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问题描述

 公共类BriefFragmentActivity扩展片段
    {
        公共BriefFragmentActivity()
        {
        }
        公共静态最后弦乐ARG_SECTION_NUMBER =SECTION_NUMBER;
        字符串getParameter_Url =参数/ getParameters
        微调spinnerSystemType;
        ArrayList的<串GT; systemTypeArrayList;
        DataBaseAdapter dataBaseAdapterInstance;
        @覆盖
        公共查看onCreateView(LayoutInflater充气器,容器的ViewGroup,
                捆绑savedInstanceState){
        视图V = inflater.inflate(R.layout.brief_fragment_view,NULL);
        getAllSpinnerValues​​();
        spinnerSystemType =(微调)v.findViewById(R.id.spinner_systemtype);
        返回伏;
 }    私人无效getAllSpinnerValues​​()
   {
    systemTypeArrayList =新的ArrayList<串GT;();
    dataBaseAdapterInstance =新DataBaseAdapter(getActivity()getApplicationContext());
    dataBaseAdapterInstance.openToRead();
    清单<参数> PARAMETERLIST =新的ArrayList<参数>();
    PARAMETERLIST = dataBaseAdapterInstance.getParameterList();
    对于(参数p:PARAMETERLIST)
{
    Log.i(参数列表,+ p.getId()+现金code+ p.getCash code()+.....+ p.getParamType()) ;
    如果(p.getParamType()。修剪()。的toString()。equalsIgnoreCase(系统类型))
{
   Log.i(系统类型,字符串比较块);
   systemTypeArrayList.add(p.getParamDescription()修剪()的toString());
   Log.i(systemTypeArrayList:,+ systemTypeArrayList); ** //从bean类获得该线路上正确的数据..... **
// **错误是试图添加此ArrayList到ArrayAdapter时**
 ArrayAdapter<串GT; adapterSystemType =新ArrayAdapter<串GT;(getActivity(),R.layout.custom_spinner,systemTypeArrayList);adapterSystemType.setDropDownViewResource(R.layout.custom_spinner_item_list);
 spinnerSystemType.setAdapter(adapterSystemType);
 adapterSystemType.notifyDataSetChanged();}
 其他
   {
 Log.i(价值观,+ p.getParamType());
   }
   }
  dataBaseAdapterInstance.close();
  }
  }

请忽略的错误{}
           我认为有上下文所以它给我error.Error从这个LOC开始的一些错误:

ArrayAdapter adapterSystemType =新ArrayAdapter(getActivity(),R.layout.custom_spinner,systemTypeArrayList);
      这之前的一切工作正常。
这里是logcat的:

  4月12日至20日:48:26.115:E / AndroidRuntime(20657):致命异常:主要
四月12日至20日:48:26.115:E / AndroidRuntime(20657):了java.lang.RuntimeException:无法启动活动ComponentInfo {com.survey.management.activity / com.survey.management.activity.FragmentMainActivity}:显示java.lang.NullPointerException
四月12日至20日:48:26.115:E / AndroidRuntime(20657):在android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2100)四月12日至20日:48:26.115:E / AndroidRuntime(20657):在android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2125)四月12日至20日:48:26.115:E / AndroidRuntime(20657):在android.app.ActivityThread.access $ 600(ActivityThread.java:140)四月12日至20日:48:26.115:E / AndroidRuntime(20657):在android.app.ActivityThread $ H.handleMessage(ActivityThread.java:1227)四月12日至20日:48:26.115:E / AndroidRuntime(20657):在android.os.Handler.dispatchMessage(Handler.java:99)四月12日至20日:48:26.115:E / AndroidRuntime(20657):在android.os.Looper.loop(Looper.java:137)四月12日至20日:48:26.115:E / AndroidRuntime(20657):在android.app.ActivityThread.main(ActivityThread.java:4898)四月12日至20日:48:26.115:E / AndroidRuntime(20657):在java.lang.reflect.Method.invokeNative(本机方法)四月12日至20日:48:26.115:E / AndroidRuntime(20657):在java.lang.reflect.Method.invoke(Method.java:511)四月12日至20日:48:26.115:E / AndroidRuntime(20657):在com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run(ZygoteInit.java:1006)四月12日至20日:48:26.115:E / AndroidRuntime(20657):在com.android.internal.os.ZygoteInit.main(ZygoteInit.java:773)四月12日至20日:48:26.115:E / AndroidRuntime(20657):在dalvik.system.NativeStart.main(本机方法)四月12日至20日:48:26.115:E / AndroidRuntime(20657):致:显示java.lang.NullPointerException四月12日至20日:48:26.115:E / AndroidRuntime(20657):在com.survey.management.activity.BriefFragmentActivity.getAllSpinnerValues(BriefFragmentActivity.java:701)四月12日至20日:48:26.115:E / AndroidRuntime(20657):在com.survey.management.activity.BriefFragmentActivity.onCreateView(BriefFragmentActivity.java:67)四月12日至20日:48:26.115:E / AndroidRuntime(20657):在android.support.v4.app.Fragment.performCreateView(Fragment.java:1460)四月12日至20日:48:26.115:E / AndroidRuntime(20657):在android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:911)四月12日至20日:48:26.115:E / AndroidRuntime(20657):在android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1088)四月12日至20日:48:26.115:E / AndroidRuntime(20657):在android.support.v4.app.BackStackRecord.run(BackStackRecord.java:682)四月12日至20日:48:26.115:E / AndroidRuntime(20657):在android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1444)四月12日至20日:48:26.115:E / AndroidRuntime(20657):在android.support.v4.app.FragmentActivity.onStart(FragmentActivity.java:551)四月12日至20日:48:26.115:E / AndroidRuntime(20657):在android.app.Instrumentation.callActivityOnStart(Instrumentation.java:1167)四月12日至20日:48:26.115:E / AndroidRuntime(20657):在android.app.Activity.performStart(Activity.java:5216)四月12日至20日:48:26.115:E / AndroidRuntime(20657):在android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2073)四月12日至20日:48:26.115:E / AndroidRuntime(20657):... 11个


解决方案

使用

  dataBaseAdapterInstance =新DataBaseAdapter(getActivity());

还有 spinnerSystemType 未初始化

 视图V = inflater.inflate(R.layout.brief_fragment_view,NULL);
spinnerSystemType =(微调)v.findViewById(R.id.spinner1);
//确保ID spinner1是正确的
    public class BriefFragmentActivity extends Fragment
    {
        public BriefFragmentActivity()
        {
        }
        public static final String ARG_SECTION_NUMBER = "section_number";
        String getParameter_Url = "parameters/getParameters";
        Spinner spinnerSystemType;
        ArrayList<String> systemTypeArrayList;
        DataBaseAdapter dataBaseAdapterInstance;
        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container,
                Bundle savedInstanceState) {
        View v = inflater.inflate(R.layout.brief_fragment_view, null);
        getAllSpinnerValues();
        spinnerSystemType = (Spinner) v.findViewById(R.id.spinner_systemtype);
        return v;
 }

    private void getAllSpinnerValues()
   {
    systemTypeArrayList = new ArrayList<String>();
    dataBaseAdapterInstance = new DataBaseAdapter(getActivity().getApplicationContext());
    dataBaseAdapterInstance.openToRead();
    List<Parameters> parameterList = new ArrayList<Parameters>(); 
    parameterList = dataBaseAdapterInstance.getParameterList();
    for (Parameters p : parameterList) 
{
    Log.i("parameter list",""+p.getId()  + "cash code" + p.getCashCode()  +"....." + p.getParamType());
    if(p.getParamType().trim().toString().equalsIgnoreCase("system type"))
{
   Log.i("system type","string comparison block");
   systemTypeArrayList.add(p.getParamDescription().trim().toString());
   Log.i("systemTypeArrayList:",""+systemTypeArrayList);  **// getting correct data on this line from bean class.....**
//**Error is when trying to add this arrayList to ArrayAdapter** 
 ArrayAdapter<String> adapterSystemType = new ArrayAdapter<String>(getActivity(),R.layout.custom_spinner,systemTypeArrayList);

adapterSystemType.setDropDownViewResource(R.layout.custom_spinner_item_list);
 spinnerSystemType.setAdapter(adapterSystemType);
 adapterSystemType.notifyDataSetChanged();

}
 else
   {
 Log.i("values",""+p.getParamType());
   }
   } 
  dataBaseAdapterInstance.close();
  }
  }

please ignore mistake of { } i think there is some mistake of Context thats why its giving me error.Error starts from this LOC:

ArrayAdapter adapterSystemType = new ArrayAdapter(getActivity(),R.layout.custom_spinner,systemTypeArrayList); before this everything working fine.Here is the Logcat:

12-20 04:48:26.115: E/AndroidRuntime(20657): FATAL EXCEPTION: main
12-20 04:48:26.115: E/AndroidRuntime(20657): java.lang.RuntimeException: Unable to start activity 

ComponentInfo{com.survey.management.activity/com.survey.management.activity.FragmentMainActivity}: java.lang.NullPointerException
12-20 04:48:26.115: E/AndroidRuntime(20657):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2100)

12-20 04:48:26.115: E/AndroidRuntime(20657):    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2125)

12-20 04:48:26.115: E/AndroidRuntime(20657):    at android.app.ActivityThread.access$600(ActivityThread.java:140)

12-20 04:48:26.115: E/AndroidRuntime(20657):    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1227)

12-20 04:48:26.115: E/AndroidRuntime(20657):    at android.os.Handler.dispatchMessage(Handler.java:99)

12-20 04:48:26.115: E/AndroidRuntime(20657):    at android.os.Looper.loop(Looper.java:137)

12-20 04:48:26.115: E/AndroidRuntime(20657):    at android.app.ActivityThread.main(ActivityThread.java:4898)

12-20 04:48:26.115: E/AndroidRuntime(20657):    at java.lang.reflect.Method.invokeNative(Native Method)

12-20 04:48:26.115: E/AndroidRuntime(20657):    at java.lang.reflect.Method.invoke(Method.java:511)

12-20 04:48:26.115: E/AndroidRuntime(20657):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1006)

12-20 04:48:26.115: E/AndroidRuntime(20657):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:773)

12-20 04:48:26.115: E/AndroidRuntime(20657):    at dalvik.system.NativeStart.main(Native Method)

12-20 04:48:26.115: E/AndroidRuntime(20657): Caused by: java.lang.NullPointerException

12-20 04:48:26.115: E/AndroidRuntime(20657):    at com.survey.management.activity.BriefFragmentActivity.getAllSpinnerValues(BriefFragmentActivity.java:701)

12-20 04:48:26.115: E/AndroidRuntime(20657):    at com.survey.management.activity.BriefFragmentActivity.onCreateView(BriefFragmentActivity.java:67)

12-20 04:48:26.115: E/AndroidRuntime(20657):    at android.support.v4.app.Fragment.performCreateView(Fragment.java:1460)

12-20 04:48:26.115: E/AndroidRuntime(20657):    at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:911)

12-20 04:48:26.115: E/AndroidRuntime(20657):    at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1088)

12-20 04:48:26.115: E/AndroidRuntime(20657):    at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:682)

12-20 04:48:26.115: E/AndroidRuntime(20657):    at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1444)

12-20 04:48:26.115: E/AndroidRuntime(20657):    at android.support.v4.app.FragmentActivity.onStart(FragmentActivity.java:551)

12-20 04:48:26.115: E/AndroidRuntime(20657):    at android.app.Instrumentation.callActivityOnStart(Instrumentation.java:1167)

12-20 04:48:26.115: E/AndroidRuntime(20657):    at android.app.Activity.performStart(Activity.java:5216)

12-20 04:48:26.115: E/AndroidRuntime(20657):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2073)

12-20 04:48:26.115: E/AndroidRuntime(20657):    ... 11 more
解决方案

Use

dataBaseAdapterInstance = new DataBaseAdapter(getActivity());

Also spinnerSystemType is not initialized

View v = inflater.inflate(R.layout.brief_fragment_view, null);
spinnerSystemType =(Spinner)v.findViewById(R.id.spinner1);
// make sure the id spinner1 is right

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10-16 16:31