获取电池信息时的Android错误（在片段中）

Question

我的应用程序有几个操作栏选项卡，这是片段之一。它应该显示关于电池的一些信息。这些错误导航应用的bit.Please解释后会出现什么问题引起的，应该怎么做才能解决这个问题

下面是从logcat的错误：

05-15 07:24:30.809: E/AndroidRuntime(25883): FATAL EXCEPTION: main 
05-15 07:24:30.809: E/AndroidRuntime(25883): java.lang.RuntimeException: Error receiving broadcast Intent { act=android.intent.action.BATTERY_CHANGED flg=0x60000010 (has extras) } in com.example.mytaskmanager.Battery$1@4185ea78 
05-15 07:24:30.809: E/AndroidRuntime(25883):  at android.app.LoadedApk$ReceiverDispatcher$Args.run(LoadedApk.java:755) 
05-15 07:24:30.809: E/AndroidRuntime(25883):  at android.os.Handler.handleCallback(Handler.java:605) 
05-15 07:24:30.809: E/AndroidRuntime(25883):  at android.os.Handler.dispatchMessage(Handler.java:92) 
05-15 07:24:30.809: E/AndroidRuntime(25883):  at android.os.Looper.loop(Looper.java:154) 
05-15 07:24:30.809: E/AndroidRuntime(25883):  at android.app.ActivityThread.main(ActivityThread.java:4624) 
05-15 07:24:30.809: E/AndroidRuntime(25883):  at java.lang.reflect.Method.invokeNative(Native Method) 
05-15 07:24:30.809: E/AndroidRuntime(25883):  at java.lang.reflect.Method.invoke(Method.java:511) 
05-15 07:24:30.809: E/AndroidRuntime(25883):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:809) 
05-15 07:24:30.809: E/AndroidRuntime(25883):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:576) 
05-15 07:24:30.809: E/AndroidRuntime(25883):  at dalvik.system.NativeStart.main(Native Method) 
05-15 07:24:30.809: E/AndroidRuntime(25883): Caused by: java.lang.NullPointerException 
05-15 07:24:30.809: E/AndroidRuntime(25883):  at com.example.mytaskmanager.Battery.setare(Battery.java:77) 
05-15 07:24:30.809: E/AndroidRuntime(25883):  at com.example.mytaskmanager.Battery$1.onReceive(Battery.java:120) 
05-15 07:24:30.809: E/AndroidRuntime(25883):  at android.app.LoadedApk$ReceiverDispatcher$Args.run(LoadedApk.java:746) 
05-15 07:24:30.809: E/AndroidRuntime(25883):  ... 9 more 

，代码：

public class Battery extends Fragment { 
    private TextView batteryInfo, memoryInfo, procent; 
    int health = 0, level=0, plugged=0, scale=0, status=0, temperature=0, voltage=0; 
    String technology = ""; 
    boolean present = false; 
    ProgressBar pb; 


    @Override 
    public View onCreateView(LayoutInflater inflater, ViewGroup container, 
      Bundle savedInstanceState) { 
     View myFragmentView = inflater.inflate(R.layout.layout, container, false); 
     return myFragmentView; 
    } 

    @Override 
    public void onResume() { 
     super.onResume(); 
     procent=(TextView)getActivity().findViewById(R.id.BatteryProc); 
     batteryInfo=(TextView)getActivity().findViewById(R.id.textViewBatteryInfo); 
     pb = (ProgressBar)getActivity().findViewById(R.id.progressbar); 
     memoryInfo = (TextView)getActivity().findViewById(R.id.memory); 
     setare(); 
     getMemInfo(); 

    } 



    public void setare(){ 

     procent.setText("Level: " + level + "%"); 
     pb.setProgress(level); 
     batteryInfo.setText(
       "Health: "+health+"\n"+ 
       "Plugged: "+plugged+"\n"+ 
       "Present: "+present+"\n"+ 
       "Scale: "+scale+"\n"+ 
       "Status: "+status+"\n"+ 
       "Technology: "+technology+"\n"+ 
       "Temperature: "+temperature+"\n"+ 
       "Voltage: "+voltage+"\n"); 

    } 

    @Override 
    public void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 

     getActivity().registerReceiver(this.batteryInfoReceiver, new IntentFilter(Intent.ACTION_BATTERY_CHANGED)); 
    } 

    private BroadcastReceiver batteryInfoReceiver = new BroadcastReceiver() { 
     @Override 
     public void onReceive(Context context, Intent intent) { 

      health= intent.getIntExtra(BatteryManager.EXTRA_HEALTH,0); 
      level= intent.getIntExtra(BatteryManager.EXTRA_LEVEL,0); 
      plugged= intent.getIntExtra(BatteryManager.EXTRA_PLUGGED,0); 
      present= intent.getExtras().getBoolean(BatteryManager.EXTRA_PRESENT); 
      scale= intent.getIntExtra(BatteryManager.EXTRA_SCALE,0); 
      status= intent.getIntExtra(BatteryManager.EXTRA_STATUS,0); 
      technology= intent.getExtras().getString(BatteryManager.EXTRA_TECHNOLOGY); 
      temperature= intent.getIntExtra(BatteryManager.EXTRA_TEMPERATURE,0); 
      voltage= intent.getIntExtra(BatteryManager.EXTRA_VOLTAGE,0); 

      batteryInfo=(TextView)getActivity().findViewById(R.id.textViewBatteryInfo); 
      pb = (ProgressBar)getActivity().findViewById(R.id.progressbar); 
      memoryInfo = (TextView)getActivity().findViewById(R.id.memory); 
      procent=(TextView)getActivity().findViewById(R.id.BatteryProc); 

      setare();   
      getMemInfo(); 

     } 
    }; 

Answer 1

视图层次结构中的procent batteryInfo视图在哪里？如果他们在您在onCreateView中膨胀的R.layout.layout中，将findViewByIds移动到onCreateView并使用myFragmentView代替getActivity（）： ex：procent = (TextView) myFragmentView.findViewById(R.id.BatteryProc);