simpleCursorAdapter 无法显示光标

Question

我想从数据库中检索数据。在我的 DBAdapter 中，我使用 fetchAllBooks 方法获取游标：

 public Cursor fetchAllBooks()
    {
        String selectQuery = "SELECT " + TABLE_TITLE + "." + KEY_TITLE_ID + " As _id, "
                + KEY_TITLE + ", " + KEY_PRICE + ", " + KEY_ISBN
                +", GROUP_CONCAT(" + KEY_AUTHOR + ", ', ') AS authors"
                + " FROM " + TABLE_TITLE + " JOIN " + TABLE_AUTHOR
                + " USING (" + KEY_TITLE_ID + ")"
                + " GROUP BY " + KEY_TITLE_ID;
        Cursor c = db.rawQuery(selectQuery, null);
        return c;
    }

在主要的 activity 中，我使用 fillData 方法来填充 ListView:

private void fillData() {

    Cursor c = db.fetchAllBooks();
    startManagingCursor(c);
    Log.d("count", c.getCount() + "");// could display the number of book. such as: count: 2; --- means cursor have 2 row(books)
    if(c.moveToFirst()) {
        do {
            Log.d("title", BookContract.getTitle(c)); // could display the title of each book;
        }while(c.moveToNext());
    }
    String[] from = new String[] {BookContract.KEY_TITLE, BookContract.KEY_AUTHORS};
    int[] to = new int[] { R.id.cart_row_title, R.id.cart_row_author};


    adapter = new SimpleCursorAdapter(this, R.layout.cart, c, from, to, 0);
    setListAdapter(adapter);
}

如你所见，LogCat可以显示光标的内容。这意味着我成功检索了光标。但是，listView 无法显示书名和作者。我的代码中没有使用任何 db.close() 或 cursor.close()。

cart_row.xml 表示列表中的每个行项目 view.And cart.xml 包含列表视图：

提前致谢。

Answer 1

我设法回答了我自己的问题。有点好笑...

请多多注意这句话：

the cart_row.xml which represent each row item in the list view. And the cart.xml which contain a list view:

simpleCursorAdapter 需要 cart_row.xml 而不是 cart.xml。所以将 simpleCursorAdapter 更改为：

adapter = new SimpleCursorAdapter(this, R.layout.cart_row, c, from, to, 0);

simpleCursorAdapter 无法显示光标

simpleCursorAdapter cannot display cursor

android

listview

simplecursoradapter