项目列表未显示在RecyclerView中

huangapple
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英文:

List of items aren't showing up in the RecyclerView

问题

以下是翻译好的内容：

我正在自学安卓应用开发（以及Java）。在弄清楚为什么我的列表项没有显示出来时遇到了麻烦。弹出窗口运行得很好，所以我没有包含它的代码。

我尝试通过添加Log.d()消息来查看GroceryItemAdapter是否正常工作，但它没有显示出来。我猜想是我制作的适配器有问题？

更新：
修复了一行代码，但现在我遇到了这个问题（稍后会更新，要研究一下是什么原因或者进行调试）：

AutoCrab的答案帮助解决了空对象问题，我还发现在将整数传递给setText()之前需要将其转换为字符串。

  1. java.lang.NullPointerException: 尝试在空对象引用上调用虚拟方法 'android.view.View android.widget.TextView.findViewById(int)'
  2.     at com.example.myapplication.GroceryListAdapter$ViewHolder.<init>
  1. package com.example.myapplication;
  3. import android.content.Context;
  4. import android.util.Log;
  5. import android.view.LayoutInflater;
  6. import android.view.View;
  7. import android.view.ViewGroup;
  8. import android.widget.TextView;
  10. import androidx.annotation.NonNull;
  11. import androidx.recyclerview.widget.RecyclerView;
  13. import java.util.ArrayList;
  14. import java.util.List;
  16. //负责将模型中的数据显示到RecyclerView中的行中
  17. public class GroceryListAdapter extends RecyclerView.Adapter<GroceryListAdapter.ViewHolder>{
  18.     private List<GroceryList> lists = new ArrayList<>();
  20.     public GroceryListAdapter(List<GroceryList> lists) {
  21.         this.lists = lists;
  22.     }
  24.     @NonNull
  25.     @Override
  26.     public ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
  27.         View groceryListView = LayoutInflater.from(parent.getContext()).inflate(R.layout.grocery_list_entry, parent, false);
  28.         Log.d("MEJD", "我在这里吗？");
  29.         ViewHolder viewHolder = new ViewHolder(groceryListView);
  30.         return viewHolder;
  31.     }
  33.     @Override
  34.     public void onBindViewHolder(@NonNull ViewHolder holder, int position) {
  35.         GroceryList groceryListItem = lists.get(position);
  37.         TextView textView = holder.listTitle;
  38.         textView.setText(groceryListItem.getListName());
  39.         Log.d("MEJD", "我在这里");
  40.         TextView numItemsView = holder.numItems;
  41.         numItemsView.setText(String.valueOf(groceryListItem.getNumItems()));
  42.     }
  44.     @Override
  45.     public int getItemCount() {
  46.         return lists.size();
  47.     }
  49.     class ViewHolder extends RecyclerView.ViewHolder {
  50.         public TextView listTitle;
  51.         public TextView numItems;
  53.         public ViewHolder(@NonNull View itemView) {
  54.             super(itemView);
  55.             listTitle = itemView.findViewById(R.id.groceryListName);
  56.             numItems = itemView.findViewById(R.id.numItemsList);
  57.         }
  58.     }
  59. }

GroceryList类：

  1. package com.example.myapplication;
  3. import java.util.List;
  5. public class GroceryList {
  6.     private String listName;
  7.     private int numItems;
  9.     public GroceryList(String listName, int numItems) {
  10.         this.listName = listName;
  11.         this.numItems = numItems;
  12.     }
  14.     public String getListName() {
  15.         return listName;
  16.     }
  18.     public void setListName(String listName) {
  19.         this.listName = listName;
  20.     }
  22.     public int getNumItems() {
  23.         return numItems;
  24.     }
  26.     public void setNumItems(int numItems) {
  27.         this.numItems = numItems;
  28.     }
  29. }

GroceryListAdapter适配器：

  1. import android.content.Context;
  2. import android.util.Log;
  3. import android.view.LayoutInflater;
  4. import android.view.View;
  5. import android.view.ViewGroup;
  6. import android.widget.TextView;
  8. import androidx.annotation.NonNull;
  9. import androidx.recyclerview.widget.RecyclerView;
  11. import java.util.ArrayList;
  12. import java.util.List;
  14. public class GroceryListAdapter extends RecyclerView.Adapter<GroceryListAdapter.ViewHolder> {
  15.     private List<GroceryList> lists = new ArrayList<>();
  17.     public GroceryListAdapter(List<GroceryList> lists) {
  18.         this.lists = lists;
  19.     }
  21.     @NonNull
  22.     @Override
  23.     public ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
  24.         View groceryListView = LayoutInflater.from(parent.getContext()).inflate(R.layout.grocery_list_entry, parent, false);
  25.         Log.d("MEJD", "我在这里吗？");
  26.         ViewHolder viewHolder = new ViewHolder(groceryListView);
  27.         return viewHolder;
  28.     }
  30.     @Override
  31.     public void onBindViewHolder(@NonNull ViewHolder holder, int position) {
  32.         GroceryList groceryListItem = lists.get(position);
  34.         TextView textView = holder.listTitle;
  35.         textView.setText(groceryListItem.getListName());
  36.         Log.d("MEJD", "我在这里");
  37.         TextView numItemsView = holder.numItems;
  38.         numItemsView.setText(String.valueOf(groceryListItem.getNumItems()));
  39.     }
  41.     @Override
  42.     public int getItemCount() {
  43.         return lists.size();
  44.     }
  46.     class ViewHolder extends RecyclerView.ViewHolder {
  47.         public TextView listTitle;
  48.         public TextView numItems;
  50.         public ViewHolder(@NonNull View itemView) {
  51.             super(itemView);
  52.             listTitle = itemView.findViewById(R.id.groceryListName);
  53.             numItems = itemView.findViewById(R.id.numItemsList);
  54.         }
  55.     }
  56. }

MainActivity的XML文件：

  1. <?xml version="1.0" encoding="utf-8"?>
  2. <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
  3.     xmlns:app="http://schemas.android.com/apk/res-auto"
  4.     xmlns:tools="http://schemas.android.com/tools"
  5.     android:layout_width="match_parent"
  6.     android:layout_height="match_parent"
  7.     tools:context=".MainActivity">
  9.     <androidx.appcompat.widget.Toolbar
  10.         android:id="@+id/homeToolbar"
  11.         android:layout_width="match_parent"
  12.         android:layout_height="wrap_content"
  13.         android:background="#27D3C2"
  14.         android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar"
  15.         app:layout_constraintTop_toTopOf="parent"
  16.         app:title="Add Grocery List"
  17.         app:titleMarginStart="130dp" />
  19.     <ImageButton
  20.         android:id="@+id/addButton"
  21.         android:layout_width="61dp"
  22.         android:layout_height="56dp"
  23.         android:layout_alignBottom="@+id/homeToolbar"
  24.         android:layout_alignParentStart="true"
  25.         android:layout_alignParentTop="true"
  26.         android:layout_alignParentEnd="true"
  27.         android:layout_marginStart="322dp"
  28.         android:layout_marginTop="0dp"
  29.         android:layout_marginEnd="29dp"
  30.         android:layout_marginBottom="0dp"
  31.         android:backgroundTint="#00FFFFFF"
  32.         android:clickable="true"
  33.         android:contentDescription="@+string/add list button"
  34.         app:layout_constraintEnd_toEndOf="@+id/homeToolbar"
  35.         app:layout_constraintHorizontal_bias="1.0"
  36.         app:layout_constraintStart_toStartOf="@+id/homeToolbar"
  37.         app:layout_constraintTop_toTopOf="@+id/homeToolbar"
  38.         app:srcCompat="@drawable/add_icon"
  39.         android:focusable="true" />
  41.     <android
  43. <details>
  44. <summary>英文:</summary>
  46. I am teaching myself android app development(and Java). Having trouble figuring out why the items of my list are not showing up. The pop up works fine, so I didn&#39;t include the code for it. 
  48. I tried to see if the `GroceryItemAdapter` is working by adding a `Log.d()` message and it doesn&#39;t show up. I&#39;m guessing it&#39;s the Adapter I made?
  50. **Update:**
  51. Fixed a line, but now I&#39;m getting this(will update this later, going to research what&#39;s the cause or debug it):
  53. AutoCrab&#39;s answer helped solve the null object issue, I also figured out I needed to convert my integer into a string before passing it to `setText()`. 
  55.     java.lang.NullPointerException: Attempt to invoke virtual method &#39;android.view.View android.widget.TextView.findViewById(int)&#39; on a null object reference
  56.             at com.example.myapplication.GroceryListAdapter$ViewHolder.&lt;init&gt;
  60.     
  61.     package com.example.myapplication;
  62.     
  63.     import android.content.Context;
  64.     import android.util.Log;
  65.     import android.view.LayoutInflater;
  66.     import android.view.View;
  67.     import android.view.ViewGroup;
  68.     import android.widget.TextView;
  69.     
  70.     import androidx.annotation.NonNull;
  71.     import androidx.recyclerview.widget.RecyclerView;
  72.     
  73.     import java.util.ArrayList;
  74.     import java.util.List;
  75.     
  76.     //responsible for displaying data from the model into a row in the recycler view
  77.     public class GroceryListAdapter extends RecyclerView.Adapter&lt;GroceryListAdapter.ViewHolder&gt;{
  78.         private List&lt;GroceryList&gt; lists = new ArrayList&lt;&gt;();
  79.         public GroceryListAdapter(List&lt;GroceryList&gt; lists) {
  80.             this.lists = lists;
  81.         }
  82.         
  83.    
  84.         //onCreateViewHolder is responsible for creating each view
  85.         @NonNull
  86.         @Override
  87.         public ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
  88.             //create a new view and wrap it inside a new viewholder
  89.             //use layout inflator to inflate a view
  90.             View groceryListView = LayoutInflater.from(parent.getContext()).inflate(R.layout.grocery_list_entry,parent,false);
  91.             Log.d(&quot;MEJD&quot;, &quot;Iamhere?&quot;);
  92.             //wrap it inside a ViewHolder and return it
  93.             ViewHolder viewHolder = new ViewHolder(groceryListView);
  94.             return viewHolder;
  95.         }
  96.     
  97.         //onBindViewHolder is responsible for taking data at a particular position and
  98.         //putting it into a viewholder
  99.         @Override
  100.         public void onBindViewHolder(@NonNull ViewHolder holder, int position) {
  101.             //get data model by position
  102.             GroceryList groceryListItem = lists.get(position);
  103.     
  104.             //set the item views based on the data models
  105.             TextView textView = holder.listTitle;
  106.             textView.setText(groceryListItem.getListName());
  107.             Log.d(&quot;MEJD&quot;, &quot;Iamhere&quot;);
  108.             TextView numItemsView = holder.numItems;
  109.             numItemsView.setText(groceryListItem.getNumItems());
  110.     
  111.        }
  112.     
  113.         //get number of items in the data
  114.         @Override
  115.         public int getItemCount() {
  116.             lists.size();
  117.         }
  118.     
  119.         class ViewHolder extends RecyclerView.ViewHolder{
  120.             //member variables
  121.             public TextView listTitle;
  122.             public TextView numItems;
  123.             public ViewHolder(@NonNull View itemView) {
  124.                 super(itemView);
  125.     
  126.                 listTitle.findViewById(R.id.groceryListName);
  127.                 numItems.findViewById(R.id.numItemsList);
  128.             }
  129.         }
  130.     }
  132. GroceryList Class: 
  134.         package com.example.myapplication;
  135.         
  136.         import java.util.List;
  137.         
  138.         public class GroceryList {
  139.             //class to hold the info of each list item
  140.            private String listName;
  141.            private int numItems;
  142.            //will need to refactor later.....
  143.         
  144.             public GroceryList(String listName, int numItems) {
  145.                 this.listName = listName;
  146.                 this.numItems = numItems;
  147.         
  148.             }
  149.             public String getListName() {
  150.                 return listName;
  151.             }
  152.         
  153.             public void setListName(String listName) {
  154.                 this.listName = listName;
  155.             }
  156.         
  157.             public int getNumItems() {
  158.                 return numItems;
  159.             }
  160.         
  161.             public void setNumItems(int numItems) {
  162.                 this.numItems = numItems;
  163.             }
  164.         
  165.         
  166.         }
  167.     
  168. GroceryList Adapter: 
  170.     
  171.     import android.content.Context;
  172.     import android.util.Log;
  173.     import android.view.LayoutInflater;
  174.     import android.view.View;
  175.     import android.view.ViewGroup;
  176.     import android.widget.TextView;
  177.     
  178.     import androidx.annotation.NonNull;
  179.     import androidx.recyclerview.widget.RecyclerView;
  180.     
  181.     import java.util.ArrayList;
  182.     import java.util.List;
  183.     
  184.     //responsible for displaying data from the model into a row in the recycler view
  185.     public class GroceryListAdapter extends RecyclerView.Adapter&lt;GroceryListAdapter.ViewHolder&gt;{
  186.         private List&lt;GroceryList&gt; lists = new ArrayList&lt;&gt;();
  187.         public GroceryListAdapter(List&lt;GroceryList&gt; lists) {
  188.             this.lists = lists;
  189.         }
  190.         //create a constructor
  191.     
  192.     
  193.         //onCreateViewHolder is responsible for creating each view
  194.         @NonNull
  195.         @Override
  196.         public ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
  197.             //create a new view and wrap it inside a new viewholder
  198.             //use layout inflator to inflate a view
  199.             View groceryListView = LayoutInflater.from(parent.getContext()).inflate(R.layout.grocery_list_entry,parent,false);
  200.             Log.d(&quot;MEJD&quot;, &quot;Iamhere?&quot;);
  201.             //wrap it inside a ViewHolder and return it
  202.             ViewHolder viewHolder = new ViewHolder(groceryListView);
  203.             return viewHolder;
  204.         }
  205.     
  206.         //onBindViewHolder is responsible for taking data at a particular position and
  207.         //putting it into a viewholder
  208.         @Override
  209.         public void onBindViewHolder(@NonNull ViewHolder holder, int position) {
  210.             //get data model by position
  211.             GroceryList groceryListItem = lists.get(position);
  212.     
  213.             //set the item views based on the data models
  214.             TextView textView = holder.listTitle;
  215.             textView.setText(groceryListItem.getListName());
  216.             Log.d(&quot;MEJD&quot;, &quot;Iamhere&quot;);
  217.             TextView numItemsView = holder.numItems;
  218.             numItemsView.setText(groceryListItem.getNumItems());
  219.     
  220.        }
  221.     
  222.         //get number of items in the data
  223.         @Override
  224.         public int getItemCount() {
  225.             return 0;
  226.         }
  227.     
  228.         class ViewHolder extends RecyclerView.ViewHolder{
  229.             //member variables
  230.             public TextView listTitle;
  231.             public TextView numItems;
  232.             public ViewHolder(@NonNull View itemView) {
  233.                 super(itemView);
  234.     
  235.                 listTitle.findViewById(R.id.groceryListName);
  236.                 numItems.findViewById(R.id.numItemsList);
  237.             }
  238.         }
  239.     }
  242. XML file for MainActivity: 
  244.     &lt;?xml version=&quot;1.0&quot; encoding=&quot;utf-8&quot;?&gt;
  245.     &lt;RelativeLayout xmlns:android=&quot;http://schemas.android.com/apk/res/android&quot;
  246.         xmlns:app=&quot;http://schemas.android.com/apk/res-auto&quot;
  247.         xmlns:tools=&quot;http://schemas.android.com/tools&quot;
  248.         android:layout_width=&quot;match_parent&quot;
  249.         android:layout_height=&quot;match_parent&quot;
  250.         tools:context=&quot;.MainActivity&quot;&gt;
  251.     
  252.         &lt;androidx.appcompat.widget.Toolbar
  253.             android:id=&quot;@+id/homeToolbar&quot;
  254.             android:layout_width=&quot;match_parent&quot;
  255.             android:layout_height=&quot;wrap_content&quot;
  256.             android:background=&quot;#27D3C2&quot;
  257.             android:theme=&quot;@style/ThemeOverlay.AppCompat.Dark.ActionBar&quot;
  258.             app:layout_constraintTop_toTopOf=&quot;parent&quot;
  259.             app:title=&quot;Add Grocery List&quot;
  260.             app:titleMarginStart=&quot;130dp&quot; /&gt;
  261.     
  262.         &lt;ImageButton
  263.             android:id=&quot;@+id/addButton&quot;
  264.             android:layout_width=&quot;61dp&quot;
  265.             android:layout_height=&quot;56dp&quot;
  266.             android:layout_alignBottom=&quot;@+id/homeToolbar&quot;
  267.             android:layout_alignParentStart=&quot;true&quot;
  268.             android:layout_alignParentTop=&quot;true&quot;
  269.             android:layout_alignParentEnd=&quot;true&quot;
  270.             android:layout_marginStart=&quot;322dp&quot;
  271.             android:layout_marginTop=&quot;0dp&quot;
  272.             android:layout_marginEnd=&quot;29dp&quot;
  273.             android:layout_marginBottom=&quot;0dp&quot;
  274.             android:backgroundTint=&quot;#00FFFFFF&quot;
  275.             android:clickable=&quot;true&quot;
  276.             android:contentDescription=&quot;@+string/add list button&quot;
  277.             app:layout_constraintEnd_toEndOf=&quot;@+id/homeToolbar&quot;
  278.             app:layout_constraintHorizontal_bias=&quot;1.0&quot;
  279.             app:layout_constraintStart_toStartOf=&quot;@+id/homeToolbar&quot;
  280.             app:layout_constraintTop_toTopOf=&quot;@+id/homeToolbar&quot;
  281.             app:srcCompat=&quot;@drawable/add_icon&quot;
  282.             android:focusable=&quot;true&quot; /&gt;
  283.     
  284.         &lt;androidx.recyclerview.widget.RecyclerView
  285.             android:id=&quot;@+id/rvView&quot;
  286.             android:layout_width=&quot;match_parent&quot;
  287.             android:layout_height=&quot;match_parent&quot;
  288.             android:layout_below=&quot;@+id/homeToolbar&quot;
  289.             android:layout_alignParentStart=&quot;true&quot;
  290.             android:layout_alignParentEnd=&quot;true&quot;
  291.             android:layout_alignParentBottom=&quot;true&quot;
  292.             android:layout_marginStart=&quot;0dp&quot;
  293.             android:layout_marginTop=&quot;0dp&quot;
  294.             android:layout_marginEnd=&quot;0dp&quot;
  295.             android:layout_marginBottom=&quot;1dp&quot; /&gt;
  296.     &lt;/RelativeLayout&gt;
  299. XML for the listItem I want to use:
  301.     &lt;?xml version=&quot;1.0&quot; encoding=&quot;utf-8&quot;?&gt;
  302.     &lt;androidx.constraintlayout.widget.ConstraintLayout xmlns:android=&quot;http://schemas.android.com/apk/res/android&quot;
  303.         xmlns:app=&quot;http://schemas.android.com/apk/res-auto&quot;
  304.         xmlns:tools=&quot;http://schemas.android.com/tools&quot;
  305.         android:id=&quot;@+id/relativeLayout&quot;
  306.         android:layout_width=&quot;match_parent&quot;
  307.         android:layout_height=&quot;wrap_content&quot;&gt;
  309.     &lt;androidx.constraintlayout.widget.Guideline
  310.         android:id=&quot;@+id/guideline2&quot;
  311.         android:layout_width=&quot;wrap_content&quot;
  312.         android:layout_height=&quot;wrap_content&quot;
  313.         android:orientation=&quot;vertical&quot;
  314.         app:layout_constraintGuide_begin=&quot;15dp&quot;
  315.         app:layout_constraintStart_toStartOf=&quot;parent&quot;
  316.         app:layout_constraintTop_toTopOf=&quot;parent&quot; /&gt;
  318.     &lt;androidx.constraintlayout.widget.Guideline
  319.         android:id=&quot;@+id/guideline4&quot;
  320.         android:layout_width=&quot;wrap_content&quot;
  321.         android:layout_height=&quot;wrap_content&quot;
  322.         android:orientation=&quot;vertical&quot;
  323.         app:layout_constraintGuide_begin=&quot;35dp&quot;
  324.         app:layout_constraintStart_toStartOf=&quot;parent&quot;
  325.         app:layout_constraintTop_toTopOf=&quot;parent&quot; /&gt;
  327.     &lt;TextView
  328.         android:id=&quot;@+id/numItemsList&quot;
  329.         android:layout_width=&quot;28dp&quot;
  330.         android:layout_height=&quot;23dp&quot;
  331.         android:layout_marginEnd=&quot;34dp&quot;
  332.         android:paddingTop=&quot;0dp&quot;
  333.         android:paddingBottom=&quot;0dp&quot;
  334.         android:text=&quot;@string/numberItems&quot;
  335.         android:textSize=&quot;12sp&quot;
  336.         app:layout_constraintBottom_toBottomOf=&quot;parent&quot;
  337.         app:layout_constraintEnd_toEndOf=&quot;parent&quot;
  338.         app:layout_constraintHorizontal_bias=&quot;1.0&quot;
  339.         app:layout_constraintStart_toStartOf=&quot;parent&quot;
  340.         app:layout_constraintTop_toTopOf=&quot;parent&quot;
  341.         app:layout_constraintVertical_bias=&quot;0.0&quot; /&gt;
  343.     &lt;androidx.constraintlayout.widget.Guideline
  344.         android:id=&quot;@+id/guideline5&quot;
  345.         android:layout_width=&quot;wrap_content&quot;
  346.         android:layout_height=&quot;wrap_content&quot;
  347.         android:orientation=&quot;vertical&quot;
  348.         app:layout_constraintGuide_end=&quot;15dp&quot; /&gt;
  350.     &lt;androidx.constraintlayout.widget.Guideline
  351.         android:id=&quot;@+id/guideline6&quot;
  352.         android:layout_width=&quot;wrap_content&quot;
  353.         android:layout_height=&quot;wrap_content&quot;
  354.         android:orientation=&quot;vertical&quot;
  355.         app:layout_constraintGuide_end=&quot;35dp&quot; /&gt;
  357.     &lt;TextView
  358.         android:id=&quot;@+id/groceryListName&quot;
  359.         android:layout_width=&quot;270dp&quot;
  360.         android:layout_height=&quot;22dp&quot;
  361.         android:layout_marginStart=&quot;35dp&quot;
  362.         android:layout_marginEnd=&quot;44dp&quot;
  363.         android:text=&quot;@string/groceryListName&quot;
  364.         app:layout_constraintBottom_toBottomOf=&quot;parent&quot;
  365.         app:layout_constraintEnd_toStartOf=&quot;@+id/numItemsList&quot;
  366.         app:layout_constraintHorizontal_bias=&quot;1.0&quot;
  367.         app:layout_constraintStart_toStartOf=&quot;parent&quot;
  368.         app:layout_constraintTop_toTopOf=&quot;parent&quot; /&gt;
  369.     &lt;/androidx.constraintlayout.widget.ConstraintLayout&gt;
  376. </details>
  379. # 答案1
  380. **得分**: 0
  382. 也许是这样的：
  384. ```java
  385.     // 获取数据中的项目数量
  386.     @Override
  387.     public int getItemCount() {
  388.         return 0;
  389.     }

编辑

  1.     // 获取数据中的项目数量
  2.     @Override
  3.     public int getItemCount() {
  4.         return lists.size();
  5.     }
英文:

Maybe this:

  1. //get number of items in the data
  2. @Override
  3. public int getItemCount() {
  4. return 0;
  5. }

edit

  1. //get number of items in the data
  2. @Override
  3. public int getItemCount() {
  4. return lists.size();
  5. }

答案2

得分: 0

Add itemCount

  1. //
  2. @Override
  3. public int getItemCount() {
  4. return lists.size();
  5. }

Change ViewHolder class

  1. class ViewHolder extends RecyclerView.ViewHolder{
  2. //member variables
  3. public TextView listTitle;
  4. public TextView numItems;
  5. public ViewHolder(@NonNull View itemView) {
  6. super(itemView);
  7. listTitle = itemView.findViewById(R.id.groceryListName);
  8. numItems = itemView.findViewById(R.id.numItemsList);
  9. }
  10. }
英文:

Add itemCount

  1. //
  2. @Override
  3. public int getItemCount() {
  4. return lists.size();
  5. }

Change ViewHolder class

  1. class ViewHolder extends RecyclerView.ViewHolder{
  2. //member variables
  3. public TextView listTitle;
  4. public TextView numItems;
  5. public ViewHolder(@NonNull View itemView) {
  6. super(itemView);
  7. listTitle = itemView.findViewById(R.id.groceryListName);
  8. numItems = itemView.findViewById(R.id.numItemsList);
  9. }
  10. }

huangapple
  • 本文由 发表于 2020年9月16日 09:50:48
  • 转载请务必保留本文链接：https://go.coder-hub.com/63912023.html
  • android
  • android-recyclerview
  • java
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