NPE 列表片段视图

Question

在将我的活动转换为片段后，我仍然遇到问题。

在这里，我试图获取SQLite数据，并将其加载到listView中。在活动中，它工作得很好！

现在我在lv.setAdapter(adapter);得到一个NPE

    dbcon = new SQLController(getActivity());
    dbcon.open();
    addmem_bt = (Button) v.findViewById(R.id.add_bt_id);
    lv = (ListView) v.findViewById(R.id.memberList_id);
    // onClickListiner for addmember Button
    // Attach The Data From DataBase Into ListView Using Crusor Adapter
    Cursor cursor = dbcon.readData();
    String[] from = new String[]{DBhelper.MEMBER_ID, DBhelper.MEMBER_NAME};
    int[] to = new int[]{R.id.member_id, R.id.member_name};
    SimpleCursorAdapter adapter = new SimpleCursorAdapter(
            getActivity(), R.layout.view_member_entry, cursor, from, to);
    adapter.notifyDataSetChanged();
    lv.setAdapter(adapter);

我还有一个日志猫：

11-20 10:58:24.315    6539-6539/android.nl.hbbaa.bloodooa E/AndroidRuntime﹕ FATAL EXCEPTION: main
java.lang.NullPointerException
at android.hbbaa.startingpoint.nl.SQL.bababodFragment.onCreateView(bababodFragment.java:56)
at android.support.v4.app.Fragment.performCreateView(Fragment.java:1504)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:942)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1121)
at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:682)
at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1484)
at android.support.v4.app.FragmentManagerImpl$1.run(FragmentManager.java:450)
at android.os.Handler.handleCallback(Handler.java:730)
at android.os.Handler.dispatchMessage(Handler.java:92)
at android.os.Looper.loop(Looper.java:176)
at android.app.ActivityThread.main(ActivityThread.java:5419)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:525)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1046)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:862)
at dalvik.system.NativeStart.main(Native Method)

感谢

Answer 1

尝试使用 lv = (ListView) getActivity().findViewById(R.id.memberList_id); 而不是lv = (ListView) v.findViewById(R.id.memberList_id); 列表视图是活动 UI 的成员，而不是片段。