我一直得到以下NullPointerException，我无法理解任何帮助将不胜感激。我正在使用片段
这是我在logcat中得到的：
11-24 13:48:11.130 24367-24367/com.example.hadi.do2get E/AndroidRuntime: FATAL EXCEPTION: main
11-24 13:48:11.130 24367-24367/com.example.hadi.do2get E/AndroidRuntime: Process: com.example.hadi.do2get, PID: 24367
11-24 13:48:11.130 24367-24367/com.example.hadi.do2get E/AndroidRuntime: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.ListView.setAdapter(android.widget.ListAdapter)' on a null object reference
11-24 13:48:11.130 24367-24367/com.example.hadi.do2get E/AndroidRuntime: at com.example.hadi.do2get.Rate_frag.onCreateView(Rate_frag.java:27)
11-24 13:48:11.130 24367-24367/com.example.hadi.do2get E/AndroidRuntime: at android.app.Fragment.performCreateView(Fragment.java:2053)
11-24 13:48:11.130 24367-24367/com.example.hadi.do2get E/AndroidRuntime: at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:894)
11-24 13:48:11.130 24367-24367/com.example.hadi.do2get E/AndroidRuntime: at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:1067)
11-24 13:48:11.130 24367-24367/com.example.hadi.do2get E/AndroidRuntime: at android.app.BackStackRecord.run(BackStackRecord.java:834)
11-24 13:48:11.130 24367-24367/com.example.hadi.do2get E/AndroidRuntime: at android.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1452)
11-24 13:48:11.130 24367-24367/com.example.hadi.do2get E/AndroidRuntime: at android.app.FragmentManagerImpl$1.run(FragmentManager.java:447)
11-24 13:48:11.130 24367-24367/com.example.hadi.do2get E/AndroidRuntime: at android.os.Handler.handleCallback(Handler.java:739)
11-24 13:48:11.130 24367-24367/com.example.hadi.do2get E/AndroidRuntime: at android.os.Handler.dispatchMessage(Handler.java:95)
11-24 13:48:11.130 24367-24367/com.example.hadi.do2get E/AndroidRuntime: at android.os.Looper.loop(Looper.java:135)
11-24 13:48:11.130 24367-24367/com.example.hadi.do2get E/AndroidRuntime: at android.app.ActivityThread.main(ActivityThread.java:5257)
11-24 13:48:11.130 24367-24367/com.example.hadi.do2get E/AndroidRuntime: at java.lang.reflect.Method.invoke(Native Method)
11-24 13:48:11.130 24367-24367/com.example.hadi.do2get E/AndroidRuntime: at java.lang.reflect.Method.invoke(Method.java:372)
11-24 13:48:11.130 24367-24367/com.example.hadi.do2get E/AndroidRuntime: at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903)
11-24 13:48:11.130 24367-24367/com.example.hadi.do2get E/AndroidRuntime: at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698)
RateAdapter：
public class RateAdapter extends ArrayAdapter<Annonce> {
TextView txtTitle;
ImageView imageView;
TextView extratxt;
RatingBar ratingBar;
private final Activity context;
LayoutInflater inflater;
public RateAdapter(Activity context, Annonce[] annoncer) {
super(context, R.layout.rate, annoncer);
this.context=context;
}
public View getView(int position,View view,ViewGroup parent) {
inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
view = inflater.inflate(R.layout.rate, null);
txtTitle = (TextView) view.findViewById(R.id.antitle);
imageView = (ImageView) view.findViewById(R.id.animage);
extratxt = (TextView) view.findViewById(R.id.andescrip);
ratingBar=(RatingBar) view.findViewById(R.id.ratingBar);
Annonce currentItem = getItem(position);
txtTitle.setText(currentItem.getItemname());
imageView.setImageResource(currentItem.getImgid());
extratxt.setText(currentItem.getDescription());
ratingBar.setNumStars(5);
return view;
}
}
这是Rate_Frag：
public class Rate_frag extends Fragment implements Liste {
ListView ratelist;
RatingBar ratebar;
RateAdapter rateAdapter;
public View onCreateView(LayoutInflater i, ViewGroup container, Bundle savedInstanceState) {
View rod = i.inflate(R.layout.rate, container, false);
ratelist = (ListView) rod.findViewById(R.id.ratelistview);
rateAdapter = new RateAdapter (getActivity(),ANNONCER);
ratelist.setAdapter(rateAdapter); //this is Rate_frag:27
return rod;
}
}
我的费率xml：
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="{relativePackage}.${activityClass}">
<ImageView
android:id="@+id/animage"
android:layout_width="100dp"
android:layout_height="100dp"
android:layout_marginLeft="15dp"
android:padding="10dp"
android:src="@drawable/sushi"
android:layout_below="@+id/antitle"
android:layout_alignParentStart="true" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/antitle"
android:layout_alignParentTop="true"
android:layout_alignStart="@+id/animage"
android:layout_marginTop="31dp"
android:textSize="20dp"
android:text="title"
android:layout_alignEnd="@+id/andescrip" />
<TextView
android:layout_width="168dp"
android:layout_height="wrap_content"
android:text="werqwjrlqewjrlqwrjwqeljrwljlqjkrlkewjqljkrlkqewjlkrjlqkewjkrqjlwrjq"
android:id="@+id/andescrip"
android:layout_alignTop="@+id/animage"
android:layout_toEndOf="@+id/animage" />
<RatingBar
android:layout_width="78dp"
android:layout_height="wrap_content"
android:id="@+id/ratingBar"
style="?android:attr/ratingBarStyleSmall"
android:numStars="5"
android:rating="5"
android:scaleX="0.5"
android:scaleY="0.5"
android:layout_alignTop="@+id/antitle"
android:layout_toEndOf="@+id/andescrip" />
这是我的费率列表XML：
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent" android:layout_height="match_parent">
<ListView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/ratelistview"
android:layout_alignParentTop="true"
android:layout_alignParentStart="true" />