datagrid.php

<?php

namespace DataGrid;

class DataGrid
{
	/**
	 * Forge a new DataGrid
	 *
	 * @param  string|\Fuel\Core\Database_Query_Builder_Select  $table_or_query
	 * @param  string  $edit_link
	 *
	 * @return  static  a new DataGrid object
	 */
	public static function forge($table_or_query, $edit_link = null)
	{
		/* @var  DataGrid  $object */
		$object = new static($table_or_query);

		$edit_link and $object->set_edit_link($edit_link);

		return $object;
	}

	/**
	 * Add a Filter
	 *
	 * @throws  \InvalidArgumentException  when you try to add a filter with the same name as an existing filter
	 *
	 * @param  Filter  $filter
	 *
	 * @return  static  $this for chaining
	 */
	public function add_filter(Filter $filter)
	{
		$name = $filter->get_name();

		if (array_key_exists($name, $this->filters)) {
			throw new \InvalidArgumentException('Cannot add duplicate Filter to DataGrid: '.$name);
		}

		$this->filters[$name] = $filter;

		return $this;
	}
}

filter.php

<?php

namespace DataGrid;

class Filter
{

	/**
	 * Forge a new DataGrid Filter
	 *
	 * @param  string  $title
	 * @param  array|\Fuel\Core\Database_Query_Builder_Select  $query_or_array
	 * @param  array   $actions
	 * @param  string  $icon
	 *
	 * @return  static  a new DataGrid Filter object
	 */
	public static function forge($title, $query_or_array, $actions = [], $icon = null)
	{
		/* @var  Filter  $object */
		$object = new static($title, $query_or_array);

		$actions and $object->set_actions($actions);
		$icon and $object->set_icon($icon);

		return $object;
	}

}

gistfile1.txt

$datagrid = \DataGrid\DataGrid::forge($query)
	->add_filter(\DataGrid\Filter::forge(
		'Categories',
		[]
	));