<?php
/**
 * TDataGrid related class files.
 * This file contains the definition of the following classes:
 * TDataGrid, TDataGridItem, TDataGridItemCollection, TDataGridColumnCollection,
 * TDataGridPagerStyle, TDataGridItemEventParameter,
 * TDataGridCommandEventParameter, TDataGridSortCommandEventParameter,
 * TDataGridPageChangedEventParameter
 *
 * @author Qiang Xue <qiang.xue@gmail.com>
 * @link http://www.pradosoft.com/
 * @copyright Copyright &copy; 2005-2014 PradoSoft
 * @license http://www.pradosoft.com/license/
 * @package Prado\Web\UI\WebControls
 */

namespace Prado\Web\UI\WebControls;
use Prado\Exceptions\TInvalidDataTypeException;

/**
 * TDataGridItemCollection class.
 *
 * TDataGridItemCollection represents a collection of data grid items.
 *
 * @author Qiang Xue <qiang.xue@gmail.com>
 * @package Prado\Web\UI\WebControls
 * @since 3.0
 */
class TDataGridItemCollection extends \Prado\Collections\TList
{
	/**
	 * Inserts an item at the specified position.
	 * This overrides the parent implementation by inserting only TDataGridItem.
	 * @param integer the speicified position.
	 * @param mixed new item
	 * @throws TInvalidDataTypeException if the item to be inserted is not a TDataGridItem.
	 */
	public function insertAt($index,$item)
	{
		if($item instanceof TDataGridItem)
			parent::insertAt($index,$item);
		else
			throw new TInvalidDataTypeException('datagriditemcollection_datagriditem_required');
	}
}