false)

    recyclerView?.adapter = feedAdapter

    eventChangeListener()
}

Kotlin E/RecyclerView：没有连接适配器；跳过布局

Kotlin E/RecyclerView: No adapter attached; skipping layout

layout

android-fragments

kotlin

android-recyclerview