无法在 Android Studio 中解析符号 getReadableDatabse

Question

我似乎无法完成这项工作。我在 android studio 中复制一个关于 SQLite 数据库的 youtube 视频教程，我遇到了这个错误。有人可以帮忙吗？谢谢！

public class DataListActivity extends ActionBarActivity {
    ListView listView;
    SQLiteDatabase sqLiteDatabase;
    UserDBHelper userDBHelper;
    Cursor cursor;
    ListDataAdapter listDataAdapter;


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

    listView = (ListView) findViewById(R.id.list_view);
    listDataAdapter = new ListDataAdapter(getApplication(), R.layout.row_layout);
    listView.setAdapter(listDataAdapter);
   userDBHelper = new UserDBHelper(getApplicationContext());
    sqLiteDatabase = new userDBHelper.getReadableDatabase();
    cursor = userDBHelper.getInformations(sqLiteDatabase);
    if (cursor.moveToFirst()) {
        do {

            String Fname, Lname, Email, Password, Contact, Address;
            Fname = cursor.getString(0);
            Lname = cursor.getString(1);
            Email = cursor.getString(2);
            Password = cursor.getString(3);
            Contact = cursor.getString(4);
            Address = cursor.getString(5);
            DataProvider dataProvider = new DataProvider(Fname, Lname, Email, Password, Contact, Address);
            listDataAdapter.add(dataProvider);


        } while (cursor.moveToNext());


    }


}

}

Answer 1

你放错了new:

sqLiteDatabase = new userDBHelper.getReadableDatabase();

删除它 - 您想在 userDBHelper 对象上调用 getReadableDatabase() 方法，而不是创建不存在的 userDBHelper.getReadableDatabase 类的新实例。