Question

我正在使用ListView来填充JSON数据。我想显示所有相应的值，但ListView中只设置了一个JSON数据。为什么所有的值都没有设置为ListItem。

test_layout

<?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="match_parent"
    android:orientation="vertical">
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="#2E353D"
        android:orientation="vertical">

        <LinearLayout
            android:layout_width="wrap_content"
            android:layout_height="40dp"
            android:layout_gravity="center_horizontal"
            android:orientation="horizontal">

            <ImageView
                android:layout_width="30dp"
                android:layout_height="match_parent"
                android:padding="3dp" />

            <TextView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_gravity="center_vertical"
                android:layout_marginLeft="8dp"
                android:text="Class Schedule"
                android:textColor="#fff"
                android:textSize="17dp"
                android:textStyle="bold" />

        </LinearLayout>
    </LinearLayout>


    <LinearLayout
        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">

            <LinearLayout
                android:id="@+id/sunday"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="#008b8b"
                android:orientation="vertical">

                <TextView
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_gravity="center_horizontal"
                    android:padding="6dp"
                    android:text="SUNDAY"
                    android:textColor="#fff"
                    android:textStyle="bold" />
            </LinearLayout>


            <LinearLayout
                android:id="@+id/sunday_class"
                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:background="#A4ACB0"
                    android:orientation="horizontal"
                    android:padding="5dp">

                    <TextView
                        android:layout_width="0dp"
                        android:layout_height="match_parent"
                        android:layout_weight="1"
                        android:gravity="center_horizontal"
                        android:padding="5dp"
                        android:text="Subject"
                        android:textSize="12dp"
                        android:textStyle="bold" />

                    <TextView
                        android:layout_width="0dp"
                        android:layout_height="match_parent"
                        android:layout_weight="1"
                        android:gravity="center_horizontal"
                        android:padding="5dp"
                        android:text="Teacher"
                        android:textSize="12dp"
                        android:textStyle="bold" />

                    <TextView
                        android:layout_width="0dp"
                        android:layout_height="match_parent"
                        android:layout_weight="1"
                        android:gravity="center_horizontal"
                        android:padding="5dp"
                        android:text="Time"
                        android:textSize="12dp"
                        android:textStyle="bold" />
                </LinearLayout>

                <ListView
                    android:id="@+id/list_class_schedule"
                    android:layout_width="match_parent"
                    android:layout_height="fill_parent" />

                <View
                    android:layout_width="match_parent"
                    android:layout_height="1dp"
                    android:background="#C5CED1" />
            </LinearLayout>

        </LinearLayout>
    </LinearLayout>
</LinearLayout>

FragmentClassTest

public class FragmentClassTest extends Fragment implements View.OnClickListener {


    LinearLayout sunday, sundaySchedule, monday, mondayClass, tuesday, tuesdayClass, wednesday, wednesdayClass, thrusday, thrusdayClass, friday, fridayClass;

    public static final String Navigation_URL = "http://192.168.100.5:84/api/employeeApi/timeTableByClass";
    String master_id;

    String day;


    ListView listViewStudentClass;


    String access_token;
    String TeacherName, SubjectName, Time;


    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {

        View view = inflater.inflate(R.layout.test_layout, container, false);
        setHasOptionsMenu(true);

        sunday = (LinearLayout) view.findViewById(R.id.sunday);
        monday = (LinearLayout) view.findViewById(R.id.monday);
        tuesday = (LinearLayout) view.findViewById(R.id.tuesday);
        wednesday = (LinearLayout) view.findViewById(R.id.wednesday);
        thrusday = (LinearLayout) view.findViewById(R.id.thrusday);
        friday = (LinearLayout) view.findViewById(R.id.friday);


        sundaySchedule = (LinearLayout) view.findViewById(R.id.sunday_class);
        mondayClass = (LinearLayout) view.findViewById(R.id.monday_class);
        tuesdayClass = (LinearLayout) view.findViewById(R.id.tuesday_class);
        wednesdayClass = (LinearLayout) view.findViewById(R.id.wednesday_class);
        thrusdayClass = (LinearLayout) view.findViewById(R.id.thrusday_class);
        fridayClass = (LinearLayout) view.findViewById(R.id.friday_class);


        listViewStudentClass = (ListView) view.findViewById(R.id.list_class_schedule);


        sundaySchedule.setVisibility(View.VISIBLE);
        mondayClass.setVisibility(View.GONE);
        tuesdayClass.setVisibility(View.GONE);
        wednesdayClass.setVisibility(View.GONE);
        thrusdayClass.setVisibility(View.GONE);
        fridayClass.setVisibility(View.GONE);


        sunday.setOnClickListener(this);
        monday.setOnClickListener(this);
        tuesday.setOnClickListener(this);
        wednesday.setOnClickListener(this);
        thrusday.setOnClickListener(this);
        friday.setOnClickListener(this);


        SessionManagement session = new SessionManagement(getContext());
        session.checkLogin();
        master_id = session.getMasterId();
        access_token = session.getAccesstToken();


        makeJsonObjectRequest();
        return view;
    }

    ClassScheduleStudent classScheduleStudent;


    private void makeJsonObjectRequest() {

        RequestQueue requestQueue = Volley.newRequestQueue(getContext());
        String URL = Navigation_URL + "?Sid=" + master_id;
        System.out.println(URL);

        StringRequest stringRequest = new StringRequest(Request.Method.GET, URL,
                new Response.Listener<String>() {
                    @Override
                    public void onResponse(String response) {
                        try {


                            ArrayList<ClassScheduleStudent> student_list_class_schedule = new ArrayList<>();
                            JSONArray jArray = new JSONArray(response);


                            //  studentFeeInformation = new StudentFeeInformation(response);
                            for (int i = 0; i < jArray.length(); i++) {


                                JSONObject jsonObject = jArray.getJSONObject(i);
                                day = jsonObject.getString("DayOfTheWeek");


                                if (day.equals("1")) {
                                    JSONObject studentDetails_obj = jsonObject.getJSONObject("teachers");
                                    JSONObject studentDetails_course = jsonObject.getJSONObject("courses");
                                    SubjectName = (String) studentDetails_course.get("CourseName");
                                    TeacherName = studentDetails_obj.getString("NAME");
                                    Time = jsonObject.getString("StartTime");

                                    // Log.d("ListData", "@@@ TeacherName:" + TeacherName);
                                    student_list_class_schedule.add(new ClassScheduleStudent(SubjectName, TeacherName, Time));
                                }

                            }

                            //  Log.d("ListData", "@@@ student_list_class_schedule size :" + student_list_class_schedule.size());
                            ClassScheduleStudentAdapter classScheduleStudentAdatpter = new ClassScheduleStudentAdapter(getActivity(), student_list_class_schedule);
                            listViewStudentClass.setAdapter(classScheduleStudentAdatpter);


                        } catch (JSONException e) {
                            Toast.makeText(getContext(), "Fetch failed!", Toast.LENGTH_SHORT).show();
                            e.printStackTrace();
                        }
                    }

                }, new Response.ErrorListener() {
            @Override
            public void onErrorResponse(VolleyError error) {
                Toast.makeText(getContext(), error.toString(), Toast.LENGTH_LONG).show();
            }
        }) {

            @Override
            public Map<String, String> getHeaders() throws AuthFailureError {
                Map<String, String> headers = new HashMap<String, String>();
                headers.put("Authorization", "Bearer " + access_token);
                headers.put("Content-Type", "application/x-www-form-urlencoded");
                return headers;
            }
/*
            @Override
            protected Map<String, String> getParams() throws com.android.volley.AuthFailureError {
                Map<String, String> map = new HashMap<String, String>();

                map.put("id", master_id);
                map.put("accessID", accessID);
                map.put("currentUser", master_id);
                return map;

            } */
        };


        requestQueue.add(stringRequest);

    }


    @Override
    public void onClick(View v) {
        switch (v.getId()) {
            case R.id.sunday:
                if (sundaySchedule.getVisibility() == View.GONE) {
                    sundaySchedule.setVisibility(View.VISIBLE);
                } else if (sundaySchedule.getVisibility() == View.VISIBLE) {
                    sundaySchedule.setVisibility(View.GONE);
                }
                break;
            case R.id.monday:
                if (mondayClass.getVisibility() == View.GONE) {
                    mondayClass.setVisibility(View.VISIBLE);
                } else if (mondayClass.getVisibility() == View.VISIBLE) {
                    mondayClass.setVisibility(View.GONE);
                }
                break;
            case R.id.tuesday:
                if (tuesdayClass.getVisibility() == View.GONE) {
                    tuesdayClass.setVisibility(View.VISIBLE);
                } else if (tuesdayClass.getVisibility() == View.VISIBLE) {
                    tuesdayClass.setVisibility(View.GONE);
                }
                break;
            case R.id.wednesday:
                if (wednesdayClass.getVisibility() == View.GONE) {
                    wednesdayClass.setVisibility(View.VISIBLE);
                } else if (wednesdayClass.getVisibility() == View.VISIBLE) {
                    wednesdayClass.setVisibility(View.GONE);
                }
                break;
            case R.id.thrusday:
                if (thrusdayClass.getVisibility() == View.GONE) {
                    thrusdayClass.setVisibility(View.VISIBLE);
                } else if (thrusdayClass.getVisibility() == View.VISIBLE) {
                    thrusdayClass.setVisibility(View.GONE);
                }
                break;
            case R.id.friday:
                if (fridayClass.getVisibility() == View.GONE) {
                    fridayClass.setVisibility(View.VISIBLE);
                } else if (fridayClass.getVisibility() == View.VISIBLE) {
                    fridayClass.setVisibility(View.GONE);
                }
                break;
        }
    }


    @Override
    public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
        // TODO Auto-generated method stub
        super.onCreateOptionsMenu(menu, inflater);
        inflater.inflate(R.menu.dashboard, menu);
    }

}

ClassScheduleStudentAdapter

public class ClassScheduleStudentAdapter extends BaseAdapter {


    Context mContext;

    ArrayList<ClassScheduleStudent> student_class_schedule=null;
    String TAG = "HomeTab_adapter";

    public ClassScheduleStudentAdapter(Context mContext, ArrayList<ClassScheduleStudent> student_class_schedule) {
        super();
        this.mContext = mContext;
        this.student_class_schedule = student_class_schedule;
    }

    @Override
    public int getCount() {
        System.out.println(student_class_schedule.size());
        return student_class_schedule.size();

    }

    @Override
    public Object getItem(int position) {
        return student_class_schedule.get(position);
        // return arg0;
    }

    @Override
    public long getItemId(int position) {
        return position;
    }

    @Override
    public View getView(final int postion, View convertView, ViewGroup parent) {
       // final ClassScheduleStudentAdapter.Holder viewHolder;
        final Holder viewHolder;

        if (convertView == null) {
            // inflate the layout
            LayoutInflater inflater = (LayoutInflater) mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            // LayoutInflater inflater = LayoutInflater.from(parent.getContext());
            convertView = inflater.inflate(R.layout.class_schedule_listitem_student, parent, false);

            // well set up the ViewHolder
          //  viewHolder = new ClassScheduleStudentAdapter.Holder();
            viewHolder=new Holder();

            viewHolder.student_profile_class_schedule_Subject = (TextView) convertView.findViewById(R.id.student_profile_subject);
            viewHolder.student_profile_class_schedule_TeacherName = (TextView) convertView.findViewById(R.id.student_profile_teacherName);
            viewHolder.student_profile_class_schedule_Time = (TextView) convertView.findViewById(R.id.student_profile_Time);
            convertView.setTag(viewHolder);


        } else {
            // we've just avoided calling findViewById() on resource everytime
            // just use the viewHolder
          //  viewHolder = (ClassScheduleStudentAdapter.Holder) convertView.getTag();
            viewHolder=(Holder)convertView.getTag();
        }
        Log.d(TAG,"@@ postion:"+postion+" getTeacherName"+student_class_schedule.get(postion).getTeacherName());
        viewHolder.student_profile_class_schedule_Subject.setText(student_class_schedule.get(postion).getSubject());
        viewHolder.student_profile_class_schedule_TeacherName.setText(student_class_schedule.get(postion).getTeacherName());
        viewHolder.student_profile_class_schedule_Time.setText(student_class_schedule.get(postion).getTime());


       // convertView.setTag(viewHolder);
        return convertView;
    }

    class Holder {


        TextView student_profile_class_schedule_Subject;
        TextView student_profile_class_schedule_TeacherName;
        TextView student_profile_class_schedule_Time;


    }




}

确切的问题是什么？我几天都无法解决。

注意更新的解决方案以前我在ScrollVIew中有ListView这是仅显示一个Item的主要原因。所以从不包括listView里面的listView，listView是可自动滚动的需要scrollView

Answer 1

如果convertView.setTag(viewHolder);

，请在{p>内设置(convertView == null)

检查日志的位置值

@Override
public View getView(final int postion, View convertView, ViewGroup parent) {
    final Holder viewHolder;
    if (convertView == null) {
        // inflate the layout
        LayoutInflater inflater = (LayoutInflater) mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        // LayoutInflater inflater = LayoutInflater.from(parent.getContext());
        convertView = inflater.inflate(R.layout.class_schedule_listitem_student, parent, false);

        // well set up the ViewHolder
        viewHolder = new Holder();
        viewHolder.student_profile_class_schedule_Subject = (TextView) convertView.findViewById(R.id.student_profile_subject);
        viewHolder.student_profile_class_schedule_TeacherName = (TextView) convertView.findViewById(R.id.student_profile_teacherName);
        viewHolder.student_profile_class_schedule_Time = (TextView) convertView.findViewById(R.id.student_profile_Time);
        convertView.setTag(viewHolder);//add set tag here

    } else {
        // we've just avoided calling findViewById() on resource everytime
        // just use the viewHolder
        viewHolder = (Holder) convertView.getTag();
    }

    Log.d(TAG,"@@ postion:"+postion+" getTeacherName"+student_class_schedule.get(postion).getTeacherName());

    viewHolder.student_profile_class_schedule_Subject.setText(student_class_schedule.get(postion).getSubject());
    viewHolder.student_profile_class_schedule_TeacherName.setText(student_class_schedule.get(postion).getTeacherName());
    viewHolder.student_profile_class_schedule_Time.setText(student_class_schedule.get(postion).getTime());

    return convertView;
}

makeJsonObjectRequest：

private void makeJsonObjectRequest() {

    RequestQueue requestQueue = Volley.newRequestQueue(getContext());
    String URL = Navigation_URL + "?Sid=" + master_id;
    System.out.println(URL);

    StringRequest stringRequest = new StringRequest(Request.Method.GET, URL,
            new Response.Listener<String>() {
                @Override
                public void onResponse(String response) {
                    try {
                        ArrayList<ClassScheduleStudent> student_list_class_schedule = new ArrayList<>();
                        JSONArray jArray = new JSONArray(response);

                        //  studentFeeInformation = new StudentFeeInformation(response);
                        for (int i = 0; i < jArray.length(); i++) {

                            JSONObject jsonObject = jArray.getJSONObject(i);
                            day = jsonObject.getString("DayOfTheWeek");
                            if(day.equals("1"))
                            {
                                JSONObject studentDetails_obj = jsonObject.getJSONObject("teachers");
                                JSONObject studentDetails_course = jsonObject.getJSONObject("courses");
                                SubjectName = (String) studentDetails_course.get("CourseName");
                                TeacherName = studentDetails_obj.getString("NAME");
                                Time = jsonObject.getString("StartTime");

                                Log.d("ListData", "@@@ TeacherName:"+TeacherName);
                                student_list_class_schedule.add(new ClassScheduleStudent(SubjectName, TeacherName, Time));
                            }


                        }
                        Log.d("ListData", "@@@ student_list_class_schedule size :"+student_list_class_schedule.size());
                        ClassScheduleStudentAdapter classScheduleStudentAdatpter = new ClassScheduleStudentAdapter(getActivity(), student_list_class_schedule);
                        listViewStudentClass.setAdapter(classScheduleStudentAdatpter);

                    } catch (JSONException e) {
                        Toast.makeText(getContext(), "Fetch failed!", Toast.LENGTH_SHORT).show();
                        e.printStackTrace();
                    }
                }

            }, new Response.ErrorListener() {
        @Override
        public void onErrorResponse(VolleyError error) {
            Toast.makeText(getContext(), error.toString(), Toast.LENGTH_LONG).show();
        }
    }) {

        @Override
        public Map<String, String> getHeaders() throws AuthFailureError {
            Map<String, String> headers = new HashMap<String, String>();
            headers.put("Authorization", "Bearer " + access_token);
            headers.put("Content-Type", "application/x-www-form-urlencoded");
            return headers;
        }
        /*
        @Override
        protected Map<String, String> getParams() throws com.android.volley.AuthFailureError {
            Map<String, String> map = new HashMap<String, String>();

            map.put("id", master_id);
            map.put("accessID", accessID);
            map.put("currentUser", master_id);
            return map;

        } */
    };
    requestQueue.add(stringRequest);
}

适配器布局：

<TextView id="@+id/tv_Days">//For days sunday, monday ...
<RelativeLayout id="@+id/Layout1">//for lable subject,teacher...
<RelativeLayout id="@+id/Layout2">//for display all lable values

模特课程：

private day, subject,teacher;

在getview适配器

中

private String previous_day="";
if(previous_day.equals("") || previous_day!=student_class_schedule.get(postion).getDay())
{

    tv_Days.setVisibility(View.VISIBLE)
    Layout1.setVisibility(View.VISIBLE)
}
else
{
    tv_Days.setVisibility(View.GONE)
    Layout1.setVisibility(View.GONE)
}

.
.
//set other values

Answer 2

在致电makeJsonObjectRequest()

之前移动此行

ArrayList<ClassScheduleStudent> student_list_class_schedule = new ArrayList<>();
    ClassScheduleStudentAdapter customFeeListStudentAdapter = new ClassScheduleStudentAdapter(getActivity(), student_list_student_fee);
                                    listViewStudentClass.setAdapter(customFeeListStudentAdapter);

从响应中移除ArrayList<ClassScheduleStudent> student_list_class_schedule = new ArrayList<>();这一行。当你在for循环中获得完整的数组列表时，然后调用

classScheduleStudentAdatpter.setList(student_list_class_schedule)
classScheduleStudentAdatpter.notifyDatasetChanged();

内部适配器，

private void setList( ArrayList<ClassScheduleStudent> student_class_schedule){
this.student_class_schedule = student_class_schedule;
}

Answer 3

可能是问题是因为您实施了错误的视图持有者模式。

您如何实施

if(convertview == null){
 ....
 ....
}else{
 viewHolder = (ViewHolderItem) convertView.getTag();
}
convertView.setTag(viewHolder);

但它应该像

if(convertview == null){
 ....
 ....
 convertView.setTag(viewHolder);
}else{
 viewHolder = (ViewHolderItem) convertView.getTag();
}

所以现在替换适配器的 getView 方法

@Override
public View getView(final int postion, View convertView, ViewGroup parent) {
    final ClassScheduleStudentAdapter.Holder viewHolder;
    if (convertView == null) {
        // inflate the layout
        LayoutInflater inflater = (LayoutInflater) mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        // LayoutInflater inflater = LayoutInflater.from(parent.getContext());
        convertView = inflater.inflate(R.layout.class_schedule_listitem_student, parent, false);

        // well set up the ViewHolder
        viewHolder = new ClassScheduleStudentAdapter.Holder();
        viewHolder.student_profile_class_schedule_Subject = (TextView) convertView.findViewById(R.id.student_profile_subject);
        viewHolder.student_profile_class_schedule_TeacherName = (TextView) convertView.findViewById(R.id.student_profile_teacherName);
        viewHolder.student_profile_class_schedule_Time = (TextView) convertView.findViewById(R.id.student_profile_Time);

        convertView.setTag(viewHolder);

    } else {
        // we've just avoided calling findViewById() on resource everytime
        // just use the viewHolder
         viewHolder = (Holder) convertView.getTag();
    }

    viewHolder.student_profile_class_schedule_Subject.setText(student_class_schedule.get(postion).getSubject());
    viewHolder.student_profile_class_schedule_TeacherName.setText(student_class_schedule.get(postion).getTeacherName());
    viewHolder.student_profile_class_schedule_Time.setText(student_class_schedule.get(postion).getTime());


    return convertView;
}

ListView只显示一个项目？

3 个答案: