Question

我在主布局上以这种方式创建简单的recyclerView：

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout  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="com.safarayaneh.recycletest.MainActivity">

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

然后为它创建适配器：

public class RecycleAdapter extends RecyclerView.Adapter<RecycleAdapter.MyHolder> {

    private List<User> users;
    public RecycleAdapter(List<User> users) {
        this.users = users;
    }

    @Override
    public MyHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.user_item, parent, false);
        MyHolder holder = new MyHolder(view);
        return holder;
    }

    @Override
    public void onBindViewHolder(MyHolder holder, int position) {
        User user = users.get(position);
        holder.name.setText(user.getName());
        holder.lName.setText(user.getlName());
    }

    @Override
    public int getItemCount() {
        return 0;
    }

    public class MyHolder extends RecyclerView.ViewHolder {
        TextView name;
        TextView lName;

        public MyHolder(View itemView) {
            super(itemView);

            name = (TextView) itemView.findViewById(R.id.tvName);
            lName = (TextView) itemView.findViewById(R.id.tvfamily);
        }
    }
}

这是我的Activity类：

 public class MainActivity extends AppCompatActivity {

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

        List<User> users = new ArrayList<>();

        for (int i = 0; i < 20; i++) {
            users.add(new User("pedro " + i, "ggg " + i));
        }

        RecyclerView recyclerView = (RecyclerView) findViewById(R.id.recycleView);
        LinearLayoutManager manager = new LinearLayoutManager(this);
        manager.setOrientation(LinearLayoutManager.VERTICAL);
        recyclerView.setLayoutManager(manager);
        RecycleAdapter adapter = new RecycleAdapter(users);
        recyclerView.setAdapter(adapter);
    }
}

和我的pojo用户类：

    public class User implements Serializable {
    private String name;
    private String lName;

    public User(String name, String lName) {
        this.name = name;
        this.lName = lName;
    }

    public String getName() {
        return name;
    }

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

    public String getlName() {
        return lName;
    }

    public void setlName(String lName) {
        this.lName = lName;
    }
}

但我不知道为什么我的简单列表不会出现在我的回收站视图中？我以前创造过，一切都很好，但现在我不知道为什么我不能！究竟我的错误在哪里？

Answer 1

只需在RecycleAdapter上更新：

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

Answer 2

尝试此更改 List

getItemCount

Answer 3

还尝试使用以下行：（在recyclerView.setLayoutManager（manager）之后）

recyclerView.setItemAnimator(new DefaultItemAnimator());

也在适配器类中：

@Override
    public int getItemCount() {
        return (null != this.users ? this.users.size() : 0);
    }

Answer 4

recyclerView项目的计数来自方法getItemCount（），因此您需要返回大小。

public int getItemCount(){return users.size();}

不要在RecyclerView上显示我的列表

4 个答案: