android - 应用程序崩溃（未连接适配器；跳过布局）（Kotlin）

问题描述

这是我的代码，应用程序一次又一次地崩溃
package com.example.bookhub.adapter.fragment

import android.app.AlertDialog
import android.app.DownloadManager
import android.content.Context
import android.os.Bundle
import androidx.fragment.app.Fragment
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import android.view.textclassifier.TextClassification
import android.widget.Button
import android.widget.Toast
import androidx.recyclerview.widget.DividerItemDecoration
import androidx.recyclerview.widget.LinearLayoutManager
import androidx.recyclerview.widget.RecyclerView
import com.android.volley.Request
import com.android.volley.Response
import com.android.volley.toolbox.JsonObjectRequest
import com.android.volley.toolbox.Volley
import com.example.bookhub.R
import com.example.bookhub.adapter.adapter.DasboardRecyclerAdapter
import com.example.bookhub.adapter.model.Book
import com.example.bookhub.adapter.util.ConnectionManager


class dashboardFragment : Fragment() {
    lateinit var recyclerDashboard: RecyclerView
    lateinit var layoutManager: RecyclerView.LayoutManager
    lateinit var btnCheckInternet: Button


    lateinit var recyclerAdapter: DasboardRecyclerAdapter
    lateinit var bookInfoList: ArrayList<Book>
    /*  var bookInfoList = arrayListOf<Book>(
          Book("P.S. I love You", "Cecelia Ahern", "Rs. 299", "4.5", 77777,777),
          Book("The Great Gatsby", "F. Scott Fitzgerald", "Rs. 399", "4.1", R.drawable.great_gatsby),
          Book("Anna Karenina", "Leo Tolstoy", "Rs. 199", "4.3", R.drawable.anna_kare),
          Book("Madame Bovary", "Gustave Flaubert", "Rs. 500", "4.0", R.drawable.madame),
          Book("War and Peace", "Leo Tolstoy", "Rs. 249", "4.8", R.drawable.war_and_peace),
          Book("Lolita", "Vladimir Nabokov", "Rs. 349", "3.9", R.drawable.lolita),
          Book("Middlemarch", "George Eliot", "Rs. 599", "4.2", R.drawable.middlemarch),
          Book("The Adventures of Huckleberry Finn", "Mark Twain", "Rs. 699", "4.5", R.drawable.adventures_finn),
          Book("Moby-Dick", "Herman Melville", "Rs. 499", "4.5", R.drawable.moby_dick),
          Book("The Lord of the Rings", "J.R.R Tolkien", "Rs. 749", "5.0", R.drawable.lord_of_rings)
      )*/

    override fun onCreateView(
        inflater: LayoutInflater, container: ViewGroup?,
        savedInstanceState: Bundle?
    ): View? {
        // Inflate the layout for this com.example.bookhub.com.example.bookhub.adapter.adapter.fragment
        val view = inflater.inflate(R.layout.fragment_dashboard, container, false)



        recyclerDashboard = view.findViewById(R.id.recylerDashboard)



        btnCheckInternet = view.findViewById(R.id.btnCheckInternet)
        btnCheckInternet.setOnClickListener {
            if (ConnectionManager().checkConnectivity(activity as Context)) {
                //internet is available
                val dialog = AlertDialog.Builder(activity as Context)
                dialog.setTitle("Success")
                dialog.setMessage("Internet Connection Found")
                dialog.setPositiveButton("Ok") { text, listner ->

                }
                dialog.setNegativeButton("Cancel") { text, listner ->

                }

                dialog.create()
                dialog.show()

            } else {
                //internet not available
                val dialog = AlertDialog.Builder(activity as Context)
                dialog.setTitle("Error")
                dialog.setMessage("Internet Connection Not Found")
                dialog.setPositiveButton("Ok") { text, listner ->

                }
                dialog.setNegativeButton("Cancel") { text, listner ->

                }

                dialog.create()
                dialog.show()
            }
        }

        layoutManager = LinearLayoutManager(activity)


        val queue = Volley.newRequestQueue(activity as Context)

        val url = "http://13.235.250.119/v1/book/fetch_books/"

        val jsonObjectRequest =
            object : JsonObjectRequest(Request.Method.GET, url, null, Response.Listener {
                // Here we will handle the respose
                val success = it.getBoolean("success")
                if (success) {
                    val data = it.getJSONArray("data")
                    for (i in 0 until data.length()) {
                        val bookJsonObject = data.getJSONObject(i)
                        val bookObject = Book(
                            bookJsonObject.getString("book_id"),
                            bookJsonObject.getString("name"),
                            bookJsonObject.getString("author"),
                            bookJsonObject.getString("rating"),
                            bookJsonObject.getString("price"),
                            bookJsonObject.getString("image")

                        )
                        bookInfoList.add(bookObject)
                        recyclerAdapter = DasboardRecyclerAdapter(activity as Context, bookInfoList)

                        recyclerDashboard.adapter = recyclerAdapter
                        recyclerDashboard.layoutManager = layoutManager

                        recyclerDashboard.addItemDecoration(
                            DividerItemDecoration(
                                recyclerDashboard.context,
                                (layoutManager as LinearLayoutManager).orientation
                            )
                        )


                    }


                } else  {
                    Toast.makeText(activity as Context, "Some ERROR OCCURED", Toast.LENGTH_SHORT).show()
                }


            }, Response.ErrorListener {
                // here we handel the error
                println("Error is $it")

            }) {

                override fun getHeaders(): MutableMap<String, String> {
                    val headers = HashMap<String, String>()
                    headers["Content-type"] = "application/json"
                    headers["token"] = "fe******8a1ec7"
                    return headers
                }

            }

        queue.add(jsonObjectRequest)


        return view
    }


}
它在 LOGCAT 中给出错误
06-28 17:07:13.983 14675-14675/com.example.bookhub E/RecyclerView: No adapter attached; skipping layout
我已经添加了适配器，但它给出了错误，并且每次我运行它时应用程序都会崩溃
我认为错误出现在我声明bookInfoList的区域
或者也许在我创建jsonObectRequest的区域
提前致谢
标签： androidkotlinandroid-recyclerview
android - 应用程序崩溃（未连接适配器；跳过布局）（Kotlin）

问题描述

解决方案

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