为什么我的适配器不工作？如何解决NullPointerException错误？

Question

我正在构建新闻应用程序。我收到Kotlin空指针异常错误。我已经单击了频道名称列表，它将显示与那些频道来源不同的新闻，但是当我单击其中一个新闻频道时，它崩溃了。谁能帮我提供我的代码？这是它显示的错误：

FATAL EXCEPTION: main
    Process: com.example.newswrld, PID: 16135
    kotlin.KotlinNullPointerException
        at com.example.newswrld.Adapter.ViewHolder.ListNewsAdapter.onBindViewHolder(ListNewsAdapter.kt:47)
        at com.example.newswrld.Adapter.ViewHolder.ListNewsAdapter.onBindViewHolder(ListNewsAdapter.kt:16)
        at androidx.recyclerview.widget.RecyclerView$Adapter.onBindViewHolder(RecyclerView.java:7065)
        at androidx.recyclerview.widget.RecyclerView$Adapter.bindViewHolder(RecyclerView.java:7107)
        at androidx.recyclerview.widget.RecyclerView$Recycler.tryBindViewHolderByDeadline(RecyclerView.java:6012)
        at androidx.recyclerview.widget.RecyclerView$Recycler.tryGetViewHolderForPositionByDeadline(RecyclerView.java:6279)
        at androidx.recyclerview.widget.RecyclerView$Recycler.getViewForPosition(RecyclerView.java:6118)
        at androidx.recyclerview.widget.RecyclerView$Recycler.getViewForPosition(RecyclerView.java:6114)
        at androidx.recyclerview.widget.LinearLayoutManager$LayoutState.next(LinearLayoutManager.java:2303)
        at androidx.recyclerview.widget.LinearLayoutManager.layoutChunk(LinearLayoutManager.java:1627)
        at androidx.recyclerview.widget.LinearLayoutManager.fill(LinearLayoutManager.java:1587)
        at androidx.recyclerview.widget.LinearLayoutManager.onLayoutChildren(LinearLayoutManager.java:665)
        at androidx.recyclerview.widget.RecyclerView.dispatchLayoutStep2(RecyclerView.java:4134)
        at androidx.recyclerview.widget.RecyclerView.dispatchLayout(RecyclerView.java:3851)
        at androidx.recyclerview.widget.RecyclerView.onLayout(RecyclerView.java:4404)
        at android.view.View.layout(View.java:20672)
        at android.view.ViewGroup.layout(ViewGroup.java:6194)
        at android.widget.RelativeLayout.onLayout(RelativeLayout.java:1083)
        at android.view.View.layout(View.java:20672)
        at android.view.ViewGroup.layout(ViewGroup.java:6194)
        at androidx.swiperefreshlayout.widget.SwipeRefreshLayout.onLayout(SwipeRefreshLayout.java:625)
        at android.view.View.layout(View.java:20672)
        at android.view.ViewGroup.layout(ViewGroup.java:6194)
        at android.widget.FrameLayout.layoutChildren(FrameLayout.java:323)
        at android.widget.FrameLayout.onLayout(FrameLayout.java:261)
        at android.view.View.layout(View.java:20672)
        at android.view.ViewGroup.layout(ViewGroup.java:6194)
        at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1812)
        at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1656)
        at android.widget.LinearLayout.onLayout(LinearLayout.java:1565)
        at android.view.View.layout(View.java:20672)
        at android.view.ViewGroup.layout(ViewGroup.java:6194)
        at android.widget.FrameLayout.layoutChildren(FrameLayout.java:323)
        at android.widget.FrameLayout.onLayout(FrameLayout.java:261)
        at android.view.View.layout(View.java:20672)
        at android.view.ViewGroup.layout(ViewGroup.java:6194)
        at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1812)
        at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1656)
        at android.widget.LinearLayout.onLayout(LinearLayout.java:1565)
        at android.view.View.layout(View.java:20672)
        at android.view.ViewGroup.layout(ViewGroup.java:6194)
        at android.widget.FrameLayout.layoutChildren(FrameLayout.java:323)
        at android.widget.FrameLayout.onLayout(FrameLayout.java:261)
        at com.android.internal.policy.DecorView.onLayout(DecorView.java:753)
        at android.view.View.layout(View.java:20672)
        at android.view.ViewGroup.layout(ViewGroup.java:6194)
        at android.view.ViewRootImpl.performLayout(ViewRootImpl.java:2792)
        at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:2319)
        at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1460)
        at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:7183)
        at android.view.Choreographer$CallbackRecord.run(Choreographer.java:949)
        at android.view.Choreographer.doCallbacks(Choreographer.java:761)
        at android.view.Choreographer.doFrame(Choreographer.java:696)
        at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:935)
        at android.os.Handler.handleCallback(Handler.java:873)
2020-06-05 18:05:23.297 16135-16135/com.example.newswrld E/AndroidRuntime:     at android.os.Handler.dispatchMessage(Handler.java:99)
        at android.os.Looper.loop(Looper.java:193)
        at android.app.ActivityThread.main(ActivityThread.java:6669)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)

这是ListNewsAdapter.kt：

package com.example.newswrld.Adapter.ViewHolder

import android.content.Context
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import androidx.recyclerview.widget.RecyclerView
import com.example.newswrld.Common.ISO8601Parser
import com.example.newswrld.Interface.ItemClickListener
import com.example.newswrld.Model.Article
import com.example.newswrld.R
import com.squareup.picasso.Picasso
import java.text.ParseException
import java.util.*

class ListNewsAdapter(val articleList:MutableList<Article>, private val context: Context):RecyclerView.Adapter<ListNewsViewHolder>()

    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ListNewsViewHolder 
        val inflater=LayoutInflater.from(parent!!.context)
        val itemView=inflater.inflate(R.layout.news_layout,parent,false)
        return ListNewsViewHolder(itemView)
    

    override fun getItemCount(): Int 
        return articleList.size
    

    override fun onBindViewHolder(holder: ListNewsViewHolder, position: Int) 
        Picasso.with(context)
            .load(articleList[position].urlToImage)
            .into(holder.article_image)

        if(articleList[position].title!!.length > 65)
            holder.article_title.text=articleList[position].title!!.substring(0,65)+"..."
        
        else
            holder.article_title.text=articleList[position].title!!
        
        if(articleList[position].publishedAt!=null)
            var date: Date?=null
            try 
                date=ISO8601Parser.parse(articleList[position].publishedAt!!)
            catch (ex:ParseException)
            
                ex.printStackTrace()
            
            holder.article_time.setReferenceTime(date!!.time)
        

        holder.setItemClickListener(object :ItemClickListener
            override fun onClick(view: View, position: Int) 

            
        )

这里是到源代码的链接：https://github.com/xSankeTx/NewsWRLD