Recyclview在调试模式下显示数据，但在正常运行中无法工作

Question

我正在开发一个Android应用程序，遇到了一些问题。当我运行应用程序时，回收站中没有任何内容，但如果我在调试模式下检查应用程序，则数据可以成功显示在回收站中。我已经检查过我的网络服务是否正常工作并且成功提供数据。我该如何解决这个问题？

ManageQuestionActivity.java

public class ManageQuestionActivity extends AppCompatActivity implements RecyclerView.OnScrollChangeListener{

    private static final String TAG = MainActivity.class.getSimpleName();
    private RecyclerView listView;
    private RecyclerView.LayoutManager layoutManager;
    private RecyclerView.Adapter adapter;
    private QuestionsListAdapter listAdapter;
    private List<QuestionsItem> timeLineItems;
    private int requestCount = 1;
    private ProgressDialog pDialog;
    public static String id, message, token, encodedString;
    int pageCount, totalPages;
    SQLiteHandler db;
    SessionManager session;
    ConnectionDetector cd;
    EditText edtSearch;
    Boolean isInternetPresent = false;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_manage_question);
        getSupportActionBar().setDisplayHomeAsUpEnabled(true);

        listView = (RecyclerView) findViewById(R.id.list);
        edtSearch = (EditText) findViewById(R.id.edtSearch);
        listView.setHasFixedSize(true);
        layoutManager = new LinearLayoutManager(this);
        listView.setLayoutManager(layoutManager);
        //Adding an scroll change listener to recyclerview
        listView.setOnScrollChangeListener(this);

        // Progress dialog
        pDialog = new ProgressDialog(this);
        pDialog.setCancelable(false);

        cd = new ConnectionDetector(this);
        isInternetPresent = cd.isConnectingToInternet();

        db = new SQLiteHandler(this);

        // session manager
        session = new SessionManager(this);

        // Fetching user details from sqlite
        HashMap<String, String> user = db.getUserDetails();
        id = user.get("id");
        token = user.get("token");

        getData();

        timeLineItems = new ArrayList<>();

        adapter = new QuestionsListAdapter(timeLineItems, this);
        listView.setAdapter(adapter);

    }

    public void getTimeLineData(final String token, final String page) {


        String tag_string_req = "req_register";
        // making fresh volley request and getting json
        StringRequest strReq = new StringRequest(Request.Method.POST, AppConfig.questions, new Response.Listener<String>() {

            @Override
            public void onResponse(String response) {
                VolleyLog.d(TAG, "Response: " + response.toString());
                if (response != null) {
                    try {
                        JSONObject jObj = new JSONObject(response);
                        boolean error = jObj.getBoolean("status");
                        String message = jObj.getString("message");
                        if (error) {
                            totalPages = jObj.getInt("totalPages");
                            pageCount = jObj.getInt("page");

                            int limit = jObj.getInt("limit");
                            parseJsonFeed(response);
                        }

                    } catch (Exception e) {

                    }

                }
            }
        }, new Response.ErrorListener() {

            @Override
            public void onErrorResponse(VolleyError error) {
                VolleyLog.d(TAG, "Error: " + error.getMessage());
            }
        }) {

            @Override
            protected Map<String, String> getParams() {
                // Posting params to register url
                Map<String, String> params = new HashMap<String, String>();
                params.put("my_token", token);
                params.put("page", page);
                params.put("limit", "20");

                return params;
            }
        };

        // Adding request to request queue
        AppController.getInstance().addToRequestQueue(strReq, tag_string_req);

    }

    private void parseJsonFeed(String response) {
        try {
            JSONObject jsonObj = new JSONObject(response);
            JSONArray feedArray = jsonObj.getJSONArray("data");
            for (int i = 0; i < feedArray.length(); i++) {
                JSONObject feedObj = (JSONObject) feedArray.get(i);

                QuestionsItem item = new QuestionsItem();
                item.setId(feedObj.getInt("id"));
                item.setQuestion(feedObj.getString("question"));
                String options = feedObj.getString("multi_ans_option");
                String[] parts = options.split("\\|");
                String part1 = parts[0];
                String part2 = parts[1];
                String part3 = parts[2];
                String part4 = parts[3];
                item.setAnsOne(part1);
                item.setAnsTwo(part2);
                item.setAnsThree(part3);
                item.setAnsFour(part4);
                item.setAnswer(feedObj.getString("answer"));
                timeLineItems.add(item);
            }

            // notify data changes to list adapater
            adapter.notifyDataSetChanged();


        } catch (JSONException e) {
            e.printStackTrace();
        }
    }

    private void getData() {
        //Adding the method to the queue by calling the method getDataFromServer
        getTimeLineData(token, String.valueOf(requestCount));
        //Incrementing the request counter
        requestCount++;
    }

    //This method would check that the recyclerview scroll has reached the bottom or not
    private boolean isLastItemDisplaying(RecyclerView recyclerView) {
        if (recyclerView.getAdapter().getItemCount() != 0) {
            int lastVisibleItemPosition = ((LinearLayoutManager) recyclerView.getLayoutManager()).findLastCompletelyVisibleItemPosition();
            if (lastVisibleItemPosition != RecyclerView.NO_POSITION && lastVisibleItemPosition == recyclerView.getAdapter().getItemCount() - 1)

                return true;
        }
        return false;
    }

    @Override
    public void onScrollChange(View v, int scrollX, int scrollY, int oldScrollX, int oldScrollY) {
        //Ifscrolled at last then
        if (isLastItemDisplaying(listView)) {
            //Calling the method getdata again
            getData();
        }
    }
}

activity_manage_question.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical">

    <android.support.v7.widget.RecyclerView
        android:id="@+id/list"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:divider="@null" />

</LinearLayout>

QuestionsItem.java

public class QuestionsItem {
    private int id;
    private String question, ansOne, ansTwo, ansThree, ansFour, answer;

    public QuestionsItem() {
    }

    public QuestionsItem(int id, String question, String ansOne, String ansTwo, String ansThree, String ansFour, String answer) {
        super();
        this.id = id;
        this.question = question;
        this.ansOne = ansOne;
        this.ansTwo = ansTwo;
        this.ansThree = ansThree;
        this.ansFour = ansFour;
        this.answer = answer;
    }

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getQuestion() {
        return question;
    }

    public void setQuestion(String question) {
        this.question = question;
    }

    public String getAnsOne() {
        return ansOne;
    }

    public void setAnsOne(String ansOne) {
        this.ansOne = ansOne;
    }

    public String getAnsTwo() {
        return ansTwo;
    }

    public void setAnsTwo(String ansTwo) {
        this.ansTwo = ansTwo;
    }

    public String getAnsThree() {
        return ansThree;
    }

    public void setAnsThree(String ansThree) {
        this.ansThree = ansThree;
    }

    public String getAnsFour() {
        return ansFour;
    }

    public void setAnsFour(String ansFour) {
        this.ansFour = ansFour;
    }

    public String getAnswer() {
        return answer;
    }

    public void setAnswer(String answer) {
        this.answer = answer;
    }
}

QuestionsListAdapter.java

public class QuestionsListAdapter extends RecyclerView.Adapter<QuestionsListAdapter.ViewHolder> {
    private List<QuestionsItem> timeLineItems;
    String message, storyId, token, ide;
    private Context context;
    ImageLoader imageLoader = AppController.getInstance().getImageLoader();
    ConnectionDetector cd;
    Boolean isInternetPresent = false;
    private ProgressDialog pDialog;
    private SessionManager session;
    private SQLiteHandler db;
    int newPosition;

    public QuestionsListAdapter(List<QuestionsItem> timeLineItems, Context context) {
        super();
        this.context = context;
        this.timeLineItems = timeLineItems;
    }

    @Override
    public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.questios_item, parent, false);
        ViewHolder viewHolder = new ViewHolder(v);
        return viewHolder;
    }

    @Override
    public void onBindViewHolder(final ViewHolder holder, final int position) {

        pDialog = new ProgressDialog(context);
        pDialog.setCancelable(false);

        db = new SQLiteHandler(context);

        // session manager
        session = new SessionManager(context);

        // Fetching user details from sqlite
        HashMap<String, String> user = db.getUserDetails();
        token = user.get("token");

        //Getting the particular item from the list
        QuestionsItem item =  timeLineItems.get(position);

        holder.txtQues.setText(item.getQuestion());

        holder.txtAnsOne.setText(item.getAnsOne());

        holder.txtAnsTwo.setText(item.getAnsTwo());

        holder.txtAnsThree.setText(item.getAnsThree());

        holder.txtAnsFour.setText(item.getAnsFour());

        holder.txtAns.setText(item.getAnswer());

        holder.btnEdit.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {

                final QuestionsItem m = timeLineItems.get(position);

                String ide = String.valueOf(m.getId());
                String ques = String.valueOf(m.getQuestion());
                String Option1 = String.valueOf(m.getAnsOne());
                String Option2 = String.valueOf(m.getAnsTwo());
                String Option3 = String.valueOf(m.getAnsThree());
                String Option4 = String.valueOf(m.getAnsFour());
                String answer = String.valueOf(m.getAnswer());

                Intent intent = new Intent(context, UpdateQuestionActivity.class);
                intent.putExtra("id", ide);
                intent.putExtra("ques", ques);
                intent.putExtra("option1", Option1);
                intent.putExtra("option2", Option2);
                intent.putExtra("option3", Option3);
                intent.putExtra("option4", Option4);
                intent.putExtra("answer", answer);
                context.startActivity(intent);
            }
        });

        holder.btnDelete.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                final QuestionsItem m = timeLineItems.get(position);
                newPosition = holder.getAdapterPosition();
                ide = String.valueOf(m.getId());
                alertBox();
            }
        });

    }

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

    @Override
    public int getItemViewType(int position)
    {
        return position;
    }

    class ViewHolder extends RecyclerView.ViewHolder{

        TextView txtQues, txtAnsOne, txtAnsTwo, txtAnsThree, txtAnsFour, txtAns, btnEdit, btnDelete;

        //Initializing Views
        public ViewHolder(View itemView) {
            super(itemView);
            txtQues = (TextView) itemView.findViewById(R.id.txtQues);
            txtAnsOne = (TextView) itemView.findViewById(R.id.txtAnsOne);
            txtAnsTwo = (TextView) itemView.findViewById(R.id.txtAnsTwo);
            txtAnsThree = (TextView) itemView.findViewById(R.id.txtAnsThree);
            txtAnsFour = (TextView) itemView.findViewById(R.id.txtAnsFour);
            txtAns = (TextView) itemView.findViewById(R.id.txtAns);
            btnEdit = (TextView) itemView.findViewById(R.id.btnEdit);
            btnDelete = (TextView) itemView.findViewById(R.id.btnDelete);
        }
    }

    public void alertBox(){

        AlertDialog.Builder builder = new AlertDialog.Builder(context);
        //Uncomment the below code to Set the message and title from the strings.xml file
        //builder.setMessage(R.string.dialog_message) .setTitle(R.string.dialog_title);

        //Setting message manually and performing action on button click
        builder.setMessage("Do you want to delete question ?")
                .setCancelable(false)
                .setPositiveButton("Yes", new DialogInterface.OnClickListener() {
                    public void onClick(DialogInterface dialog, int id) {

                        // Check for empty data in the form

                            cd = new ConnectionDetector(context);
                            isInternetPresent = cd.isConnectingToInternet();

                            if (isInternetPresent){

                                DeleteQuestion(token, ide);

                            }else {
                                final SweetAlertDialog alert = new SweetAlertDialog(context, SweetAlertDialog.WARNING_TYPE);
                                alert.setTitleText("No Internet");
                                alert.setContentText("No connectivity. Please check your internet.");
                                alert.show();
                            }
                    }
                })
                .setNegativeButton("No", new DialogInterface.OnClickListener() {
                    public void onClick(DialogInterface dialog, int id) {
                        //  Action for 'NO' Button
                        dialog.cancel();
                    }
                });

        //Creating dialog box
        AlertDialog alert = builder.create();
        //Setting the title manually
        alert.setTitle("Question");
        alert.show();
    }

    private void DeleteQuestion(final String token, final String qid) {
        // Tag used to cancel the request
        String tag_string_req = "req_register";

        pDialog.setMessage("Please wait ...");
        showDialog();

        StringRequest strReq = new StringRequest(Request.Method.POST, AppConfig.updateQues, new Response.Listener<String>() {

            @Override
            public void onResponse(String response) {
                hideDialog();

                try {
                    JSONObject jObj = new JSONObject(response);
                    boolean error = jObj.getBoolean("status");
                    if (error) {
                        String errorMsg = jObj.getString("message");
                        Toast.makeText(context, errorMsg, Toast.LENGTH_SHORT).show();
                        timeLineItems.remove(newPosition);
                        notifyItemRemoved(newPosition);
                        notifyItemRangeChanged(newPosition, timeLineItems.size());


                    } else {

                        // Error occurred in registration. Get the error
                        // message
                        String errorMsg = jObj.getString("message");
                        Toast.makeText(context, errorMsg, Toast.LENGTH_LONG).show();
                    }
                } catch (JSONException e) {
                    e.printStackTrace();
                }

            }
        }, new Response.ErrorListener() {

            @Override
            public void onErrorResponse(VolleyError error) {
                Toast.makeText(context, "Oops something went wrong...", Toast.LENGTH_LONG).show();
                hideDialog();
            }
        }) {

            @Override
            protected Map<String, String> getParams() {
                // Posting params to register url
                Map<String, String> params = new HashMap<String, String>();
                params.put("my_token", token);
                params.put("qid", qid);

                return params;
            }

        };

        // Adding request to request queue
        AppController.getInstance().addToRequestQueue(strReq, tag_string_req);
    }

    private void showDialog() {
        if (!pDialog.isShowing())
            pDialog.show();
    }

    private void hideDialog() {
        if (pDialog.isShowing())
            pDialog.dismiss();
    }
}

questios_item.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="vertical">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical"
        android:padding="5dp"
        android:background="@color/white">

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:padding="5dp"
            android:orientation="horizontal">

            <TextView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="Question : "
                android:textColor="#000000"
                android:textSize="15sp" />

            <TextView
                android:id="@+id/txtQues"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:textSize="@dimen/feed_item_profile_name"
                android:textStyle="bold" />

        </LinearLayout>

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:padding="5dp"
            android:orientation="horizontal">

            <TextView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="Option 1 : "
                android:textColor="#000000"
                android:textSize="15sp" />

            <TextView
                android:id="@+id/txtAnsOne"
                android:layout_width="fill_parent"
                android:layout_height="wrap_content"
                android:textSize="@dimen/feed_item_profile_name"
                android:textStyle="bold" />

        </LinearLayout>

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:padding="5dp"
            android:orientation="horizontal">

            <TextView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="Option 2 : "
                android:textColor="#000000"
                android:textSize="15sp" />

            <TextView
                android:id="@+id/txtAnsTwo"
                android:layout_width="fill_parent"
                android:layout_height="wrap_content"
                android:textSize="@dimen/feed_item_profile_name"
                android:textStyle="bold" />

        </LinearLayout>

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:padding="5dp"
            android:orientation="horizontal">

            <TextView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="Option 3 : "
                android:textColor="#000000"
                android:textSize="15sp" />

            <TextView
                android:id="@+id/txtAnsThree"
                android:layout_width="fill_parent"
                android:layout_height="wrap_content"
                android:textSize="@dimen/feed_item_profile_name"
                android:textStyle="bold" />

        </LinearLayout>

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:padding="5dp"
            android:orientation="horizontal">

            <TextView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="Option 4 : "
                android:textColor="#000000"
                android:textSize="15sp" />

            <TextView
                android:id="@+id/txtAnsFour"
                android:layout_width="fill_parent"
                android:layout_height="wrap_content"
                android:textSize="@dimen/feed_item_profile_name"
                android:textStyle="bold" />

        </LinearLayout>

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:padding="5dp"
            android:orientation="horizontal">

            <TextView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="Answer : "
                android:textColor="#000000"
                android:textSize="15sp" />

            <TextView
                android:id="@+id/txtAns"
                android:layout_width="fill_parent"
                android:layout_height="wrap_content"
                android:textSize="@dimen/feed_item_profile_name"
                android:textStyle="bold" />

        </LinearLayout>

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:orientation="horizontal"
            android:weightSum="2">

            <TextView android:id="@+id/btnEdit"
                android:layout_width="0dp"
                android:layout_height="30dp"
                android:text="Edit"
                android:background="@drawable/rounded_square_comment"
                android:gravity="center"
                android:textColor="#000000"
                android:layout_weight="1"
                android:textSize="15sp" />

            <TextView
                android:id="@+id/btnDelete"
                android:layout_width="0dp"
                android:layout_height="30dp"
                android:text="Delete"
                android:background="@drawable/rounded_square_comment"
                android:gravity="center"
                android:textColor="#000000"
                android:layout_weight="1"
                android:textSize="15sp" />

        </LinearLayout>

    </LinearLayout>

</LinearLayout>

- Moin Khan

---

API调用中有任何错误信息吗？ - Aefits

没有错误消息，因为我的网络服务成功地提供了数据，并且我已经在调试中进行了检查。 - Moin Khan

在请求数据之前，您应该设置适配器。 - Rahul

不确定这是否有帮助，但由于您只有一种视图类型，getItemViewType应该返回一个常量。 - Hai

@MoinKhan - 请尝试实现notifyDataSetChanged在onResponse完成后。 - Amod Gokhale

{btsdaf} - Moin Khan

Answer 1

listView.setAdapter不应该放在这里，请删除

    timeLineItems = new ArrayList<>();

    adapter = new QuestionsListAdapter(timeLineItems, this);
    listView.setAdapter(adapter); // Cut from Here

粘贴到此方法中：

 private void parseJsonFeed(String response) {
    try {
        JSONObject jsonObj = new JSONObject(response);
        JSONArray feedArray = jsonObj.getJSONArray("data");
        for (int i = 0; i < feedArray.length(); i++) {
            JSONObject feedObj = (JSONObject) feedArray.get(i);

            QuestionsItem item = new QuestionsItem();
            item.setId(feedObj.getInt("id"));
            item.setQuestion(feedObj.getString("question"));
            String options = feedObj.getString("multi_ans_option");
            String[] parts = options.split("\\|");
            String part1 = parts[0];
            String part2 = parts[1];
            String part3 = parts[2];
            String part4 = parts[3];
            item.setAnsOne(part1);
            item.setAnsTwo(part2);
            item.setAnsThree(part3);
            item.setAnsFour(part4);
            item.setAnswer(feedObj.getString("answer"));
            timeLineItems.add(item);

            listView.setAdapter(adapter);  //Paste Here
        }

        // notify data changes to list adapater
        adapter.notifyDataSetChanged();


    } catch (JSONException e) {
        e.printStackTrace();
    }
}

- Sikander Bhutto