Firebase 回收器适配器不显示数据

Question

我习惯于将populateViewHolder 与firebase 回收器适配器一起使用，但onBindViewHolder 是根据this post 执行此操作的新方法。我试过onBindViewHolder，但它没有显示任何东西。 我做错了什么？

这是我的代码

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

mDatabase = FirebaseDatabase.getInstance().getReference().child("Users");
    mUsersList = (RecyclerView) findViewById(R.id.usersList);
    mUsersList.setHasFixedSize(true);
    mUsersList.setLayoutManager(new LinearLayoutManager(this));}


 @Override
protected void onStart() {
    super.onStart();
 FirebaseRecyclerOptions<Users> options =
          new FirebaseRecyclerOptions.Builder<Users>()
                  .setQuery(mDatabase, Users.class)
                  .build();

  FirebaseRecyclerAdapter<Users, UsersViewHolder> adapter = new FirebaseRecyclerAdapter<Users, UsersViewHolder>(options) {

      @Override
      public UsersViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {

          View view = LayoutInflater.from(parent.getContext())
                  .inflate(R.layout.users_single_layout, parent, false);
          return new UsersViewHolder(view);
      }

      @Override
      protected void onBindViewHolder(@NonNull UsersViewHolder holder, int position, @NonNull Users model) {
            holder.setName(model.getName());
      }

  };
  mUsersList.setAdapter(adapter);

}

public static class UsersViewHolder extends RecyclerView.ViewHolder {

   View mView;
    public UsersViewHolder(View itemView) {
        super(itemView);
        mView = itemView;
    }

    public void setName(String name){

        TextView userNames = (TextView) mView.findViewById(R.id.textView2);
        userNames.setText(name);
    }
}}

我的模型类的代码。

public class Users {

public String name;
public String image;
public String status;

public Users(){


}

public Users(String name, String image, String status) {
    this.name = name;
    this.image = image;
    this.status = status;
}

public String getName() {
    return name;
}

public void setName(String name) {
    this.name = name;
}

public String getImage() {
    return image;
}

public void setImage(String image) {
    this.image = image;
}

public String getStatus() {
    return status;
}

public void setStatus(String status) {
    this.status = status;
}}

我的自定义布局

 <?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">


    <de.hdodenhof.circleimageview.CircleImageView
        android:layout_width="50dp"
        android:layout_height="50dp"
        android:src="@drawable/common_google_signin_btn_icon_dark_focused"
        android:id="@+id/circleImageView2" />

    <TextView
        android:id="@+id/textView2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentTop="true"
        android:layout_marginLeft="89dp"
        android:layout_marginStart="89dp"
        android:layout_toEndOf="@+id/circleImageView2"
        android:layout_toRightOf="@+id/circleImageView2"
        android:text="TextView" />

    <TextView
        android:id="@+id/textView3"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignBottom="@+id/circleImageView2"
        android:layout_alignLeft="@+id/textView2"
        android:layout_alignStart="@+id/textView2"
        android:text="TextView" />
</RelativeLayout>

Answer 1

我可以在 firebase 中查看您的表 Users 吗？添加 onCreateViewHolder 和 onBindViewHolder 日志，看看他们是否调用了。

Answer 2

确保您在 firebase 项目中设置了读取规则。将读取设置为 true。

检查firebase项目中的规则：

Answer 3

您可以添加：

 adapter.startListening();

之后：

mUsersList.setAdapter(adapter);

它应该看起来像：

mUsersList.setAdapter(adapter);

adapter.startListening();