android-recyclerview - lateinit 属性 recyclerViewAdapter 尚未在 com.example.recyler_view_data_binding.MainActivity.onCreate(MainActivity.kt:22) 初始化

Question

“主要活动”

正如您通过错误看到我的代码，lateint var is not initilizing 导致：kotlin.UninitializedPropertyAccessException：lateinit property recyclerViewAdapter has not been initialized at com.example.recyler_view_data_binding.MainActivity.onCreate(MainActivity.kt:22)

包 com.example.recyler_view_data_binding

import Dats_Sources.dats_source_class
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import androidx.recyclerview.widget.LinearLayoutManager
import com.example.recyler_view_data_binding.databinding.ActivityMainBinding
import javax.sql.DataSource

class MainActivity : AppCompatActivity() {
    lateinit var mainActivitybinding : ActivityMainBinding

    private lateinit var recyclerViewAdapter: Recycler_view_Adapter


    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        mainActivitybinding = ActivityMainBinding.inflate(layoutInflater)
        setContentView(mainActivitybinding.root)

        val dataset = dats_source_class.createDataSet()
        recyclerViewAdapter.submitlist(dataset)

        val recyclerview = mainActivitybinding.recyclerView
        recyclerview.adapter = Recycler_view_Adapter()
        recyclerview.layoutManager= LinearLayoutManager(this , LinearLayoutManager.VERTICAL , false)
    }
}

“适配器类”包 com.example.recyler_view_data_binding

import Models.Blog_Post
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import android.widget.ImageView
import android.widget.TextView
import android.widget.ViewAnimator
import androidx.recyclerview.widget.RecyclerView
import com.bumptech.glide.Glide
import com.bumptech.glide.request.RequestOptions
import org.w3c.dom.Text

class Recycler_view_Adapter : RecyclerView.Adapter<RecyclerView.ViewHolder>() {

    private var item : List<Blog_Post> = ArrayList()


    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): RecyclerView.ViewHolder {
       val inflater : LayoutInflater = LayoutInflater.from(parent.context)
        val view : View = inflater.inflate(R.layout.layout_blog_list_item , parent , false  )
        return viewholder(view)
    }

    override fun onBindViewHolder(holder: RecyclerView.ViewHolder, position: Int) {
        when(holder){
            is viewholder -> {
                holder.bind(item.get(position))
            }
        }
    }

    override fun getItemCount(): Int {
        return item.size
    }
fun submitlist(blogPost: List<Blog_Post>){
    item = blogPost
}
    class viewholder (val itemview : View )  : RecyclerView.ViewHolder(itemview){
        val blog_image = itemview.findViewById<ImageView>(R.id.blog_image)
        val blog_title = itemview.findViewById<TextView>(R.id.blog_title)
        val user_name = itemview.findViewById<TextView>(R.id.blog_author)

        fun bind(blogPost: Blog_Post){
            blog_title.setText(blogPost.title)
            user_name.setText(blogPost.username)

            val requestOptions = RequestOptions().placeholder(R.drawable.ic_launcher_background).error(R.drawable.ic_launcher_background)
            Glide.with(itemView.context).applyDefaultRequestOptions(requestOptions)
                .load(blogPost.image).into(blog_image)
        }

    }
}