JSON 对象到 Spinner 崩溃应用程序

Question

我有以下问题。 一个日期选择器，我在其中选择一个日期，这将与用户名一起放入一个数组中。该数组用于通过使用 Parser 中的 GetMemberPatrolStartTimes 获取用户开始时间。这将返回 JSON 对象，然后将其发送到填充的巡逻历史记录一个微调器。

我可以看到微调器已填充，但只要我单击将微调器放下，我就会收到文件中附加的错误。

现在我可以读取错误，但用它来解决我无法正确解决的问题。

感谢所有帮助、指导和任何建设性的批评

错误：java.lang.NullPointerException：尝试在空对象引用上调用虚拟方法“java.lang.String java.lang.Object.toString()”

这被 UncaughtException 方法捕获 eyeWatchApi.java

public JSONObject GetMemberPatrolStartTimes(ArrayList<String> details)throws Exception {
    JSONObject result = null;
    JSONObject o = new JSONObject();
    JSONObject p = new JSONObject();
    o.put("interface","eyeWatchApi");
    o.put("method", "GetMemberPatrolStartTimes");
    p.put("details",mapObject(details));
    o.put("parameters", p);
    String s = o.toString();
    String r = load(s);
    result = new JSONObject(r);
    return result;
}

Parser.java

public Object GetPatrolHistoryStartTimes(JSONObject object){
    String[] id_Array;
    String[] time_Array;

    try{
        JSONArray a = object.getJSONArray("Value");

        id_Array = new String[a.length()];
        time_Array = new String[a.length()];

        for (int i = 0; i < a.length(); i++) {
            JSONObject b = a.getJSONObject(i);

            id_Array[i]=b.getString("startID");
            time_Array[i]=b.getString("startTime");
            return new Object[]{id_Array,time_Array};
        }
    }catch (JSONException e){
      return e;
    }catch (Exception e){
        return e;
    }
    return null;
}

Patrol_History.java

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

    View view = inflater.inflate(R.layout.patrol_history,container,false);

        timeSpinner = (Spinner) view.findViewById(R.id.TimeSpinner);

        timeSpinner.setOnItemSelectedListener(this);
}

@Override
public void onClick(View view)
{
    switch(view.getId())
    {
        case R.id.load_polly_btn :
        {
            drawpoliline();
            break;
        }
        case R.id.select_date_txt :
        {
            Date_Pick_Dialog picker = new Date_Pick_Dialog();
            picker.setDatePickerDialogFragmentEvents(this);
            picker.show(getFragmentManager(), "datePicker");
            break;
        }
        default:
        {
            break;
        }
    }
}

@Override
public void onDateSelected(String _date) {

        patrolHistoryManager = new PatrolHistoryManager(getActivity());
        patrolHistoryManager.setDate(_date);
        selectDate_tv.setText(_date);
        date = _date;
       new AsyncSendDetails().execute(date);


    //new AsyncGetAvailibleSlots().execute(_date);
}

public class AsyncSendDetails extends AsyncTask<String, Void, Object[]> {

    @Override
    protected Object[] doInBackground(String... params) {


        eyeWatchApi api = new eyeWatchApi();
        Parser parser = new Parser();
        detailsList = new ArrayList<String>();
        detailsList.add(userName);
        detailsList.add(params[0]);

        Object[] ob = new Object[0];
        try {
            ob = (Object[]) parser.GetPatrolHistoryStartTimes(api.GetMemberPatrolStartTimes(detailsList));
        } catch (Exception e) {
            e.printStackTrace();
        }
        return ob;

    }

    @Override
    protected void onPostExecute(Object[] ob) {
        if(ob != null)
        {
        timeID = (String[]) ob[0];
        times = (String[]) ob[1];


            ArrayAdapter<String> dataAdapter = new ArrayAdapter<String>(getActivity(), R.layout.countries_spinner_item, times);
            dataAdapter.setDropDownViewResource(R.layout.countries_spinner_item_droplist);
            timeSpinner.setAdapter(dataAdapter);
        }
        else
        {
            Toast.makeText(getActivity(),"No Slots Available",Toast.LENGTH_LONG).show();
        }

    }
}

布局文件

<RelativeLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="@color/black">
    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"

        android:hint="Select Date"
        android:textAlignment="center"
        android:textColor="#d32f2f"
        android:cursorVisible="false"
        android:shadowColor="@color/black"
        android:id="@+id/select_date_txt"
        android:layout_gravity="top|right"
        android:text="02/05/2016"
        android:paddingRight="15dp"
        android:paddingBottom="10dp"
        android:paddingTop="10dp"

        android:layout_alignParentTop="true"
        android:layout_centerHorizontal="true" />

    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="1dp"
        android:background="@color/white"
        android:layout_below="@+id/select_date_txt"
        android:layout_alignParentLeft="true"
        android:layout_alignParentStart="true"
        android:id="@+id/relativeLayout2" />


    <Spinner
        android:id="@+id/TimeSpinner"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:textColor="#d32f2f"
        android:layout_below="@+id/select_date_txt"
        android:layout_alignParentLeft="true"
        android:layout_alignParentStart="true">


    </Spinner>
    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="2dp"
        android:paddingBottom="2dp"
        android:background="@color/primary"
        android:id="@+id/relativeLayout"
        android:layout_below="@+id/TimeSpinner"
        android:layout_alignParentLeft="true"
        android:layout_alignParentStart="true" />
</RelativeLayout>

<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_below="@+id/relativeLayout">
<fragment
    android:id="@+id/map"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    class="com.google.android.gms.maps.SupportMapFragment"
    android:layout_weight="0.73"
    android:layout_alignParentLeft="true"
    android:layout_alignParentStart="true">



</fragment>
<android.support.v7.widget.AppCompatButton
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Load Lines"
    android:id="@+id/load_polly_btn"
    android:layout_alignParentBottom="true"
    android:layout_alignParentLeft="true"
    android:layout_alignParentStart="true" />

</RelativeLayout>

</LinearLayout>

Answer 1

经过将近一周的努力，我刚刚找到了答案，所以我将把它放在这里，让大家看看是否需要它

**Parser.java**

public Object GetPatrolHistoryStartTimes(JSONObject object){
String[] id_Array;
String[] time_Array;

try{
    JSONArray a = object.getJSONArray("Value");

    id_Array = new String[a.length()];
    time_Array = new String[a.length()];

    for (int i = 0; i < a.length(); i++) {
        JSONObject b = a.getJSONObject(i);

        id_Array[i]=b.getString("startID");
        time_Array[i]=b.getString("startTime");
       }
return new Object[]{id_Array,time_Array};
}catch (JSONException e){
  return e;
}catch (Exception e){
    return e;
}
return null;
}

问题是我返回的对象不应该在 for 语句中，而是在它之后，在循环完成之后