带有卡片视图的 RecyclerView 适配器仅显示哈希图中的最后一项

Question

我有一个包含 cardview 的 recyclerview，我将我的数据存储在 hashmap 中，但只有最后一项显示在 recyclerview 上，如附图所示。当我传递一个列表时，如果我删除 forloop 并放置 .get(position) 代替，一切似乎都可以工作。

package www.atralk.co.atralk;

import android.app.DatePickerDialog;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.os.Bundle;
import android.text.format.DateFormat;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.webkit.WebSettings;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import android.widget.ArrayAdapter;
import android.widget.DatePicker;
import android.widget.EditText;
import android.widget.Spinner;
import android.widget.TextView;
import android.widget.Toast;

import androidx.annotation.NonNull;
import androidx.appcompat.app.AlertDialog;
import androidx.recyclerview.widget.RecyclerView;

import com.firebase.geofire.GeoFire;
import com.google.firebase.auth.FirebaseAuth;
import com.google.firebase.database.DatabaseReference;
import com.google.firebase.database.FirebaseDatabase;

import java.io.UnsupportedEncodingException;
import java.util.Arrays;
import java.util.Calendar;
import java.util.HashMap;
import java.util.List;
import java.util.Locale;
import java.util.Map;

public class AdapterRequestList  extends RecyclerView.Adapter<AdapterRequestList.MyViewHolders>
{

    private String key;
    private Spinner cn,sn;
    private String hairstyleName;
    private String customerCategory;
    private String sessionDate;
    private String cComment;
    private String price;
    private String clientID;
    private String isPaid;
    private DatabaseReference history ;
    private DatabaseReference stylistHistoryRef ;
    private String stylistID;
    private Map<String,Request_View> map;
    private Request_View itemDetails;
    private int no1,no2;
    private String assignedRef;
    private Context context;
    private String categoryItem;
    private String styleItem;
    private WebView payWebView;
    private Checkout_Page checkoutPage;
    private TextView priceText=null;
    Request_Details request_details;
    public AdapterRequestList(Map<String,Request_View> map, Context c) {
        //this.itemList = List;
        this.map=map;
        this.context = c;
    }

    @Override
    public www.atralk.co.atralk.AdapterRequestList.MyViewHolders onCreateViewHolder(ViewGroup parent, int viewType)
    {
        return new MyViewHolders(LayoutInflater.from(context).inflate(R.layout.recycler_item, parent, false));
    }

    @Override
  public void onBindViewHolder(final AdapterRequestList.MyViewHolders holder,  int position)
  {
       int i = 0;
        for ( Map.Entry<String, Request_View> entry : map.entrySet())
        {
            if(position == i)
            {
                key = entry.getKey();
                itemDetails = entry.getValue();
                holder.title.setText(itemDetails.getCustomerCategory());
                holder.description.setText(itemDetails.getHairstyleName());
            }
            i++;
        }

    }
    private String getDate(Long time)
    {
        Calendar cal = Calendar.getInstance(Locale.getDefault());
        cal.setTimeInMillis(time*1000);
        String date = DateFormat.format("MM-dd-yyyy", cal).toString();
        return date;
    }
    @Override
    public int getItemCount() {
        return this.map.size();
    }
    class MyViewHolders extends RecyclerView.ViewHolder
    {
        TextView title,description,options;
        public MyViewHolders(@NonNull View itemView)
        {
            super(itemView);
            title=itemView.findViewById(R.id.txtTitle);
            description=itemView.findViewById(R.id.txtDescription);
            options=itemView.findViewById(R.id.txtOption);
        }
    }
} 

图像显示一个项目，但我有一个包含 3 个元素的哈希图。 当我将一些愚蠢的数据放入数组列表中时，它可以工作，但是我的数据存储在哈希图中 enter image description here

Answer 1

也许在构造函数中将map 转换为List 并改用列表：

public class AdapterRequestList  extends RecyclerView.Adapter<AdapterRequestList.MyViewHolders>
{

//add a field in your class
private List<Request_View> list;
.......
.......

//constructor
public AdapterRequestList(Map<String,Request_View> map, Context c) {
    //this.itemList = List;
    this.map=map;
    this.context = c;

    //convert map to a list

    for ( Map.Entry<String, Request_View> entry : map.entrySet()){
     list.add(entry.getValue());
    }


}

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

@Override
public void onBindViewHolder(final AdapterRequestList.MyViewHolders holder,  int position){

Request_View itemDetails = list.get(position); 

holder.title.setText(itemDetails.getCustomerCategory());
holder.description.setText(itemDetails.getHairstyleName());



}