尝试使用sql数据提供程序在Yii 2中创建分页系统

Question

I'm trying to implement a pagination system with Yii 2 and making use of a SQL Data Provider but I am getting the below error:

Invalid argument supplied for foreach()

This is being caused by line 215 in the getOrders Yii method within the sort class; which is caused by this bit in the code below $models = $dataProvider->getModels();.

Here is the generalized code:

$sql = $this->db->createCommand("SELECT COUNT(*) FROM some_table WHERE some_id=:some_id");
$sql->bindValue(':some_id', $this->some_id);
$count = $sql->queryScalar();

$dataProvider = new SqlDataProvider([
    'sql' => 'SELECT * FROM some_table WHERE some_id=:some_id',
    'params' => [':some_id' => $this->some_id],
    'totalCount' => $count,
    'sort' => [
        'attributes' => [
            'sort_way_1' => [
                'asc' => ['col_1' => SORT_DESC, 'col_2' => SORT_ASC, 'col_3' => SORT_ASC],
                'desc' => ['col_1' => SORT_DESC, 'col_2' => SORT_DESC, 'col_3' => SORT_DESC],
                'default' => SORT_DESC,
                'label' => 'Sort Way 1',
            ],
            'sort_way_2' => [
                'asc' => ['col_1' => SORT_DESC, 'col_4' => SORT_ASC, 'col_3' => SORT_ASC],
                'desc' => ['col_1' => SORT_DESC, 'col_4' => SORT_DESC, 'col_3' => SORT_DESC],
                'default' => SORT_DESC,
                'label' => 'Sort Way 2',
            ],
            'sort_way_3' => [
                'asc' => ['col_1' => SORT_DESC, 'col_5' => SORT_ASC, 'col_3' => SORT_ASC],
                'desc' => ['col_1' => SORT_DESC, 'col_5' => SORT_DESC, 'col_3' => SORT_DESC],
                'default' => SORT_DESC,
                'label' => 'Sort Way 3',
            ],
            'sort_way_4' => [
                'asc' => ['col_1' => SORT_DESC, 'col_6' => SORT_ASC, 'col_3' => SORT_ASC],
                'desc' => ['col_1' => SORT_DESC, 'col_6' => SORT_DESC, 'col_3' => SORT_DESC],
                'default' => SORT_DESC,
                'label' => 'Sort Way 4',
            ],
        ],
        'enableMultiSort' => false,
        'defaultOrder' => [
                           'col_1' => SORT_DESC,
                           'col_2' => SORT_DESC,
                           'col_3' => SORT_DESC,
                           ],
    ],
    'pagination' => [
        'pageSize' => $this->per_page,
        'page' => $this->page,
        'pageSizeLimit' => [5,100],
        'pageSizeParam' => 'per_page',
        'totalCount' => $count,
    ],
]);

$models = $dataProvider->getModels();

Can anyone tell me what I am doing wrong here?

Answer 1

The problem is in defaultOrder declaration.

You should use only attributes declared in sort attributes section (in your case they are sort_way_1 to sort_way_4).

For order by sort_way_1 in descending direction just simply use:

'defaultOrder' => ['sort_way_1' => SORT_DESC],

And there is no need to copy all columns because your already described it explicitly here:

'sort_way_1' => [
    ...
    'desc' => [
        'col_1' => SORT_DESC,
        'col_2' => SORT_DESC,
        'col_3' => SORT_DESC,
    ],
    ...
],