Android SQLiteOpenHelper

Question

我的应用程序崩溃

java.lang.RuntimeException: Unable to start activity ComponentInfo{...}:
    java.lang.IllegalStateException: Couldn't read row 0, col 1 from CursorWindow. Make sure the Cursor is initialized correctly before accessing data from it.
    ...

下面是导致错误的方法：

public int getWeek(int yearAndWeek) throws CursorIndexOutOfBoundsException {
    SQLiteDatabase db = this.getReadableDatabase();

    String selectQuery = "SELECT  * FROM " + TABLE_WEEKS + " WHERE "
            + KEY_WEEK + " = " + yearAndWeek;

    Cursor c = db.rawQuery(selectQuery, null);

    if (c.getCount() > 0)
        c.moveToFirst();

    return c.getInt(c.getColumnIndex(KEY_WEEK_NUMBER));
}

此错误发生在这行return c.getInt(c.getColumnIndex(KEY_WEEK_NUMBER));中。请帮我解决这个问题。

Answer 1

要从方法中保持正确的答复，您可以尝试使用以下代码。

public int getWeek(int yearAndWeek) throws CursorIndexOutOfBoundsException {

    SQLiteDatabase db = this.getReadableDatabase();
    String selectQuery = "SELECT * FROM " + TABLE_WEEKS + " WHERE " + KEY_WEEK + " = " + yearAndWeek;
    Cursor c = db.rawQuery(selectQuery, null);

    if (c.getCount() > 0) {
        c.moveToFirst();
        return c.getInt(c.getColumnIndex(KEY_WEEK_NUMBER));
    }
    return -1;        
}