尝试访问关闭的 CursorWindow。最可能的原因：在调用此方法之前已停用光标

Question

如何解决给定的错误？当我尝试从操作栏刷新光标时会发生这种情况，有时当我在长按列表项后再次尝试删除时会发生这种情况。

主活动.java

public class MainActivity extends AppCompatActivity {
private final String QUERY_SELECTALL = "SELECT * FROM " + RjecnikDB.TABLE;
private RjecnikCursorAdapter adapter;
private RjecnikDB dbRjecnik;
private SQLiteDatabase db;
private Cursor cursor;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
}

@Override
protected void onRestart() {
    super.onRestart();
    refresh();
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    getMenuInflater().inflate(R.menu.menu_main, menu);
    return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    int id = item.getItemId();

    if (id == R.id.search_bar) {
        return true;
    } else if (id == R.id.refresh) {
        refresh();
    }

    return super.onOptionsItemSelected(item);
}
public void refresh() {
    dbRjecnik = RjecnikDB.getInstance(this);
    db = dbRjecnik.getReadableDatabase();
    cursor = db.rawQuery(QUERY_SELECTALL, null);
    adapter = RjecnikCursorAdapter.getInstance(this, cursor);
    adapter.changeCursor(cursor);
}

WordsListFragment.java

public class WordsListFragment extends Fragment {
private final String QUERY_SELECTALL = "SELECT * FROM " + RjecnikDB.TABLE;

private RjecnikCursorAdapter adapter;
private RjecnikDB dbRjecnik;
private SQLiteDatabase db;
private Cursor cursor;

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

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

    ListView listView = (ListView) view.findViewById(R.id.listView);
    fabAddWord = (FloatingActionButton) view.findViewById(R.id.fabAddWord);

    dbRjecnik = RjecnikDB.getInstance(getActivity());
    db = dbRjecnik.getWritableDatabase();
    cursor = db.rawQuery(QUERY_SELECTALL, null);
    adapter = RjecnikCursorAdapter.getInstance(getActivity(), cursor);
    listView.setAdapter(adapter);

    listView.setOnItemLongClickListener(new AdapterView.OnItemLongClickListener() {
        @Override
        public boolean onItemLongClick(AdapterView<?> parent, View view, int position, long id) {
            int _id = cursor.getInt(cursor.getColumnIndex(RjecnikDB.COLUMN_ID));

            DiscardDialogFragment newFragment = new DiscardDialogFragment(_id);
            newFragment.show(getFragmentManager(), "discard");
            return true;
        }
    });
    return view;
}

public void changeCursor() {
    dbRjecnik = RjecnikDB.getInstance(getActivity());
    db = dbRjecnik.getReadableDatabase();
    cursor = db.rawQuery(QUERY_SELECTALL, null);
    adapter.changeCursor(cursor);
}

public void deleteOnLongClick(int id) {
    db = dbRjecnik.getWritableDatabase();
    db.delete(RjecnikDB.TABLE, RjecnikDB.COLUMN_ID + " = ?", new String[] { Integer.toString(id) } );
}

public class DiscardDialogFragment extends DialogFragment {
    int colID;

    DiscardDialogFragment() {}
    DiscardDialogFragment(int colID) { this.colID = colID; }

    @Override
    public Dialog onCreateDialog(Bundle savedInstanceState) {
        AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
        builder.setMessage("Izbriši rije??")
                .setPositiveButton("IZBRIŠI",
                        new DialogInterface.OnClickListener() {
                            public void onClick(DialogInterface dialog, int id) {
                                deleteOnLongClick(colID);
                                changeCursor();
                                Toast.makeText(getActivity(),
                                        "Rije? je izbrisana iz baze", Toast.LENGTH_SHORT).show();
                            }
                        })
                .setNegativeButton("OTKAŽI", null);
        return builder.create();
    }
}

有没有人有一个想法在一个类中掌握这个changeCursor或refresh，我尝试了很多方法，但总是错误。

Answer 1

返回我的应用程序（从我的应用程序打开的另一个应用程序）时，我遇到了同样的错误。

我的解决方案是将我的spinnerAdapter.changeCursor(cursor)代码替换为spinnerAdapter.swapCursor(cursor).