简单的Android RecyclerView示例

Question

我曾经多次使用 Android 的 RecyclerView 列表控件，但这是一个相当复杂的过程。浏览一些在线教程（比如 这个，这个，以及这个），可以解决我的问题，但我想要一个最简单的示例代码，让我能够快速上手并复制粘贴。仅需要包含以下功能：

• 垂直布局
• 每行只有一个 TextView
• 响应点击事件

由于我已经多次希望有这样的代码，我最终决定为我自己和各位提供下文中的答案。

- Suragch

---

请查看此教程和源代码。 - Navneet Krishna

给未来的朋友们，这里我写了一篇详细的文章，并配有视频教程。 https://handyopinion.com/how-to-show-vertical-list-in-kotlin-using-recyclerview-example/ - Asad Ali Choudhry

你可以查看这个视频教程，它详细讲解了RecyclerView。 - Chandu

请查看此处Gist.. https://github.com/AtifAbbAsi19/-RecyclerView - Atif AbbAsi

Answer 1

下面是一个最小的示例，它将看起来像以下图片。 从空活动开始。 您将执行以下任务以添加RecyclerView。 您需要做的就是复制并粘贴每个部分中的代码。 稍后您可以自定义它以适应您的需要。

- 添加gradle依赖项 - 为活动和RecyclerView行添加xml布局文件 - 制作RecyclerView适配器 - 在您的活动中初始化RecyclerView

更新Gradle依赖项

确保以下依赖关系在您的应用程序gradle.build文件中：

implementation 'com.android.support:appcompat-v7:28.0.0'
implementation 'com.android.support:recyclerview-v7:28.0.0'

你可以更新版本号为最新的版本号。如果你仍在使用Android Studio 2.x，请使用compile而不是implementation。

创建活动布局

将RecyclerView添加到您的xml布局中。

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <android.support.v7.widget.RecyclerView
        android:id="@+id/rvAnimals"
        android:layout_width="match_parent"
        android:layout_height="match_parent"/>

</RelativeLayout>

创建行布局

在我们的RecyclerView中，每一行只会有一个TextView。创建一个新的布局资源文件。

recyclerview_row.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="horizontal"
    android:padding="10dp">

    <TextView
        android:id="@+id/tvAnimalName"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textSize="20sp"/>

</LinearLayout>

创建适配器

RecyclerView需要一个适配器来将数据填充到每一行的视图中。创建一个新的Java文件。

MyRecyclerViewAdapter.java

public class MyRecyclerViewAdapter extends RecyclerView.Adapter<MyRecyclerViewAdapter.ViewHolder> {

    private List<String> mData;
    private LayoutInflater mInflater;
    private ItemClickListener mClickListener;

    // data is passed into the constructor
    MyRecyclerViewAdapter(Context context, List<String> data) {
        this.mInflater = LayoutInflater.from(context);
        this.mData = data;
    }

    // inflates the row layout from xml when needed
    @Override
    public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View view = mInflater.inflate(R.layout.recyclerview_row, parent, false);
        return new ViewHolder(view);
    }

    // binds the data to the TextView in each row
    @Override
    public void onBindViewHolder(ViewHolder holder, int position) {
        String animal = mData.get(position);
        holder.myTextView.setText(animal);
    }

    // total number of rows
    @Override
    public int getItemCount() {
        return mData.size();
    }


    // stores and recycles views as they are scrolled off screen
    public class ViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
        TextView myTextView;

        ViewHolder(View itemView) {
            super(itemView);
            myTextView = itemView.findViewById(R.id.tvAnimalName);
            itemView.setOnClickListener(this);
        }

        @Override
        public void onClick(View view) {
            if (mClickListener != null) mClickListener.onItemClick(view, getAdapterPosition());
        }
    }

    // convenience method for getting data at click position
    String getItem(int id) {
        return mData.get(id);
    }

    // allows clicks events to be caught
    void setClickListener(ItemClickListener itemClickListener) {
        this.mClickListener = itemClickListener;
    }

    // parent activity will implement this method to respond to click events
    public interface ItemClickListener {
        void onItemClick(View view, int position);
    }
}

注释：

• 虽然不是强制要求，但我包括了对行点击事件的监听功能。这在旧版 ListViews 中可用，并且是一个常见需求。如果您不需要它，可以删除此代码。

在活动中初始化 RecyclerView

将以下代码添加到您的主活动中。

MainActivity.java

public class MainActivity extends AppCompatActivity implements MyRecyclerViewAdapter.ItemClickListener {

    MyRecyclerViewAdapter adapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        // data to populate the RecyclerView with
        ArrayList<String> animalNames = new ArrayList<>();
        animalNames.add("Horse");
        animalNames.add("Cow");
        animalNames.add("Camel");
        animalNames.add("Sheep");
        animalNames.add("Goat");

        // set up the RecyclerView
        RecyclerView recyclerView = findViewById(R.id.rvAnimals);
        recyclerView.setLayoutManager(new LinearLayoutManager(this));
        adapter = new MyRecyclerViewAdapter(this, animalNames);
        adapter.setClickListener(this);
        recyclerView.setAdapter(adapter);
    }

    @Override
    public void onItemClick(View view, int position) {
        Toast.makeText(this, "You clicked " + adapter.getItem(position) + " on row number " + position, Toast.LENGTH_SHORT).show();
    }
}

注意，该活动实现了我们在适配器中定义的ItemClickListener接口。这使我们能够在onItemClick中处理行点击事件。

完成

就是这样。你现在应该能够运行你的项目，并得到与顶部图片类似的东西。

继续

在行之间添加分隔线

你可以像这样添加一个简单的分隔线

DividerItemDecoration dividerItemDecoration = new DividerItemDecoration(recyclerView.getContext(),
    layoutManager.getOrientation());
recyclerView.addItemDecoration(dividerItemDecoration);

如果您需要更复杂的内容，请参阅以下答案：

• 如何在RecyclerView中添加分隔线和空格？
• 如何缩进线性布局RecyclerView中的分隔符（即仅向ItemDecoration添加填充、边距或插图）

单击更改行颜色

请参见此答案以了解如何在单击行时更改背景颜色并添加涟漪效果。

更新行

请参见此答案以了解如何添加、删除和更新行。

进一步阅读

• CodePath
• YouTube教程
• Android RecyclerView示例（stacktips教程）
• Android中的RecyclerView：教程

- Suragch

---

非常好。这个代码可以工作，直到我添加一个按钮并尝试设置它的点击监听器。有什么想法为什么会干扰吗？ - john k

@johnktejik，从您提供的信息中很难确切知道您在谈论什么。这可能最好作为一个新问题来询问。我猜您的按钮正在处理运动事件，以便其他事物无法获取它。 - Suragch

@Suragch，感谢您的教程，它也适用于水平输出吗？ - coder

@程序员，不客气。是的，我已经用过这个来进行水平输出，效果一样。 - Suragch

这个答案需要更新为使用androidx。 - Jose Alcérreca

Answer 2

用于以下功能的Kotlin模板，最小化可重复使用的Recycler视图：

• 垂直布局
• 每行一个TextView
• 响应单击事件（单击和长按）

我知道这是一篇旧帖子，所以在此回答。添加此答案供将来参考：

在构建依赖项中添加Recycle view

  implementation 'com.google.android.material:material:1.4.0-alpha02'
    // RecyclerView
    implementation "androidx.recyclerview:recyclerview:1.2.0"

在布局中添加一个 RecyclerView。

   <androidx.recyclerview.widget.RecyclerView
            android:id="@+id/wifiList"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
           /> 

创建一个用于显示列表项的布局（list_item.xml）

<?xml version="1.0" encoding="utf-8"?>
<androidx.cardview.widget.CardView
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content">
    <LinearLayout
        android:padding="5dp"
        android:layout_width="match_parent"
        android:orientation="vertical"
        android:layout_height="wrap_content">

        <androidx.appcompat.widget.AppCompatTextView
            android:id="@+id/ssid"
            android:text="@string/app_name"
            android:layout_width="match_parent"
            android:textSize="17sp"
            android:layout_height="wrap_content" />
        
    </LinearLayout>

</androidx.cardview.widget.CardView>

现在创建一个最小的 Adapter 来保存数据，这里的代码很容易理解。

 class WifiAdapter(private val wifiList: ArrayList<ScanResult>) : RecyclerView.Adapter<WifiAdapter.ViewHolder>() {

     // holder class to hold reference
    inner class ViewHolder(view: View) : RecyclerView.ViewHolder(view) {
        //get view reference
        var ssid: TextView = view.findViewById(R.id.ssid) as TextView
    }

     override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
         // create view holder to hold reference
         return ViewHolder( LayoutInflater.from(parent.context).inflate(R.layout.list_item, parent, false))
     }

    override fun onBindViewHolder(holder: ViewHolder, position: Int) {
        //set values
        holder.ssid.text =  wifiList[position].SSID
    }

    override fun getItemCount(): Int {
        return wifiList.size
    }
      // update your data
     fun updateData(scanResult: ArrayList<ScanResult>) {
         wifiList.clear()
         notifyDataSetChanged()
         wifiList.addAll(scanResult)
         notifyDataSetChanged()

     }
 }

将此类添加到列表项上以处理单击和长按事件。

import android.content.Context;
import androidx.recyclerview.widget.RecyclerView
import androidx.recyclerview.widget.RecyclerView.OnItemTouchListener
import android.view.GestureDetector;
import android.view.MotionEvent;
import android.view.View;

public class RecyclerTouchListener implements RecyclerView.OnItemTouchListener {

    public interface ClickListener {
        void onClick(View view, int position);

        void onLongClick(View view, RecyclerView recyclerView, int position);

    }
    private GestureDetector gestureDetector;
    private ClickListener clickListener;

    public RecyclerTouchListener(Context context, final RecyclerView recyclerView, final ClickListener clickListener) {
        this.clickListener = clickListener;
        gestureDetector = new GestureDetector(context, new GestureDetector.SimpleOnGestureListener() {
            @Override
            public boolean onSingleTapUp(MotionEvent e) {
                return true;
            }

            @Override
            public void onLongPress(MotionEvent e) {
                View child = recyclerView.findChildViewUnder(e.getX(), e.getY());
                if (child != null && clickListener != null) {
                    clickListener.onLongClick(child,recyclerView,  recyclerView.getChildPosition(child));
                }
            }
        });
    }


    @Override
    public boolean onInterceptTouchEvent(RecyclerView rv, MotionEvent e) {
        View child = rv.findChildViewUnder(e.getX(), e.getY());
        if (child != null && clickListener != null && gestureDetector.onTouchEvent(e)) {
            clickListener.onClick(child, rv.getChildPosition(child));
        }
        return false;
    }

    @Override
    public void onTouchEvent(RecyclerView rv, MotionEvent e) {

    }

    @Override
    public void onRequestDisallowInterceptTouchEvent(boolean disallowIntercept) {

    }

最后将适配器设置到RecyclerView上，并添加触摸监听器以开始拦截列表项上的单击或双击触摸事件。

    wifiAdapter = WifiAdapter(ArrayList())

    wifiList.apply {
        // vertical layout
        layoutManager = LinearLayoutManager(applicationContext)
        // set adapter
        adapter = wifiAdapter

        // Touch handling
        wifiList.addOnItemTouchListener(RecyclerTouchListener(applicationContext, wifiList, object : RecyclerTouchListener.ClickListener {
            override fun onClick(view: View?, position: Int) {
                Toast.makeText(applicationContext, "RV OnCLickj " + position, Toast.LENGTH_SHORT).show()
            }

            override fun onLongClick(view: View, recyclerView: RecyclerView, position: Int) {
                Toast.makeText(applicationContext, "RV OnLongCLickj " + position, Toast.LENGTH_SHORT).show()
            }
        }
        ))
    }

奖励：更新数据

wifiAdapter.updateData(mScanResults as ArrayList<ScanResult>)

结果：

- Hitesh Sahu

---

RecyclerTouchListener 为什么要用 Java 编写？ - N.Barrett

Answer 3

这将是RecyclerView实现的最简单版本。

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <androidx.recyclerview.widget.RecyclerView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:id="@+id/recycler_view"/>

</FrameLayout>

list_item_view.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="46dp">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/textview"
        android:text="TextView"
        android:textSize="16dp" />

</LinearLayout>

CustomAdapter.java

public class CustomAdapter extends RecyclerView.Adapter<CustomAdapter.ViewHolder> {
  private List<String> data;
  public CustomAdapter (List<String> data){
    this.data = data;
  }

  @Override
  public CustomAdapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
    View rowItem = LayoutInflater.from(parent.getContext()).inflate(R.layout.list_item_view, parent, false);
    return new ViewHolder(rowItem);
  }

  @Override
  public void onBindViewHolder(CustomAdapter.ViewHolder holder, int position) {
    holder.textView.setText(this.data.get(position));
  }

  @Override
  public int getItemCount() {
    return this.data.size();
  }

  public static class ViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
    private TextView textView;

    public ViewHolder(View view) {
      super(view);
      view.setOnClickListener(this);
      this.textView = view.findViewById(R.id.textview);
    }

    @Override
    public void onClick(View view) {
      Toast.makeText(view.getContext(), "position : " + getLayoutPosition() + " text : " + this.textView.getText(), Toast.LENGTH_SHORT).show();
    }
  }
}

MainActivity.java

public class MainActivity extends AppCompatActivity {

  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    RecyclerView recyclerView = findViewById(R.id.recycler_view);
    
    recyclerView.setLayoutManager(new LinearLayoutManager(this));
    recyclerView.setAdapter(new CustomAdapter(generateData()));
    recyclerView.addItemDecoration(new DividerItemDecoration(this, DividerItemDecoration.VERTICAL));
  }

  private List<String> generateData() {
    List<String> data = new ArrayList<>();
    for (int i = 0; i < 100; i++) {
      data.add(String.valueOf(i) + "th Element");
    }
    return data;
  }

}

- Jin Lim

Answer 4

首先添加RecyclerView库。

implementation 'androidx.recyclerview:recyclerview:1.1.0'

创建模型类。

     public class UserModel implements Serializable {

    private String userName;


    public UserModel(String userName) {
        this.userName = userName;
    }

    public String getUserName() {
        return userName;
    }

    public void setUserName(String userName) {
        this.userName = userName;
    }
   }

创建适配器类。

public class UsersAdapter extends RecyclerView.Adapter<UsersAdapter.UsersAdapterVh> implements Filterable {

    private List<UserModel> userModelList;
    private List<UserModel> getUserModelListFiltered;
    private Context context;
    private SelectedUser selectedUser;

    public UsersAdapter(List<UserModel> userModelList,SelectedUser selectedUser) {
        this.userModelList = userModelList;
        this.getUserModelListFiltered = userModelList;
        this.selectedUser = selectedUser;
    }

    @NonNull
    @Override
    public UsersAdapter.UsersAdapterVh onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
        context = parent.getContext();

        return new UsersAdapterVh(LayoutInflater.from(context).inflate(R.layout.row_users,null));
    }

    @Override
    public void onBindViewHolder(@NonNull UsersAdapter.UsersAdapterVh holder, int position) {

        UserModel userModel = userModelList.get(position);

        String username = userModel.getUserName();
        String prefix = userModel.getUserName().substring(0,1);

        holder.tvUsername.setText(username);
        holder.tvPrefix.setText(prefix);

    }

    @Override
    public int getItemCount() {
        return userModelList.size();
    }

    @Override
    public Filter getFilter() {

        Filter filter = new Filter() {
            @Override
            protected FilterResults performFiltering(CharSequence charSequence) {
                FilterResults filterResults = new FilterResults();

                if(charSequence == null | charSequence.length() == 0){
                    filterResults.count = getUserModelListFiltered.size();
                    filterResults.values = getUserModelListFiltered;

                }else{
                    String searchChr = charSequence.toString().toLowerCase();

                    List<UserModel> resultData = new ArrayList<>();

                    for(UserModel userModel: getUserModelListFiltered){
                        if(userModel.getUserName().toLowerCase().contains(searchChr)){
                            resultData.add(userModel);
                        }
                    }
                    filterResults.count = resultData.size();
                    filterResults.values = resultData;

                }

                return filterResults;
            }

            @Override
            protected void publishResults(CharSequence charSequence, FilterResults filterResults) {

                userModelList = (List<UserModel>) filterResults.values;
                notifyDataSetChanged();

            }
        };
        return filter;
    }


    public interface SelectedUser{

        void selectedUser(UserModel userModel);

    }

    public class UsersAdapterVh extends RecyclerView.ViewHolder {

        TextView tvPrefix;
        TextView tvUsername;
        ImageView imIcon;
        public UsersAdapterVh(@NonNull View itemView) {
            super(itemView);
            tvPrefix = itemView.findViewById(R.id.prefix);
            tvUsername = itemView.findViewById(R.id.username);
            imIcon = itemView.findViewById(R.id.imageView);

            itemView.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View view) {
                    selectedUser.selectedUser(userModelList.get(getAdapterPosition()));
                }
            });


        }
    }
}

创建布局文件 row_uses.xml

    <?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical" android:layout_width="match_parent"
    android:layout_height="match_parent">

    <RelativeLayout
        android:layout_width="match_parent"
        android:padding="10dp"
        android:layout_height="wrap_content">

        <RelativeLayout
            android:layout_width="50dp"
            android:background="@drawable/users_bg"
            android:layout_height="50dp">
            <TextView
                android:id="@+id/prefix"
                android:layout_width="wrap_content"
                android:textSize="16sp"
                android:textColor="@color/headerColor"
                android:text="T"
                android:layout_centerInParent="true"
                android:layout_height="wrap_content"/>

        </RelativeLayout>
        <TextView
            android:id="@+id/username"
            android:layout_width="wrap_content"
            android:textSize="16sp"
            android:textColor="@color/headerColor"
            android:text="username"
            android:layout_marginStart="90dp"
            android:layout_centerVertical="true"
            android:layout_height="wrap_content"/>
        <ImageView
            android:layout_width="wrap_content"
            android:id="@+id/imageView"
            android:layout_margin="10dp"
            android:layout_alignParentEnd="true"
            android:src="@drawable/ic_navigate_next_black_24dp"
            android:layout_height="wrap_content"/>
    </RelativeLayout>

</LinearLayout>

查找recyclerview并填充数据。

Toolbar toolbar;
RecyclerView recyclerView;

List<UserModel> userModelList = new ArrayList<>();

String[] names = {"Richard","Alice","Hannah","David"};

UsersAdapter usersAdapter;


@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    recyclerView = findViewById(R.id.recyclerview);
    toolbar = findViewById(R.id.toolbar);

    this.setSupportActionBar(toolbar);
    this.getSupportActionBar().setTitle("");

    recyclerView.setLayoutManager(new LinearLayoutManager(this));
    recyclerView.addItemDecoration(new DividerItemDecoration(this,DividerItemDecoration.VERTICAL));

    for(String s:names){
        UserModel userModel = new UserModel(s);

        userModelList.add(userModel);
    }

    usersAdapter = new UsersAdapter(userModelList,this);

    recyclerView.setAdapter(usersAdapter);

}

在这里找到完整的教程和源代码：

Android RecyclerView

（注：本文中的 HTML 标签已保留）

- Richard Kamere

---

为什么要将context发送到用户适配器类中 usersAdapter = new UsersAdapter(userModelList,this);？ - Omar Boshra

@OmarBoshra this 指的是 SelectedUser 接口的实现。 - private static

Answer 5

这是一种较新的Kotlin解决方案，比这里写的许多答案要简单得多，它使用匿名类。

val items = mutableListOf<String>()

inner class ItemHolder(view: View): RecyclerView.ViewHolder(view) {
    var textField: TextView = view.findViewById(android.R.id.text1) as TextView
}

override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
    rvitems.layoutManager = LinearLayoutManager(context)
    rvitems.adapter = object : RecyclerView.Adapter<ItemHolder>() {

        override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ItemHolder {
            return ItemHolder(LayoutInflater.from(parent.context).inflate(android.R.layout.simple_list_item_1, parent, false))
        }

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

        override fun onBindViewHolder(holder: ItemHolder, position: Int) {
            holder.textField.text = items[position]
            holder.textField.setOnClickListener {
                Toast.makeText(context, "Clicked $position", Toast.LENGTH_SHORT).show()
            }
        }
    }
}

我自作主张使用了android.R.layout.simple_list_item_1，因为它更简单。我希望进一步简化并将ItemHolder作为内部类，但是我没能想出如何在外部类参数中引用它。

- Saifur Rahman Mohsin

---

我曾经差点放弃Kotlin和Android开发，因为没有简单的解决方案，直到我看到了你的。谢谢！ - ExeRhythm

有趣。那么你如何响应点击？ - SMBiggs

@SMBiggs 你是什么意思？处理点击事件的代码也在这个例子中的onBindViewHolder方法里面。 - Saifur Rahman Mohsin

我现在明白了 - 我的错。我不知怎么跳过了onBindViewHolder的那一部分。 - SMBiggs

这看起来不错，但这段代码究竟是属于哪部分的呢？ rvitems 是从哪里来的？ - Peter

啊，我猜这应该是在一个片段内吧？我将你的答案改编成了一个完整的活动，链接在这里：https://dev59.com/8VkR5IYBdhLWcg3w9RoO#74215835 - Peter

Answer 6

要开始使用，只需查看 Recycler View 中的内容。

Recycler View 适配器可以像这样：

class CustomAdapter: RecyclerView.Adapter<CustomAdapter.ViewHolder>() {
    var data =  listOf<String>()
        set(value) {
            field = value
            notifyDataSetChanged()
        }
    override fun getItemCount() =data.size

    override fun onBindViewHolder(holder: ViewHolder, position: Int) {
        holder.txt.text= data[position]
    }
    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
        return ViewHolder(
            LayoutInflater.from(parent.context).inflate(R.layout.item_view, parent, false)
        )
    }


    class ViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView){
        val txt: TextView = itemView.findViewById(R.id.item_text_view)
    }
}

将适配器附加到回收站并将数据附加到适配器。

val view = findViewById<RecyclerView>(R.id.recycler_view)                                              
val adapter = CustomAdapter()                                                                          
val data = listOf("text1", "text2", "text3")
adapter.data = data                                                                             
view.layoutManager = LinearLayoutManager(this, RecyclerView.VERTICAL, false)
view.adapter = adapter       
            

- Harsh

---

不完整...未显示item_text_view.xml或item_view.xml。 - Peter

Answer 7

根据不同的来源，我创建了一个使用简单库的RecyclerView的简单实现。

在build.gradle中添加以下行：

implementation 'com.hereshem.lib:awesomelib:2.0.1'

通过在activity_main.xml中添加MyRecyclerView来创建一个RecyclerView：

<com.hereshem.lib.recycler.MyRecyclerView
        android:id="@+id/recycler"
        app:layoutManager="LinearLayoutManager"
        android:layout_width="match_parent"
        android:layout_height="match_parent"/>

现在在MainActivity中，通过传递需要绑定的类的名称来创建一个ViewHolder。

public static class EVHolder extends MyViewHolder<Events> {
    TextView date, title, summary;
    public EVHolder(View v) {
        super(v);
        date = v.findViewById(R.id.date);
        title = v.findViewById(R.id.title);
        summary = v.findViewById(R.id.summary);
    }
    @Override
    public void bindView(Events c) {
        date.setText(c.date);
        title.setText(c.title);
        summary.setText(c.summary);
    }
}

通过在适配器中传递项目、类和布局，仅使用很少的代码创建项目列表变量和适配器

List<Events> items = new ArrayList<>();
MyRecyclerView recycler = findViewById(R.id.recycler);
RecyclerViewAdapter adapter = new RecyclerViewAdapter(this, items, EVHolder.class, R.layout.row_event);
recycler.setAdapter(adapter);

可以通过以下代码添加ClickListener：

recycler.setOnItemClickListener(new MyRecyclerView.OnItemClickListener() {
    @Override
    public void onItemClick(int position) {
        Toast.makeText(MainActivity.this, "Recycler Item Clicked " + position, Toast.LENGTH_SHORT).show();
    }
});

一切都已完成。

更多示例和实现可以在这里找到。 希望这有所帮助！！！

- Hem Shrestha

---

什么是单一活动？ - john k

错误：找不到符号 summary = v.findViewById(R.id.summary); ^ 符号：变量summary 位置：类id EVHolder.java:15：错误：方法未覆盖或实现超类型的方法 @Override ^ EVHolder.java:17：错误：找不到符号 date.setText(c.date); - john k

@johnktejik R.id.summary是布局资源文件的ID。 请查看此布局文件https://github.com/hereshem/Easy-RecyclerView-Library/blob/master/app/src/main/res/layout/row_event.xml - Hem Shrestha

Answer 8

现在您需要一个适配器来处理所有的RecyclerView

• 一个适配器可以用于所有的RecyclerView。因此不需要onBindViewHolder，也不需要onCreateViewHolder处理。
• 没有Java/Kotlin类中设置适配器的代码。请查看示例类。
• 您可以使用绑定适配器为每个列表设置事件和自定义数据。

我在这里展示了通过一个适配器设置两个不同的RecyclerView的方法 -

activity_home.xml

<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:app="http://schemas.android.com/apk/res-auto">

    <data>

        <variable
            name="listOne"
            type="java.util.List"/>

        <variable
            name="listTwo"
            type="java.util.List"/>

        <variable
            name="onItemClickListenerOne"
            type="com.ks.nestedrecyclerbindingexample.callbacks.OnItemClickListener"/>

        <variable
            name="onItemClickListenerTwo"
            type="com.ks.nestedrecyclerbindingexample.callbacks.OnItemClickListener"/>

    </data>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical">

        <android.support.v7.widget.RecyclerView
            rvItemLayout="@{@layout/row_one}"
            rvList="@{listOne}"
            rvOnItemClick="@{onItemClickListenerOne}"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            app:layoutManager="android.support.v7.widget.LinearLayoutManager"
            />

        <android.support.v7.widget.RecyclerView
            rvItemLayout="@{@layout/row_two}"
            rvList="@{listTwo}"
            rvOnItemClick="@{onItemClickListenerTwo}"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            app:layoutManager="android.support.v7.widget.LinearLayoutManager"
            />

    </LinearLayout>

</layout>

你可以看到，我从布局中传递了列表、项目布局ID和点击监听器。

rvItemLayout="@{@layout/row_one}"
rvList="@{listOne}"
rvOnItemClick="@{onItemClickListenerOne}"

这些自定义属性是由BindingAdapter创建的。

public class BindingAdapters {
    @BindingAdapter(value = {"rvItemLayout", "rvList", "rvOnItemClick"}, requireAll = false)
    public static void setRvAdapter(RecyclerView recyclerView, int rvItemLayout, List rvList, @Nullable OnItemClickListener onItemClickListener) {
        if (rvItemLayout != 0 && rvList != null && rvList.size() > 0)
            recyclerView.setAdapter(new GeneralAdapter(rvItemLayout, rvList, onItemClickListener));
    }
}

现在从活动中，您传递列表和点击监听器，如下：

HomeActivity.java

public class HomeActivity extends AppCompatActivity {
    ActivityHomeBinding binding;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        binding = DataBindingUtil.setContentView(this, R.layout.activity_home);
        binding.setListOne(new ArrayList()); // pass your list or set list from response of API
        binding.setListTwo(new ArrayList());
        binding.setOnItemClickListenerOne(new OnItemClickListener() {
            @Override
            public void onItemClick(View view, Object object) {
                if (object instanceof ModelParent) {
                    // TODO: your action here
                }
            }
        });
        binding.setOnItemClickListenerTwo(new OnItemClickListener() {
            @Override
            public void onItemClick(View view, Object object) {
                if (object instanceof ModelChild) {
                    // TODO: your action here  
                }
            }
        });
    }
}

你不需要读太多内容，直接从我的github资源库克隆/下载完整示例并自己尝试。

你可以在上述资源库中看到GeneralAdapter.java。

如果在设置数据绑定时遇到问题，请查看此答案。

- Khemraj Sharma

Answer 9

依赖项

compile 'com.android.support:appcompat-v7:25.3.1'
compile 'com.android.support:design:25.3.1'
compile 'com.android.support:multidex:1.0.1'
compile 'com.android.support:cardview-v7:25.3.1'
compile 'com.android.support:support-v4:25.3.1'
compile 'com.lguipeng.bubbleview:library:1.0.0'
compile 'com.larswerkman:HoloColorPicker:1.5'
compile 'com.mcxiaoke.volley:library-aar:1.0.0'

一种针对点击项的类

import android.content.Context;
import android.support.v7.widget.RecyclerView;
import android.view.GestureDetector;
import android.view.MotionEvent;
import android.view.View;

public class RecyclerItemClickListener implements RecyclerView.OnItemTouchListener {
    private OnItemClickListener mListener;

    public interface OnItemClickListener {
        public void onItemClick(View view, int position);
    }

    GestureDetector mGestureDetector;

    public RecyclerItemClickListener(Context context, OnItemClickListener listener) {
        mListener = listener;
        mGestureDetector = new GestureDetector(context, new GestureDetector.SimpleOnGestureListener() {
            @Override
            public boolean onSingleTapUp(MotionEvent e) {
                return true;
            }
        });
    }

    @Override
    public boolean onInterceptTouchEvent(RecyclerView view, MotionEvent e) {
        View childView = view.findChildViewUnder(e.getX(), e.getY());
        if (childView != null && mListener != null && mGestureDetector.onTouchEvent(e)) {
            mListener.onItemClick(childView, view.getChildPosition(childView));
            return true;
        }
        return false;
    }

    @Override
    public void onTouchEvent(RecyclerView view, MotionEvent motionEvent) { }

    @Override
    public void onRequestDisallowInterceptTouchEvent(boolean disallowIntercept) {

    }


}

RecyclerView 的第二类

import android.annotation.SuppressLint;
import android.app.ProgressDialog;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.net.Uri;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentTransaction;
import android.support.v4.content.LocalBroadcastManager;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Toast;

import com.android.volley.DefaultRetryPolicy;
import com.android.volley.Request;
import com.android.volley.RequestQueue;
import com.android.volley.Response;
import com.android.volley.VolleyError;
import com.android.volley.toolbox.StringRequest;
import com.android.volley.toolbox.Volley;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import java.util.ArrayList;

public class SLByTopics extends Fragment {


    public static ArrayList<MByTopics> byTopicsMainArrayList=new ArrayList<>();


    TabRefreshReceiver tabRefreshReceiver;
    RecyclerView recyclerView;
    SAdpByTopics sAdpByTopics;
    public ArrayList<MByTopics> mByTopicsArrayList=new ArrayList<>();
    ProgressDialog progressDialog;

    public SLByTopics(){
    }

    @Override
    public void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
    }

    @Override
    public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.sl_fragment_by_topics, container, false);

        progressDialog = new ProgressDialog(getActivity());
        if (IsOnline.isNetworkAvailable(getActivity())) {
            getCategoryTree();
        } else{
            IsOnline.showNoInterNetMessage(getActivity());
        }
        tabRefreshReceiver = new TabRefreshReceiver();
       LocalBroadcastManager.getInstance(getContext()).registerReceiver(tabRefreshReceiver, new IntentFilter("BY_TOPICS"));

        setUpView(view);
        return view;
    }

    private void setUpView(View view) {

        recyclerView=(RecyclerView)view.findViewById(R.id.by_topics_list_recyclerView);
        LinearLayoutManager linearLayoutManager=new LinearLayoutManager(getActivity());
        linearLayoutManager.setOrientation(LinearLayoutManager.VERTICAL);
        recyclerView.setLayoutManager(linearLayoutManager);
    }

    @Override
    public void onResume() {
        super.onResume();

        recyclerView.addOnItemTouchListener(new RecyclerItemClickListener(getActivity(), new RecyclerItemClickListener.OnItemClickListener() {
            @Override
            public void onItemClick(View view, final int position) {

                if (mByTopicsArrayList.get(position).getChild().size()>0){
                    Intent intent = new Intent(getActivity(), SByTopicCategory.class);
                    intent.putExtra("selectedCategoryName",mByTopicsArrayList.get(position).getCatname());
                    intent.putExtra("jsonData",mByTopicsArrayList.get(position).getMainTopicJson());
                    startActivity(intent);
                    getActivity().overridePendingTransition(R.anim.activity_in, R.anim.activity_out);
                }else {
                    Intent intent = new Intent(getActivity(), SByCategoryQuestionList.class);
                    intent.putExtra("selectedSubCategoryName",mByTopicsArrayList.get(position).getCatname());
                    intent.putExtra("catID",mByTopicsArrayList.get(position).getId());
                    startActivity(intent);
                    getActivity().overridePendingTransition(R.anim.activity_in, R.anim.activity_out);
                }
            }
        }));

    }

    private class TabRefreshReceiver extends BroadcastReceiver {
        @Override
        public void onReceive(Context context, Intent intent) {
            try {
                FragmentTransaction ft = getFragmentManager().beginTransaction();
                ft.detach(SLByTopics.this).attach(SLByTopics.this).commit();
                LocalBroadcastManager.getInstance(getContext()).unregisterReceiver(tabRefreshReceiver);
            } catch (Exception e) {
                e.printStackTrace();
            }

        }
    }

    private void getCategoryTree() {
        progressDialog.setMessage("Please Wait...");
        progressDialog.setCancelable(false);
        progressDialog.show();

        StringRequest stringRequest = new StringRequest(Request.Method.POST, Const.HOSTNAME + Const.STUDENT_GET_CATEGORY_TREE,
                new Response.Listener<String>() {
                    @SuppressLint("LongLogTag")
                    @Override
                    public void onResponse(String response) {
                        try {
                            JSONObject object = new JSONObject(response);
                            String status = object.getString("status");
                            int i = Integer.parseInt(status);

                            switch (i) {

                                case 0:
                                    progressDialog.dismiss();
//                                    Toast.makeText(getActivity(), "getCategorySuccess", Toast.LENGTH_SHORT).show();
                                    Log.e("getCategoryTree Response", "getCategoryTree Response : " + response);

                                    try {    
                                        byTopicsMainArrayList.clear();
                                        JSONArray info = object.getJSONArray("info");
                                        if (info.length() > 0) {
                                            for (i = 0; i < info.length(); i++) {
                                                JSONObject data = info.getJSONObject(i);
                                                MByTopics mByTopics = new MByTopics();
                                                mByTopics.setId(data.getString("id"));
                                                mByTopics.setCatname(data.getString("catname"));
                                                mByTopics.setMainTopicJson(data.toString());

                                                JSONArray topicChildren = data.getJSONArray("children");
                                                ArrayList<SMByTopicCategory> byChildrenArrayList = new ArrayList<>();

                                                for (int j = 0; j < topicChildren.length(); j++) {
                                                    JSONObject topicChildrenData = topicChildren.getJSONObject(j);
                                                    SMByTopicCategory smByTopicCategory = new SMByTopicCategory();
                                                    smByTopicCategory.setId(topicChildrenData.getString("id"));
                                                    smByTopicCategory.setCatname(topicChildrenData.getString("catname"));
                                                    smByTopicCategory.setChildTopicJson(topicChildrenData.toString());

                                                    JSONArray topicChildrenQuestion = topicChildrenData.getJSONArray("children");
                                                    ArrayList<SMByTopicSubCategory> byChildrenSubArrayList = new ArrayList<>();

                                                    for (int k = 0; k < topicChildrenQuestion.length(); k++) {
                                                        JSONObject topicChildrenSubData = topicChildrenQuestion.getJSONObject(k);
                                                        SMByTopicSubCategory smByTopicSubCategory = new SMByTopicSubCategory();
                                                        smByTopicSubCategory.setId(topicChildrenSubData.getString("id"));
                                                        smByTopicSubCategory.setCatname(topicChildrenSubData.getString("catname"));
                                                        smByTopicSubCategory.setChildSubTopicJson(topicChildrenSubData.toString());

                                                        byChildrenSubArrayList.add(smByTopicSubCategory);
                                                    }

                                                    smByTopicCategory.setQuestions(byChildrenSubArrayList);

                                                    byChildrenArrayList.add(smByTopicCategory);
                                                }
                                                mByTopics.setChild(byChildrenArrayList);
                                                byTopicsMainArrayList.add(mByTopics);
                                            }


                                            mByTopicsArrayList.clear();
                                            mByTopicsArrayList=byTopicsMainArrayList;
                                            sAdpByTopics=new SAdpByTopics(mByTopicsArrayList,getActivity());
                                            recyclerView.setAdapter(sAdpByTopics);
                                            sAdpByTopics.notifyDataSetChanged();

                                        }

                                    }catch (Exception e){
                                        e.printStackTrace();
                                    }
                                    break;

                                default:
                                    progressDialog.dismiss();
//                                    Toast.makeText(getActivity(), "getCategoryError : " + response, Toast.LENGTH_SHORT).show();
                                    Log.e("getCategoryTree Not Response", "getCategoryTree Uploading Not Response : " + response);
                            }

                        } catch (JSONException e) {
                            e.printStackTrace();
                        }
                    }
                },
                new Response.ErrorListener() {
                    @Override
                    public void onErrorResponse(VolleyError error) {
                        progressDialog.dismiss();
                        Log.e("getCategoryTree Error :","getCategoryTree Error :"+error.getMessage());
//                        Toast.makeText(getActivity(), error.getMessage(), Toast.LENGTH_LONG).show();
                    }
                }){

        };/* {
            @Override
            protected Map<String, String> getParams() throws AuthFailureError {

                Map<String, String> map = new HashMap<String, String>();
//                map.put("uid", String.valueOf(ConfigManager.getUserId()));
                return map;
            }
        };*/

        stringRequest.setRetryPolicy(new DefaultRetryPolicy(
                0,
                DefaultRetryPolicy.DEFAULT_MAX_RETRIES,
                DefaultRetryPolicy.DEFAULT_BACKOFF_MULT));

        RequestQueue requestQueue = Volley.newRequestQueue(getActivity());
        requestQueue.add(stringRequest);
    }
}

Recycler视图项的适配器类

import android.app.Activity;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
import java.util.ArrayList;

public class SAdpByTopics extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
        ArrayList<MByTopics> topicsArrayList=new ArrayList<>();
        Activity activity;

     public SAdpByTopics(ArrayList<MByTopics> topicsArrayList,Activity activity){
        this.topicsArrayList=topicsArrayList;
        this.activity=activity;
     }

     @Override
     public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View itemeView= LayoutInflater.from(parent.getContext()).inflate(R.layout.list_item_by_topic_list,parent,false);
        RecyclerView.ViewHolder holder=new Holder(itemeView);
        holder.setIsRecyclable(false);
        return holder;
     }

     @Override
     public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
         final Holder classHolder = (Holder) holder;
         try{
             classHolder.txt_topic_name.setText(topicsArrayList.get(position).getCatname());
         }catch (Exception e){
             e.printStackTrace();
         }
     }

     @Override
     public int getItemCount() {
        return topicsArrayList.size();
     }


class Holder extends RecyclerView.ViewHolder implements View.OnClickListener {
    TextView txt_topic_name;

    public Holder(View itemView) {
        super(itemView);
        txt_topic_name = (TextView) itemView.findViewById(R.id.txt_topic_name);
    }

    @Override
    public void onClick(View v) {

    }
}
}

模块类

public class MByTopics {

    String id;
    String topicName;
    String catname;
    String MainTopicJson;
    ArrayList<SMByTopicCategory> child;
    ArrayList<SMByTopicSubCategory> questions;

    public void setId(String id){
        this.id=id;
    }
    public String getId(){
        return  id;
    }

    public void setCatname(String catname) {
        this.catname = catname;
    }

    public String getCatname() {
        return catname;
    }

    public void setTopicName(String topicName) {
        this.topicName = topicName;
    }
    public String getTopicName() {
        return topicName;
    }

    public void setChild(ArrayList<SMByTopicCategory> child) {
        this.child = child;
    }

    public String getMainTopicJson() {
        return MainTopicJson;
    }

    public void setMainTopicJson(String mainTopicJson) {
        MainTopicJson = mainTopicJson;
    }

    public ArrayList<SMByTopicCategory> getChild() {
        return child;
    }

    public void setQuestions(ArrayList<SMByTopicSubCategory> questions) {
        this.questions = questions;
    }

    public ArrayList<SMByTopicSubCategory> getQuestions() {
        return questions;
    }

    public ArrayList<MByTopics> getByTopicList() {
        ArrayList<MByTopics> mByTopicsArrayList = new ArrayList<>();

        for (int i=0;i<11;i++){
            MByTopics mQuestionBankCategory=new MByTopics();

            if (i==1 || i== 5|| i==9){
                mQuestionBankCategory.setTopicName("Microeconomics");
            }else  if (i==2 || i== 10|| i==6) {
                mQuestionBankCategory.setTopicName("Macroeconomics");
            }else {
                mQuestionBankCategory.setTopicName("Current Isssues");
            }

            mByTopicsArrayList.add(mQuestionBankCategory);
        }

        return mByTopicsArrayList;
    }

}

- Ranjit Barve

---

explanations would be nice - ThomasEdwin

代码不干净，也没有解释！ - Gary Chen

Answer 10

由于我还不能发表评论，所以我会将链接作为答案发布。 我已经找到了一个简单而且组织良好的RecyclerView教程。

http://www.androiddeft.com/2017/10/01/recyclerview-android/

除此之外，当您要在活动中添加RecyclerView时，您需要按照以下步骤进行操作，如下链接所述：

• 将RecyclerView组件添加到您的布局文件中
• 创建一个类，将其作为列表行显示
• 创建一个布局文件，该文件是您列表中一行的布局
• 现在我们需要一个自定义适配器，因此通过扩展父类RecyclerView.Adapter来创建自定义适配器
• 在onCreate中将RecyclerView添加到您的MainActivity中
• 添加分隔符
• 添加触摸监听器

- noone