如何使用不同类型的项目制作 RecyclerView？ [复制]答案

【问题标题】：How to make RecyclerView with different types of items? [duplicate]如何使用不同类型的项目制作 RecyclerView？ [复制]
【发布时间】：2020-12-23 00:27:11
【问题描述】：

我有不同类型的项目列表。在这种情况下如何制作 RecyclerView？我有用户类。在这个类中，我有变量地址地址类型。地址类也有自己的变量。我试着按照我的建议去做，但它不能正常工作。仅显示用户数据。地址数据不输出。

我的第一个项目类：

public class User {
    private Integer id;
    private String name;
    private String username;
    private String email;
    private Address address;

getter，setter }

我的 seconf 项目类：

public class Address {
    private String street;
    private String suite;
    private String city;
getters, setters
}

我的适配器类：

   public class ResultAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
    private static int TYPE_ADDRESS = 1;
    private static int TYPE_USER = 2;

    private LayoutInflater layoutInflater;
    private Context context;
    private List<User> users;

    public ResultAdapter(Context context, List<User> users) {
        this.users = users;
        this.layoutInflater = LayoutInflater.from(context);
        this.context = context;
    }

    @NonNull
    @Override
    public RecyclerView.ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
        if (viewType == TYPE_ADDRESS){
            return new AddressViewHolder (layoutInflater.inflate(R.layout.list_item, parent, false));
        }else if(viewType == TYPE_USER){
            return new UsersViewHolder(layoutInflater.inflate(R.layout.list_item, parent, false));
        }else return new AddressViewHolder(layoutInflater.inflate(R.layout.list_item, parent, false));
    }

    @Override
    public void onBindViewHolder(@NonNull RecyclerView.ViewHolder holder, int position) {
if (holder instanceof AddressViewHolder){
Address address = new Address();
((AddressViewHolder) holder).city.setText(address.getCity());
} else if (holder instanceof UsersViewHolder){

    final User user = users.get(position);
    ((UsersViewHolder) holder).name.setText(user.getName());

}
    }


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

    @Override
    public int getItemViewType(int position) {
      if (position==1){
          return TYPE_ADDRESS;
      }else
          return TYPE_USER;
    }

public static class AddressViewHolder extends RecyclerView.ViewHolder{
final TextView city;
    public AddressViewHolder(@NonNull View itemView) {
        super(itemView);
        city = itemView.findViewById(R.id.city);
    }
}

   public static class  UsersViewHolder extends RecyclerView.ViewHolder{
       final TextView name;
        public UsersViewHolder(@NonNull View itemView) {
            super(itemView);
            name = itemView.findViewById(R.id.name);

        }
    }
}

【问题讨论】：

谢谢。我认为这是我需要的。
如果我的回答对你有帮助，请标记为回答。谢谢
@Akki，我按照你的建议做了，做了一些改动。但现在只显示用户数据。这些地址不显示。请看，我改变了我的问题。
两个原因：一个是 getItemViewType 内部如果 position 是 1 则返回类型地址。你也有用户类里面的地址，所以你需要解释你想要实现什么的问题

标签： android android-recyclerview adapter

【解决方案1】：

        public class GenericAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
                private static int TYPE_ADDRESS = 1;
                private static int TYPE_USER = 2;
            
                private LayoutInflater layoutInflater;
                private List<User> users;
                private Context context;
            
                public GenericAdapter(Context context, List<User> users) {
                    this.users = users;
                    this.layoutInflater = LayoutInflater.from(context);
                    this.context = context;
                }
            
                @NonNull
                @Override
                public RecyclerView.ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
                   if(viewType == TYPE_ADDRESS){
                       return AddressViewHolder(layoutInflater.inflate(R.layout.list_item, parent, false));
                   }else if(viewType == TYPE_USER){
                       return UsersViewHolder(layoutInflater.inflate(R.layout.list_item, parent, false));
                   }else return AddressViewHolder(layoutInflater.inflate(R.layout.list_item, parent, false));
                }
            
                @Override
                public void onBindViewHolder(@NonNull RecyclerView.ViewHolder holder, int position) {
                    if(holder instanceof AddressViewHolder){
                        /*Your binding */
                    }else if(holder instanceof UsersViewHolder){
                        /*Your binding */
                    }
            
                }
            
                @Override
                public int getItemCount() {
                    return users.size();
                }
            
                @Override
                public int getItemViewType(int position) {
                    /*Please specify your logic here of selecting the type optionally you can use the position to query the data and decide on it*/
                    return (position % 2 == 0 )? TYPE_ADDRESS : TYPE_USER;
                }
            
                 class AddressViewHolder extends RecyclerView.ViewHolder{
            
                    public AddressViewHolder(@NonNull View itemView) {
                        super(itemView);
                    }
                }
            
                 class UsersViewHolder extends RecyclerView.ViewHolder{
            
                    public UsersViewHolder(@NonNull View itemView) {
                        super(itemView);
                    }
                }
            
            }

【讨论】：