<?php
/**
* CDataProvider is a base class that implements the {@link IDataProvider} interface.
*
* Derived classes mainly need to implement three methods: {@link fetchData},
* {@link fetchKeys} and {@link calculateTotalItemCount}.
*
* @property string $id The unique ID that uniquely identifies the data provider among all data providers.
* @property CPagination $pagination The pagination object. If this is false, it means the pagination is disabled.
* @property CSort $sort The sorting object. If this is false, it means the sorting is disabled.
* @property array $data The list of data items currently available in this data provider.
* @property array $keys The list of key values corresponding to {@link data}. Each data item in {@link data}
* is uniquely identified by the corresponding key value in this array.
* @property integer $itemCount The number of data items in the current page.
* @property integer $totalItemCount Total number of possible data items.
*
* @author Qiang Xue <[email protected]>
* @package system.web
* @since 1.1
*/
abstract class CDataProvider extends CComponent implements IDataProvider
{
private $_id;
private $_data;
private $_keys;
private $_totalItemCount;
private $_sort;
private $_pagination;
/**
* Fetches the data from the persistent data storage.
* @return array list of data items
*/
abstract protected function fetchData();
/**
* Fetches the data item keys from the persistent data storage.
* @return array list of data item keys.
*/
abstract protected function fetchKeys();
/**
* Calculates the total number of data items.
* @return integer the total number of data items.
*/
abstract protected function calculateTotalItemCount();
/**
* Returns the ID that uniquely identifies the data provider.
* @return string the unique ID that uniquely identifies the data provider among all data providers.
*/
public function getId()
{
return $this->_id;
}
/**
* Sets the provider ID.
* @param string $value the unique ID that uniquely identifies the data provider among all data providers.
*/
public function setId($value)
{
$this->_id=$value;
}
/**
* Returns the pagination object.
* @param string $className the pagination object class name. Parameter is available since version 1.1.13.
* @return CPagination|false the pagination object. If this is false, it means the pagination is disabled.
*/
public function getPagination($className='CPagination')
{
if($this->_pagination===null)
{
$this->_pagination=new $className;
if(($id=$this->getId())!='')
$this->_pagination->pageVar=$id.'_page';
}
return $this->_pagination;
}
/**
* Sets the pagination for this data provider.
* @param mixed $value the pagination to be used by this data provider. This could be a {@link CPagination} object
* or an array used to configure the pagination object. If this is false, it means the pagination should be disabled.
*
* You can configure this property same way as a component:
* <pre>
* array(
* 'class' => 'MyPagination',
* 'pageSize' => 20,
* ),
* </pre>
*/
public function setPagination($value)
{
if(is_array($value))
{
if(isset($value['class']))
{
$pagination=$this->getPagination($value['class']);
unset($value['class']);
}
else
$pagination=$this->getPagination();
foreach($value as $k=>$v)
$pagination->$k=$v;
}
else
$this->_pagination=$value;
}
/**
* Returns the sort object.
* @param string $className the sorting object class name. Parameter is available since version 1.1.13.
* @return CSort|false the sorting object. If this is false, it means the sorting is disabled.
*/
public function getSort($className='CSort')
{
if($this->_sort===null)
{
$this->_sort=new $className;
if(($id=$this->getId())!='')
$this->_sort->sortVar=$id.'_sort';
}
return $this->_sort;
}
/**
* Sets the sorting for this data provider.
* @param mixed $value the sorting to be used by this data provider. This could be a {@link CSort} object
* or an array used to configure the sorting object. If this is false, it means the sorting should be disabled.
*
* You can configure this property same way as a component:
* <pre>
* array(
* 'class' => 'MySort',
* 'attributes' => array('name', 'weight'),
* ),
* </pre>
*/
public function setSort($value)
{
if(is_array($value))
{
if(isset($value['class']))
{
$sort=$this->getSort($value['class']);
unset($value['class']);
}
else
$sort=$this->getSort();
foreach($value as $k=>$v)
$sort->$k=$v;
}
else
$this->_sort=$value;
}
/**
* Returns the data items currently available.
* @param boolean $refresh whether the data should be re-fetched from persistent storage.
* @return array the list of data items currently available in this data provider.
*/
public function getData($refresh=false)
{
if($this->_data===null || $refresh)
$this->_data=$this->fetchData();
return $this->_data;
}
/**
* Sets the data items for this provider.
* @param array $value put the data items into this provider.
*/
public function setData($value)
{
$this->_data=$value;
}
/**
* Returns the key values associated with the data items.
* @param boolean $refresh whether the keys should be re-calculated.
* @return array the list of key values corresponding to {@link data}. Each data item in {@link data}
* is uniquely identified by the corresponding key value in this array.
*/
public function getKeys($refresh=false)
{
if($this->_keys===null || $refresh)
$this->_keys=$this->fetchKeys();
return $this->_keys;
}
/**
* Sets the data item keys for this provider.
* @param array $value put the data item keys into this provider.
*/
public function setKeys($value)
{
$this->_keys=$value;
}
/**
* Returns the number of data items in the current page.
* This is equivalent to <code>count($provider->getData())</code>.
* When {@link pagination} is set false, this returns the same value as {@link totalItemCount}.
* @param boolean $refresh whether the number of data items should be re-calculated.
* @return integer the number of data items in the current page.
*/
public function getItemCount($refresh=false)
{
return count($this->getData($refresh));
}
/**
* Returns the total number of data items.
* When {@link pagination} is set false, this returns the same value as {@link itemCount}.
* @param boolean $refresh whether the total number of data items should be re-calculated.
* @return integer total number of possible data items.
*/
public function getTotalItemCount($refresh=false)
{
if($this->_totalItemCount===null || $refresh)
$this->_totalItemCount=$this->calculateTotalItemCount();
return $this->_totalItemCount;
}
/**
* Sets the total number of data items.
* This method is provided in case when the total number cannot be determined by {@link calculateTotalItemCount}.
* @param integer $value the total number of data items.
* @since 1.1.1
*/
public function setTotalItemCount($value)
{
$this->_totalItemCount=$value;
}
}