android：回收器视图适配器

我不熟悉recyclerView小部件，我想从api url获取数据并将数据列在我的recyclerView中，我有以下类：

recyclerAdapter

，

recyclerView

，

MainActivity

，

row

数据已成功从api加载，但未在recycler视图中设置从api接收的json字符串，并且recycler视图显示为白色和空。任何人都可以在我的代码中找到问题？

MainActivity.java代码是：

public class MainActivity extends AppCompatActivity {
    final String member_id = "2";
    final String get_cash_url = "http://famila1.ir/khabgah/get_khabgah_cash.php?member_id=" + member_id;

    private RecyclerView rc;
    private RecyclerView.Adapter adapter;
    private List<recyclerView> cashList;

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

        rc = findViewById(R.id.rc);
        rc.setHasFixedSize(true);
        rc.setLayoutManager(new LinearLayoutManager(this));
        cashList = new ArrayList<>();
        loadUrlData();

    }

    private void loadUrlData() {
        final ProgressDialog progressDialog = new ProgressDialog(this);
        progressDialog.setMessage("Loading...");
        progressDialog.show();
        StringRequest stringRequest = new StringRequest(Request.Method.GET,
                get_cash_url, new Response.Listener<String>() {
            @Override
            public void onResponse(String response) {
                System.out.println(response);
                progressDialog.dismiss();
                try {
                    JSONObject jsonObject = new JSONObject(response);
                    JSONArray array = jsonObject.getJSONArray("bedehkariHa");
                    for (int i = 0; i < array.length(); i++) {
                        JSONObject jo = array.getJSONObject(i);
                        recyclerView temp = new recyclerView(jo.getString("hazine"), jo.getString("tarikh"), jo.getString("tozihat"), jo.getString("member_id"), "kir");
                        cashList.add(temp);
                    }
                    adapter = new recyclerAdapter(cashList, getApplicationContext());
                    rc.setAdapter(adapter);
                } catch (JSONException e) {
                    e.printStackTrace();
                }
            }
        }
                , new Response.ErrorListener() {
            @Override
            public void onErrorResponse(VolleyError error) {
                progressDialog.dismiss();
                progressDialog.setMessage("somthing was wrong during runnig app...");
                progressDialog.show();
                System.out.println("error: "+error);
            }
        }
        );
        RequestQueue requestQueue = Volley.newRequestQueue(this);
        requestQueue.add(stringRequest);


    }
}

}

}

这是row.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" android:background="@android:color/white" >

    <android.support.v7.widget.CardView
            android:layout_width="match_parent"
            android:layout_height="match_parent">
        <LinearLayout
                android:orientation="vertical"
                android:layout_width="match_parent"
                android:layout_height="wrap_content" android:padding="5dp"
                android:background="@android:color/holo_blue_bright" android:layout_marginBottom="5dp"
        >
            <LinearLayout
                    android:orientation="horizontal"
                    android:layout_width="match_parent"
                    android:layout_height="match_parent" android:padding="3dp"
                    android:background="@android:color/holo_blue_dark">
                <TextView
                        android:text="سهم شما:"
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content" android:id="@+id/tarikh_hazine2"
                        android:textSize="18sp" android:textColor="@android:color/holo_red_dark"
                        android:textStyle="bold"
                />
                <TextView
                        android:text="قالب پرداخت"
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content" android:id="@+id/bedehkariha_dong"
                        android:layout_weight="1"
                        android:textSize="18sp" android:textColor="@android:color/black"/>
                <TextView
                        android:text="مبلغ کل: "
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content" android:id="@+id/mablaq_hazine2"
                        android:textSize="18sp" android:textColor="@android:color/holo_red_dark"
                        android:textStyle="bold"/>
                <TextView
                        android:text="مبلغ کل"
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content" android:id="@+id/mablaq_hazine" android:layout_weight="1"
                        android:textSize="18sp" android:textColor="@android:color/black"/>
            </LinearLayout>
            <LinearLayout
                    android:orientation="horizontal"
                    android:layout_width="match_parent"
                    android:layout_height="match_parent" android:padding="3dp"
                    android:background="@android:color/holo_blue_dark">
                <TextView
                        android:text="تاریخ:"
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content" android:id="@+id/tarikh_hazine22"
                        android:textSize="18sp" android:textColor="@android:color/holo_red_dark"
                        android:textStyle="bold"
                />
                <TextView
                        android:text="تاریخ"
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content" android:id="@+id/tarikh_hazine" android:layout_weight="1"
                        android:textSize="18sp" android:textColor="@android:color/black"
                        android:inputType="textMultiLine"
                />
            </LinearLayout>
            <LinearLayout
                    android:orientation="horizontal"
                    android:layout_width="match_parent"
                    android:layout_height="match_parent" android:padding="3dp"
                    android:background="@android:color/holo_blue_dark">
                <TextView
                        android:text="توضیحات: "
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content" android:id="@+id/babate_hazine2"
                        android:textSize="18sp" android:textColor="@android:color/holo_red_dark"
                        android:textStyle="bold"
                />
                <TextView
                        android:text="هزینه بابت......"
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content" android:id="@+id/babate_hazine" android:layout_weight="1"
                        android:textSize="18sp" android:textColor="@android:color/black"
                        android:inputType="textMultiLine"
                        android:gravity="right"/>
            </LinearLayout>
            <LinearLayout
                    android:orientation="horizontal"
                    android:layout_width="match_parent"
                    android:layout_height="match_parent" android:layout_marginTop="2dp">
                <LinearLayout
                        android:orientation="vertical"
                        android:layout_width="match_parent"
                        android:layout_height="match_parent" android:layout_weight="1" android:padding="2dp">
                    <TextView
                            android:text="پرداخت از: "
                            android:layout_width="match_parent"
                            android:layout_height="wrap_content" android:id="@+id/pardakhtaz" android:layout_weight="1"
                            android:textSize="18sp" android:textColor="@android:color/black"
                            android:fadingEdge="none"
                            android:background="@android:color/white" android:gravity="center"/>
                    <TextView
                            android:layout_width="match_parent"
                            android:layout_height="wrap_content" android:id="@+id/pardakhtaz1" android:layout_weight="1"
                            android:textSize="18sp" android:textColor="@android:color/black"
                            android:fadingEdge="none" android:gravity="right"
                            android:background="#FF75AD06" android:padding="2dp"/>
                    <TextView
                            android:layout_width="match_parent"
                            android:layout_height="wrap_content" android:id="@+id/pardakhtaz2" android:layout_weight="1"
                            android:textSize="18sp" android:textColor="@android:color/black"
                            android:fadingEdge="none" android:gravity="right"
                            android:background="@android:color/holo_green_dark" android:padding="2dp"
                    />
                    <TextView
                            android:layout_width="match_parent"
                            android:layout_height="wrap_content" android:id="@+id/pardakhtaz3" android:layout_weight="1"
                            android:textSize="18sp" android:textColor="@android:color/black"
                            android:fadingEdge="none" android:gravity="right"
                            android:background="#FF75AD06" android:padding="2dp"/>
                    <TextView
                            android:layout_width="match_parent"
                            android:layout_height="wrap_content" android:id="@+id/pardakhtaz4" android:layout_weight="1"
                            android:textSize="18sp" android:textColor="@android:color/black"
                            android:fadingEdge="none" android:gravity="right"
                            android:background="@android:color/holo_green_dark" android:padding="2dp"
                    />
                    <TextView
                            android:layout_width="match_parent"
                            android:layout_height="wrap_content" android:id="@+id/pardakhtaz5" android:layout_weight="1"
                            android:textSize="18sp" android:textColor="@android:color/black"
                            android:fadingEdge="none" android:gravity="right"
                            android:background="#75ad06" android:padding="2dp"/>
                    <TextView
                            android:layout_width="match_parent"
                            android:layout_height="wrap_content" android:id="@+id/pardakhtaz6" android:layout_weight="1"
                            android:textSize="18sp" android:textColor="@android:color/black"
                            android:fadingEdge="none" android:gravity="right"
                            android:background="@android:color/holo_green_dark" android:padding="2dp"
                    />
                </LinearLayout>
                <LinearLayout
                        android:orientation="vertical"
                        android:layout_width="match_parent"
                        android:layout_height="match_parent" android:layout_weight="1" android:padding="2dp">
                    <TextView
                            android:text="هزینه شریکی با:"
                            android:layout_width="match_parent"
                            android:layout_height="wrap_content" android:id="@+id/moshtarak_ba"
                            android:layout_weight="1"
                            android:textSize="18sp" android:textColor="@android:color/black"
                            android:fadingEdge="none"
                            android:background="@android:color/white" android:gravity="center"/>
                    <TextView
                            android:layout_width="match_parent"
                            android:layout_height="wrap_content" android:id="@+id/moshtarak_ba1"
                            android:layout_weight="1"
                            android:textSize="18sp" android:textColor="@android:color/black"
                            android:fadingEdge="none" android:gravity="right"
                            android:background="#FFF10D0D" android:padding="2dp"/>
                    <TextView
                            android:layout_width="match_parent"
                            android:layout_height="wrap_content" android:id="@+id/moshtarak_ba2"
                            android:layout_weight="1"
                            android:textSize="18sp" android:textColor="@android:color/black"
                            android:fadingEdge="none" android:gravity="right"
                            android:background="@android:color/holo_red_dark" android:padding="2dp"
                    />
                    <TextView
                            android:layout_width="match_parent"
                            android:layout_height="wrap_content" android:id="@+id/moshtarak_ba3"
                            android:layout_weight="1"
                            android:textSize="18sp" android:textColor="@android:color/black"
                            android:fadingEdge="none" android:gravity="right"
                            android:background="#FFF10D0D" android:padding="2dp"/>
                    <TextView
                            android:layout_width="match_parent"
                            android:layout_height="wrap_content" android:id="@+id/moshtarak_ba4"
                            android:layout_weight="1"
                            android:textSize="18sp" android:textColor="@android:color/black"
                            android:fadingEdge="none" android:gravity="right"
                            android:background="@android:color/holo_red_dark" android:padding="2dp"
                    />
                    <TextView
                            android:layout_width="match_parent"
                            android:layout_height="wrap_content" android:id="@+id/moshtarak_ba5"
                            android:layout_weight="1"
                            android:textSize="18sp" android:textColor="@android:color/black"
                            android:fadingEdge="none" android:gravity="right"
                            android:background="#FFF10D0D" android:padding="2dp"/>
                    <TextView
                            android:layout_width="match_parent"
                            android:layout_height="wrap_content" android:id="@+id/moshtarak_ba6"
                            android:layout_weight="1"
                            android:textSize="18sp" android:textColor="@android:color/black"
                            android:fadingEdge="none" android:gravity="right"
                            android:background="@android:color/holo_red_dark" android:padding="2dp"
                    />
                </LinearLayout>
            </LinearLayout>
        </LinearLayout>
    </android.support.v7.widget.CardView>
</LinearLayout>

---

我首先遇到解析问题。更改

 JSONArray array = jsonObject.getJSONArray("bedehkariHa");

致：

---

然后首先检查我遇到的解析问题。更改

 JSONArray array = jsonObject.getJSONArray("bedehkariHa");

致：

---

然后根据JSON的结果检查

，键bedehkariHa不存在，这可能导致解析错误，即JSONException。因此，与此相反：

 JSONArray array = jsonObject.getJSONArray("bedehkariHa");

使用此命令获取与bedehkari_ha关联的JSONArray：

---

根据JSON的结果，密钥bedehkariHa不存在，这可能导致解析错误，即JSONException。因此，与此相反：

 JSONArray array = jsonObject.getJSONArray("bedehkariHa");

使用此命令获取与bedehkari_ha关联的JSONArray：

---

我先看看你的一般做法。 你似乎正在实例化一个截击请求…我打赌这不是你应用程序中唯一的一个

制作一个包含应用程序上下文的“NetworkService”singleton，并将其作为服务层调用……而不是为您需要的每个类调用一个新的Volley实例

这里是我为我的应用程序写的一个…我省略了很多方法，留给你们一个GetRequest方法。您可以在服务中添加参数的URL编码

您只需在活动/片段中调用：

 HashMap<String,String> urlParams = new HashMap<>();
        urlParams.put("param1","value1");

        VolleyRequestService.getInstance(this).getJSONObject(urlParams, true, new GetJSONObjectRequestable() {
            @Override
            public void onSuccessfulAPIResponse(JSONObject response) {

            }

            @Override
            public void onFailedAPIResponse(VolleyRequestService.ErrorType errorType, String description) {

            }
        },"https://myendpoint.com/endpoint.php");

---

我先看看你的一般做法。 你似乎正在实例化一个截击请求…我打赌这不是你应用程序中唯一的一个

制作一个包含应用程序上下文的“NetworkService”singleton，并将其作为服务层调用……而不是为您需要的每个类调用一个新的Volley实例

这里是我为我的应用程序写的一个…我省略了很多方法，留给你们一个GetRequest方法。您可以在服务中添加参数的URL编码

您只需在活动/片段中调用：

 HashMap<String,String> urlParams = new HashMap<>();
        urlParams.put("param1","value1");

        VolleyRequestService.getInstance(this).getJSONObject(urlParams, true, new GetJSONObjectRequestable() {
            @Override
            public void onSuccessfulAPIResponse(JSONObject response) {

            }

            @Override
            public void onFailedAPIResponse(VolleyRequestService.ErrorType errorType, String description) {

            }
        },"https://myendpoint.com/endpoint.php");

---

它是否显示错误？异常？是否显示错误？例外？

 JSONArray array = jsonObject.getJSONArray("bedehkariHa");

 JSONArray array = jsonObject.getJSONArray("bedehkari_ha");

 HashMap<String,String> urlParams = new HashMap<>();
        urlParams.put("param1","value1");

        VolleyRequestService.getInstance(this).getJSONObject(urlParams, true, new GetJSONObjectRequestable() {
            @Override
            public void onSuccessfulAPIResponse(JSONObject response) {

            }

            @Override
            public void onFailedAPIResponse(VolleyRequestService.ErrorType errorType, String description) {

            }
        },"https://myendpoint.com/endpoint.php");

package devdroidjonno.com.tests.Networking;

import android.content.Context;
import android.util.Log;

import com.android.volley.Request;
import com.android.volley.RequestQueue;
import com.android.volley.toolbox.JsonObjectRequest;
import com.android.volley.toolbox.Volley;

import java.util.HashMap;
import java.util.Map;

public class VolleyRequestService {
    private static final String DEBUG = "VolleyRequestService";
    private static final String authCode = "87fe987vwefb987eb9w87wv";
    private static VolleyRequestService ourInstance = null;
    private static RequestQueue requestQueue;

    private VolleyRequestService(Context applicationContext) {
        this.requestQueue = Volley.newRequestQueue(applicationContext);
        Log.d(DEBUG, "Init Volley Service " + this.hashCode());
    }

    public static VolleyRequestService getInstance(Context context) {
        if (ourInstance == null) {
            ourInstance = new VolleyRequestService(context.getApplicationContext());
        }
        return ourInstance;
    }

    // A GET request to an endpoint that returns a JSONObject. 
    public void getJSONObject(HashMap<String, String> urlParams, final boolean requiresAuthHeader, final GetJSONObjectRequestable callback, String endpointURL) {
        endpointURL += "?";
        for (Map.Entry mapEntry : urlParams.entrySet()) {
            endpointURL += mapEntry.getKey() + "=" + mapEntry.getValue() + "&";
        }
        Log.d(DEBUG, endpointURL);
        requestQueue.add(new JsonObjectRequest(Request.Method.GET, endpointURL, null, response -> {
            Log.d(DEBUG, response.toString());
            try {
                if (response.has("error")) {
                    callback.onFailedAPIResponse(ErrorType.APIERROR, response.getString("error"));
                } else {
                    callback.onSuccessfulAPIResponse(response);
                }
            } catch (Exception e) {
                callback.onFailedAPIResponse(ErrorType.EXCEPTION, e.getLocalizedMessage());
                e.printStackTrace();
            }
        }, error -> callback.onFailedAPIResponse(ErrorType.VOLLEYERROR, error.getMessage())) {
            @Override
            public Map<String, String> getHeaders() {
                HashMap<String, String> headers = new HashMap<>();
                if (requiresAuthHeader) headers.put("Authorization", authCode);
                return headers;
            }
        });
    }

    public enum ErrorType {
        NOERROR, APIERROR, VOLLEYERROR, AUTHERROR, EXCEPTION
    }

}

package devdroidjonno.com.tests.Networking;

import org.json.JSONException;
import org.json.JSONObject;

import java.io.IOException;


public interface GetJSONObjectRequestable {
    void onSuccessfulAPIResponse(JSONObject response) throws JSONException, IOException;

    void onFailedAPIResponse(VolleyRequestService.ErrorType errorType, String description);
}