从onCreateLoader返回的对象不能是非静态内部成员类：DumbLoader

Question

        // Home Activity class
        public class HomeActivity extends FragmentActivity implements LoaderCallbacks<Cursor> {
                DotCursorAdapter mAdapter;
                private ListView lv;
                private  final int LOADER_ID = 1932;

         DatabaseHandler dbHelper = new DatabaseHandler(this);

         @Override
         protected void onCreate(Bundle savedInstanceState) {
             super.onCreate(savedInstanceState);
                setContentView(R.layout.home_activity);
             lv = (ListView) findViewById(R.id.lists);


             mAdapter = new DotCursorAdapter(this, null,0);
             lv.setAdapter(mAdapter);

             getSupportLoaderManager().initLoader(LOADER_ID, null, this);   
        }





         @Override
         public Loader<Cursor> onCreateLoader(int i, Bundle bundle) {
             return new DumbLoader(this);
         }
         @Override
         public void onLoadFinished(Loader<Cursor> cursorLoader, Cursor cursor) {
             mAdapter.swapCursor(cursor);
         }
         @Override
         public void onLoaderReset(Loader<Cursor> cursorLoader) {
             mAdapter.swapCursor(null);
         }



        /**
         * DumbLoader sub class 
         */ 
         public class DumbLoader extends CursorLoader {
             private static final String TAG = "DumbLoader";
             public DumbLoader(Context context) {
                 super(context);
             }
             @Override
             public Cursor loadInBackground() {
                 Cursor c = dbHelper.fetchAllCountries();

                 return c;

             }
        }






        /**
         * DotCursor Adapter sub class
         */
        public final class DotCursorAdapter extends CursorAdapter {

             public DotCursorAdapter(Context context, Cursor cursor, int flags) {
                  super(context, cursor, 0);
              }



             @Override
             public void bindView(View view, Context context, Cursor cursor) {

                  // Find fields to populate in inflated template
                  TextView tvBody = (TextView) view.findViewById(R.id.header_text);

                  String body = cursor.getString(cursor.getColumnIndexOrThrow("fname"));
                  // Populate fields with extracted properties
                  tvBody.setText(body);


             }
             @Override
              public View newView(Context context, Cursor cursor, ViewGroup parent) {
                  return LayoutInflater.from(context).inflate(R.layout.list_cardview_activity, parent, false);
              }
            }
    }

public  Cursor fetchAllCountries() {
    SQLiteDatabase db = this.getReadableDatabase();

      Cursor mCursor = db.query(TABLE_LOGIN, new String[] {KEY_ID,KEY_FIRSTNAME},
        null, null, null, null, null);

      if (mCursor != null) {
       mCursor.moveToFirst();
      }
      return mCursor;
     }

下面也是我的日志猫详细信息

09-21 16:13:25.563:D/AbsListView（26541）：Get MotionRecognitionManager 09-21 16:13:25.568:D/AndroidRuntime(26541):关闭VM 09-21 16:13:25.573:W/DalvikVM(26541):ThreadId=1:线程退出未捕获异常（组=0x411372A0)09-21 16:13:25.573:E/AndroidRuntime(26541):致命异常：main 09-21 16:13:25.573:E/AndroidRuntime(26541):java.lang.RuntimeException：无法启动活动Iswell/com.Alliswell.Alliswell.HomeActivity}:java.lang.IllegalArgumentException：从onCreateLoader返回的对象不能是非静态内部成员类：DumbLoader{418dc668 id=0}09-21 16:13:25.573:e/AndroidRuntime(26541):at Android.app.ActivityThread.PerformLaunchActivite(ActivityThread.2110）09-21 16:13:25.573:e/AndroidRuntime(26541):at Android.app.ActivityThread.2110 E/AndroidRuntime（26541）：at android.app.activitythread.access$700(activitythread.java:140)09-21 16:13:25.573:E/AndroidRuntime(26541):at Android.app.ActivityThread$H.HandleMessage（ActivityThread.java:1237)09-21 16:13:25.573:E/AndroidRuntime(26541):at Android.os.handler.dispatchMessage(handler.java:99)09-21 16:13:25.573:E/AndroidRuntime(26541):at Android.os.looper.loop(looper.java:137)09-21 16:13:25.573:E/AndroidRuntime(26541):at-21 16:13:25.573:E/AndroidRuntime(26541):at java.lang.reflect.Method.invokenative（本机方法）09-21 16:13:25.573:E/AndroidRuntime(26541):at java.lang.reflect.Method.invoke.invokenative（本机方法）09-21 16:13:25.573:E/AndroidRuntime(26541):at java.lang.reflect.Method.invoke(Method.java:511）09-21 jygoteinit.main（zygoteinit.java：805）09-21 16:13:25.573:e/AndroidRuntime（26541）：at dalvik.system.nativeStart.main（原生方法）09-21 16:13:25.573:e/AndroidRuntime（26541）：by：java.lang.IllegalargUmentException：从onCreateLoader返回的对象不能是非静态内部成员类：DumbLoader{418dc668 id=0}09-21 16:13:25.573:e/AndroidRuntime(26541):at Android.support.v4.app.LoaderManagerImpl$LoaderInfo.start(LoaderManager.java:257)09-21 16:13:25.573:e/AndroidRuntime(26541):at Android.support.v4.app.LoaderManagerImpl.doStart(LoaderManager.java:714).v4.app.fragmentactivity.onstart（fragmentactivity.java：556）09-21 16:13:25.573:e/androidruntime（26541）：at android.app.instrumentation.callactivityonstart（instrumentation.java：1178）09-21 16:13:25.573:e/androidruntime（26541）：at android.app.activity.performstart（activity.java：5198）09-21 16:13:25.573:e/androidruntime（26541）：at.573:E/AndroidRuntime(26541):...11多

我想我在我的代码中做了一些错误的事情，如果有人能帮我解决这个问题，我将不胜感激。谢谢你。

Answer 1

您有两种方法来解决这个问题：

1.-创建dumbloader.java文件，并将其设置为：

public class DumbLoader extends CursorLoader {

     private DatabaseHandler mDBHelper;

     public DumbLoader(Context context, DatabaseHandler dbHelper) {
         super(context);
         mDBHelper = dbHelper;
     }

     @Override
     public Cursor loadInBackground() {
         return mDBHelper.fetchAllCountries();
     }
}

2.-对活动的DumbLoader嵌套类使用static修饰符，使其如下所示：

public class HomeActivity extends FragmentActivity implements LoaderCallbacks<Cursor> {

    //onCreate(), etc...

    //Make DumbLoader nested class STATIC
    public static class DumbLoader extends CursorLoader {

        private DatabaseHandler mDBHelper;

        public DumbLoader(Context context, DatabaseHandler dbHelper) {
            super(context);
            mDBHelper = dbHelper;
        }

        @Override
        public Cursor loadInBackground() {
            return mDBHelper.fetchAllCountries();
        }
}