3 files changed, 305 insertions, 465 deletions
diff --git a/framework/Web/UI/WebControls/TDataBoundControl.php b/framework/Web/UI/WebControls/TDataBoundControl.php
index 09023b66..798f9155 100644
--- a/framework/Web/UI/WebControls/TDataBoundControl.php
+++ b/framework/Web/UI/WebControls/TDataBoundControl.php
@@ -12,6 +12,7 @@
 
 Prado::using('System.Web.UI.WebControls.TDataSourceControl');
 Prado::using('System.Web.UI.WebControls.TDataSourceView');
+Prado::using('System.Collections.TPagedDataSource');
 
 /**
  * TDataBoundControl class.
@@ -20,7 +21,22 @@ Prado::using('System.Web.UI.WebControls.TDataSourceView');
  * data from data sources. It provides basic properties and methods that allow
  * the derived controls to associate with data sources and retrieve data from them.
  *
- * TBC...
+ * TBC....
+ *
+ * TDataBoundControl is equipped with paging capabilities. By setting
+ * {@link setAllowPaging AllowPaging} to true, the input data will be paged
+ * and only one page of data is actually populated into the data-bound control.
+ * This saves a lot of memory when dealing with larget datasets.
+ *
+ * To specify the number of data items displayed on each page, set
+ * the {@link setPageSize PageSize} property, and to specify which
+ * page of data to be displayed, set {@link setCurrentPageIndex CurrentPageIndex}.
+ *
+ * When the size of the original data is too big to be loaded all in the memory,
+ * one can enable custom paging. In custom paging, the total number of data items
+ * is specified manually via {@link setVirtualItemCount VirtualItemCount},
+ * and the data source only needs to contain the current page of data. To enable
+ * custom paging, set {@link setAllowCustomPaging AllowCustomPaging} to true.
  *
  * @author Qiang Xue <qiang.xue@gmail.com>
  * @version $Revision: $  $Date: $
@@ -152,6 +168,109 @@ abstract class TDataBoundControl extends TWebControl
 	}
 
 	/**
+	 * @return boolean whether paging is enabled. Defaults to false.
+	 */
+	public function getAllowPaging()
+	{
+		return $this->getViewState('AllowPaging',false);
+	}
+
+	/**
+	 * @param boolean whether paging is enabled
+	 */
+	public function setAllowPaging($value)
+	{
+		$this->setViewState('AllowPaging',TPropertyValue::ensureBoolean($value),false);
+	}
+
+	/**
+	 * @return boolean whether the custom paging is enabled. Defaults to false.
+	 */
+	public function getAllowCustomPaging()
+	{
+		return $this->getViewState('AllowCustomPaging',false);
+	}
+
+	/**
+	 * Sets a value indicating whether the custom paging should be enabled.
+	 * When the pager is in custom paging mode, the {@link setVirtualItemCount VirtualItemCount}
+	 * property is used to determine the paging, and the data items in the
+	 * {@link setDataSource DataSource} are considered to be in the current page.
+	 * @param boolean whether the custom paging is enabled
+	 */
+	public function setAllowCustomPaging($value)
+	{
+		$this->setViewState('AllowCustomPaging',TPropertyValue::ensureBoolean($value),false);
+	}
+
+	/**
+	 * @return integer the zero-based index of the current page. Defaults to 0.
+	 */
+	public function getCurrentPageIndex()
+	{
+		return $this->getViewState('CurrentPageIndex',0);
+	}
+
+	/**
+	 * @param integer the zero-based index of the current page
+	 * @throws TInvalidDataValueException if the value is less than 0
+	 */
+	public function setCurrentPageIndex($value)
+	{
+		if(($value=TPropertyValue::ensureInteger($value))<0)
+			throw new TInvalidDataValueException('databoundcontrol_currentpageindex_invalid',get_class($this));
+		$this->setViewState('CurrentPageIndex',$value,0);
+	}
+
+	/**
+	 * @return integer the number of data items on each page. Defaults to 10.
+	 */
+	public function getPageSize()
+	{
+		return $this->getViewState('PageSize',10);
+	}
+
+	/**
+	 * @param integer the number of data items on each page.
+	 * @throws TInvalidDataValueException if the value is less than 1
+	 */
+	public function setPageSize($value)
+	{
+		if(($value=TPropertyValue::ensureInteger($value))<1)
+			throw new TInvalidDataValueException('databoundcontrol_pagesize_invalid',get_class($this));
+		$this->setViewState('PageSize',TPropertyValue::ensureInteger($value),10);
+	}
+
+	/**
+	 * @return integer number of pages of data items available
+	 */
+	public function getPageCount()
+	{
+		return $this->getViewState('PageCount',1);
+	}
+
+	/**
+	 * @return integer virtual number of data items in the data source. Defaults to 0.
+	 * @see setAllowCustomPaging
+	 */
+	public function getVirtualItemCount()
+	{
+		return $this->getViewState('VirtualItemCount',0);
+	}
+
+	/**
+	 * @param integer virtual number of data items in the data source.
+	 * @throws TInvalidDataValueException if the value is less than 0
+	 * @see setAllowCustomPaging
+	 */
+	public function setVirtualItemCount($value)
+	{
+		if(($value=TPropertyValue::ensureInteger($value))<0)
+			throw new TInvalidDataValueException('databoundcontrol_virtualitemcount_invalid',get_class($this));
+		$this->setViewState('VirtualItemCount',$value,0);
+	}
+
+	/**
 	 * Sets a value indicating whether a databind call is required by the data bound control.
 	 * If true and the control has been prerendered while it uses the data source
 	 * specified by {@link setDataSourceID}, a databind call will be called by this method.
@@ -185,6 +304,20 @@ abstract class TDataBoundControl extends TWebControl
 	}
 
 	/**
+	 * @return TPagedDataSource creates a paged data source
+	 */
+	protected function createPagedDataSource()
+	{
+		$ds=new TPagedDataSource;
+		$ds->setCurrentPageIndex($this->getCurrentPageIndex());
+		$ds->setPageSize($this->getPageSize());
+		$ds->setAllowPaging($this->getAllowPaging());
+		$ds->setAllowCustomPaging($this->getAllowCustomPaging());
+		$ds->setVirtualItemCount($this->getVirtualItemCount());
+		return $ds;
+	}
+
+	/**
 	 * Performs databinding.
 	 * This method overrides the parent implementation by calling
 	 * {@link performSelect} which fetches data from data source and does
@@ -197,7 +330,22 @@ abstract class TDataBoundControl extends TWebControl
 		$this->onDataBinding(null);
 		$data=$this->getData();
 		if($data instanceof Traversable)
-			$this->performDataBinding($data);
+		{
+			if($this->getAllowPaging())
+			{
+				$ds=$this->createPagedDataSource();
+				$ds->setDataSource($data);
+				$this->setViewState('PageCount',$ds->getPageCount());
+				if($ds->getCurrentPageIndex()>=$ds->getPageCount())
+					throw new TInvalidDataValueException('databoundcontrol_currentpageindex_invalid',get_class($this));
+				$this->performDataBinding($ds);
+			}
+			else
+			{
+				$this->clearViewState('PageCount');
+				$this->performDataBinding($data);
+			}
+		}
 		$this->setIsDataBound(true);
 		$this->onDataBound(null);
 	}
@@ -336,7 +484,7 @@ abstract class TDataBoundControl extends TWebControl
 		else if(($value instanceof Traversable) || $value===null)
 			return $value;
 		else
-			throw new TInvalidDataTypeException('databoundcontrol_datasource_invalid');
+			throw new TInvalidDataTypeException('databoundcontrol_datasource_invalid',get_class($this));
 	}
 
 	public function getDataMember()
diff --git a/framework/Web/UI/WebControls/TDataGrid.php b/framework/Web/UI/WebControls/TDataGrid.php
index 4fe63f52..342a39ac 100644
--- a/framework/Web/UI/WebControls/TDataGrid.php
+++ b/framework/Web/UI/WebControls/TDataGrid.php
@@ -529,30 +529,6 @@ class TDataGrid extends TBaseDataList implements INamingContainer
 	}
 
 	/**
-	 * @return boolean whether the custom paging is enabled. Defaults to false.
-	 */
-	public function getAllowCustomPaging()
-	{
-		return $this->getViewState('AllowCustomPaging',false);
-	}
-
-	/**
-	 * @param boolean whether the custom paging is enabled
-	 */
-	public function setAllowCustomPaging($value)
-	{
-		$this->setViewState('AllowCustomPaging',TPropertyValue::ensureBoolean($value),false);
-	}
-
-	/**
-	 * @return boolean whether paging is enabled. Defaults to false.
-	 */
-	public function getAllowPaging()
-	{
-		return $this->getViewState('AllowPaging',false);
-	}
-
-	/**
 	 * @return boolean whether sorting is enabled. Defaults to false.
 	 */
 	public function getAllowSorting()
@@ -561,14 +537,6 @@ class TDataGrid extends TBaseDataList implements INamingContainer
 	}
 
 	/**
-	 * @param boolean whether paging is enabled
-	 */
-	public function setAllowPaging($value)
-	{
-		$this->setViewState('AllowPaging',TPropertyValue::ensureBoolean($value),false);
-	}
-
-	/**
 	 * @param boolean whether sorting is enabled
 	 */
 	public function setAllowSorting($value)
@@ -593,74 +561,6 @@ class TDataGrid extends TBaseDataList implements INamingContainer
 	}
 
 	/**
-	 * @return integer the zero-based index of the current page. Defaults to 0.
-	 */
-	public function getCurrentPageIndex()
-	{
-		return $this->getViewState('CurrentPageIndex',0);
-	}
-
-	/**
-	 * @param integer the zero-based index of the current page
-	 * @throws TInvalidDataValueException if the value is less than 0
-	 */
-	public function setCurrentPageIndex($value)
-	{
-		if(($value=TPropertyValue::ensureInteger($value))<0)
-			throw new TInvalidDataValueException('datagrid_currentpageindex_invalid');
-		$this->setViewState('CurrentPageIndex',$value,0);
-	}
-
-	/**
-	 * @return integer the number of rows displayed each page. Defaults to 10.
-	 */
-	public function getPageSize()
-	{
-		return $this->getViewState('PageSize',10);
-	}
-
-	/**
-	 * @param integer the number of rows displayed within a page
-	 * @throws TInvalidDataValueException if the value is less than 1
-	 */
-	public function setPageSize($value)
-	{
-		if(($value=TPropertyValue::ensureInteger($value))<1)
-			throw new TInvalidDataValueException('datagrid_pagesize_invalid');
-		$this->setViewState('PageSize',TPropertyValue::ensureInteger($value),10);
-	}
-
-	/**
-	 * @return integer number of pages of items available
-	 */
-	public function getPageCount()
-	{
-		if($this->_pagedDataSource)
-			return $this->_pagedDataSource->getPageCount();
-		else
-			return $this->getViewState('PageCount',0);
-	}
-
-	/**
-	 * @return integer virtual number of items in the grid. Defaults to 0, meaning not set.
-	 */
-	public function getVirtualItemCount()
-	{
-		return $this->getViewState('VirtualItemCount',0);
-	}
-
-	/**
-	 * @param integer virtual number of items in the grid
-	 * @throws TInvalidDataValueException if the value is less than 0
-	 */
-	public function setVirtualItemCount($value)
-	{
-		if(($value=TPropertyValue::ensureInteger($value))<0)
-			throw new TInvalidDataValueException('datagrid_virtualitemcount_invalid');
-		$this->setViewState('VirtualItemCount',$value,0);
-	}
-
-	/**
 	 * @return boolean whether the header should be displayed. Defaults to true.
 	 */
 	public function getShowHeader()
@@ -955,21 +855,6 @@ class TDataGrid extends TBaseDataList implements INamingContainer
 			}
 			$this->restoreGridFromViewState();
 		}
-		$this->clearViewState('ItemCount');
-	}
-
-	/**
-	 * @return TPagedDataSource creates a paged data source
-	 */
-	private function createPagedDataSource()
-	{
-		$ds=new TPagedDataSource;
-		$ds->setCurrentPageIndex($this->getCurrentPageIndex());
-		$ds->setPageSize($this->getPageSize());
-		$ds->setAllowPaging($this->getAllowPaging());
-		$ds->setAllowCustomPaging($this->getAllowCustomPaging());
-		$ds->setVirtualItemCount($this->getVirtualItemCount());
-		return $ds;
 	}
 
 	/**
@@ -992,42 +877,27 @@ class TDataGrid extends TBaseDataList implements INamingContainer
 	protected function restoreGridFromViewState()
 	{
 		$this->reset();
-		$itemCount=$this->getViewState('ItemCount',0);
-		$this->_pagedDataSource=$ds=$this->createPagedDataSource();
-		$allowPaging=$ds->getAllowPaging();
-		if($allowPaging && $ds->getAllowCustomPaging())
-			$ds->setDataSource(new TDummyDataSource($itemCount));
-		else
-			$ds->setDataSource(new TDummyDataSource($this->getViewState('DataSourceCount',0)));
 
-		if($ds->getCount()===0 && $ds->getCurrentPageIndex()===0 && $this->_emptyTemplate!==null)
-		{
-			$this->_emptyTemplate->instantiateIn($this);
-			$this->_useEmptyTemplate=true;
-			$this->clearViewState('ItemCount');
-			$this->clearViewState('PageCount');
-			$this->clearViewState('DataSourceCount');
-			return;
-		}
+		$allowPaging=$this->getAllowPaging();
+
+		$itemCount=$this->getViewState('ItemCount',0);
+		$dsIndex=$this->getViewState('DataSourceIndex',0);
 
 		$columns=new TList($this->getColumns());
 		$columns->mergeWith($this->_autoColumns);
 
 		$items=$this->getItems();
-		$items->clear();
 
 		if($columns->getCount())
 		{
 			foreach($columns as $column)
 				$column->initialize();
 			if($allowPaging)
-				$this->_topPager=$this->createPager($ds);
+				$this->_topPager=$this->createPager();
 			$this->_header=$this->createItemInternal(-1,-1,self::IT_HEADER,false,null,$columns);
 			$selectedIndex=$this->getSelectedItemIndex();
 			$editIndex=$this->getEditItemIndex();
-			$index=0;
-			$dsIndex=$ds->getAllowPaging()?$ds->getFirstIndexInPage():0;
-			foreach($ds as $data)
+			for($index=0;$index<$itemCount;++$index)
 			{
 				if($index===$editIndex)
 					$itemType=self::IT_EDITITEM;
@@ -1038,14 +908,17 @@ class TDataGrid extends TBaseDataList implements INamingContainer
 				else
 					$itemType=self::IT_ITEM;
 				$items->add($this->createItemInternal($index,$dsIndex,$itemType,false,null,$columns));
-				$index++;
 				$dsIndex++;
 			}
 			$this->_footer=$this->createItemInternal(-1,-1,self::IT_FOOTER,false,null,$columns);
 			if($allowPaging)
-				$this->_bottomPager=$this->createPager($ds);
+				$this->_bottomPager=$this->createPager();
+		}
+		if(!$dsIndex && $this->_emptyTemplate!==null)
+		{
+			$this->_useEmptyTemplate=true;
+			$this->_emptyTemplate->instantiateIn($this);
 		}
-		$this->_pagedDataSource=null;
 	}
 
 	/**
@@ -1060,29 +933,12 @@ class TDataGrid extends TBaseDataList implements INamingContainer
 		$keys=$this->getDataKeys();
 		$keys->clear();
 		$keyField=$this->getDataKeyField();
-		$this->_pagedDataSource=$ds=$this->createPagedDataSource();
-		$ds->setDataSource($data);
-
-		$allowPaging=$ds->getAllowPaging();
-		if($allowPaging && $ds->getCurrentPageIndex()>=$ds->getPageCount())
-			throw new TInvalidDataValueException('datagrid_currentpageindex_invalid');
-
-		if($ds->getCount()===0 && $ds->getCurrentPageIndex()===0 && $this->_emptyTemplate!==null)
-		{
-			$this->_useEmptyTemplate=true;
-			$this->_emptyTemplate->instantiateIn($this);
-			$this->dataBindChildren();
-			$this->clearViewState('ItemCount');
-			$this->clearViewState('PageCount');
-			$this->clearViewState('DataSourceCount');
-			return;
-		}
 
 		// get all columns
 		if($this->getAutoGenerateColumns())
 		{
 			$columns=new TList($this->getColumns());
-			$autoColumns=$this->createAutoColumns($ds);
+			$autoColumns=$this->createAutoColumns($data);
 			$columns->mergeWith($autoColumns);
 		}
 		else
@@ -1090,22 +946,23 @@ class TDataGrid extends TBaseDataList implements INamingContainer
 
 		$items=$this->getItems();
 
+		$index=0;
+		$allowPaging=$this->getAllowPaging() && ($data instanceof TPagedDataSource);
+		$dsIndex=$allowPaging?$data->getFirstIndexInPage():0;
+		$this->setViewState('DataSourceIndex',$dsIndex,0);
 		if($columns->getCount())
 		{
 			foreach($columns as $column)
 				$column->initialize();
-			$allowPaging=$ds->getAllowPaging();
 			if($allowPaging)
-				$this->_topPager=$this->createPager($ds);
+				$this->_topPager=$this->createPager();
 			$this->_header=$this->createItemInternal(-1,-1,self::IT_HEADER,true,null,$columns);
 			$selectedIndex=$this->getSelectedItemIndex();
 			$editIndex=$this->getEditItemIndex();
-			$index=0;
-			$dsIndex=$allowPaging?$ds->getFirstIndexInPage():0;
-			foreach($ds as $key=>$data)
+			foreach($data as $key=>$row)
 			{
 				if($keyField!=='')
-					$keys->add($this->getDataFieldValue($data,$keyField));
+					$keys->add($this->getDataFieldValue($row,$keyField));
 				else
 					$keys->add($key);
 				if($index===$editIndex)
@@ -1116,24 +973,21 @@ class TDataGrid extends TBaseDataList implements INamingContainer
 					$itemType=self::IT_ALTERNATINGITEM;
 				else
 					$itemType=self::IT_ITEM;
-				$items->add($this->createItemInternal($index,$dsIndex,$itemType,true,$data,$columns));
+				$items->add($this->createItemInternal($index,$dsIndex,$itemType,true,$row,$columns));
 				$index++;
 				$dsIndex++;
 			}
 			$this->_footer=$this->createItemInternal(-1,-1,self::IT_FOOTER,true,null,$columns);
 			if($allowPaging)
-				$this->_bottomPager=$this->createPager($ds);
-			$this->setViewState('ItemCount',$index,0);
-			$this->setViewState('PageCount',$ds->getPageCount(),0);
-			$this->setViewState('DataSourceCount',$ds->getDataSourceCount(),0);
+				$this->_bottomPager=$this->createPager();
 		}
-		else
+		$this->setViewState('ItemCount',$index,0);
+		if(!$dsIndex && $this->_emptyTemplate!==null)
 		{
-			$this->clearViewState('ItemCount');
-			$this->clearViewState('PageCount');
-			$this->clearViewState('DataSourceCount');
+			$this->_useEmptyTemplate=true;
+			$this->_emptyTemplate->instantiateIn($this);
+			$this->dataBindChildren();
 		}
-		$this->_pagedDataSource=null;
 	}
 
 	/**
@@ -1191,10 +1045,10 @@ class TDataGrid extends TBaseDataList implements INamingContainer
 		}
 	}
 
-	private function createPager($pagedDataSource)
+	private function createPager()
 	{
 		$pager=new TDataGridPager($this);
-		$this->buildPager($pager,$pagedDataSource);
+		$this->buildPager($pager);
 		$this->onPagerCreated(new TDataGridPagerEventParameter($pager));
 		$this->getControls()->add($pager);
 		return $pager;
@@ -1203,81 +1057,87 @@ class TDataGrid extends TBaseDataList implements INamingContainer
 	/**
 	 * Builds the pager content based on pager style.
 	 * @param TDataGridPager the container for the pager
-	 * @param TPagedDataSource data source bound to the datagrid
 	 */
-	protected function buildPager($pager,$dataSource)
+	protected function buildPager($pager)
 	{
 		switch($this->getPagerStyle()->getMode())
 		{
 			case 'NextPrev':
-				$this->buildNextPrevPager($pager,$dataSource);
+				$this->buildNextPrevPager($pager);
 				break;
 			case 'Numeric':
-				$this->buildNumericPager($pager,$dataSource);
+				$this->buildNumericPager($pager);
 				break;
 		}
 	}
 
 	/**
 	 * Creates a pager button.
-	 * @param string button type, LinkButton or PushButton
+	 * Depending on the button type, a TLinkButton or a TButton may be created.
+	 * If it is enabled (clickable), its command name and parameter will also be set.
+	 * Derived classes may override this method to create additional types of buttons, such as TImageButton.
+	 * @param string button type, either LinkButton or PushButton
 	 * @param boolean whether the button should be enabled
+	 * @param string caption of the button
+	 * @param string CommandName corresponding to the OnCommand event of the button
+	 * @param string CommandParameter corresponding to the OnCommand event of the button
 	 * @return mixed the button instance
 	 */
-	protected function createPagerButton($buttonType,$enabled)
+	protected function createPagerButton($buttonType,$enabled,$text,$commandName,$commandParameter)
 	{
 		if($buttonType==='LinkButton')
 		{
-			return $enabled?new TLinkButton:new TLabel;
+			if($enabled)
+				$button=new TLinkButton;
+			else
+			{
+				$button=new TLabel;
+				$button->setText($text);
+				return $button;
+			}
 		}
 		else
 		{
 			$button=new TButton;
 			if(!$enabled)
 				$button->setEnabled(false);
-			return $button;
 		}
+		$button->setText($text);
+		$button->setCommandName($commandName);
+		$button->setCommandParameter($commandParameter);
+		$button->setCausesValidation(false);
+		return $button;
 	}
 
 	/**
 	 * Builds a next-prev pager
 	 * @param TDataGridPager the container for the pager
-	 * @param TPagedDataSource data source bound to the datagrid
 	 */
-	protected function buildNextPrevPager($pager,$dataSource)
+	protected function buildNextPrevPager($pager)
 	{
 		$style=$this->getPagerStyle();
 		$buttonType=$style->getButtonType();
 		$controls=$pager->getControls();
-		if($dataSource->getIsFirstPage())
+		$currentPageIndex=$this->getCurrentPageIndex();
+		if($currentPageIndex===0)
 		{
-			$label=$this->createPagerButton($buttonType,false);
-			$label->setText($style->getPrevPageText());
+			$label=$this->createPagerButton($buttonType,false,$style->getPrevPageText(),'','');
 			$controls->add($label);
 		}
 		else
 		{
-			$button=$this->createPagerButton($buttonType,true);
-			$button->setText($style->getPrevPageText());
-			$button->setCommandName(self::CMD_PAGE);
-			$button->setCommandParameter(self::CMD_PAGE_PREV);
-			$button->setCausesValidation(false);
+			$button=$this->createPagerButton($buttonType,true,$style->getPrevPageText(),self::CMD_PAGE,self::CMD_PAGE_PREV);
 			$controls->add($button);
 		}
-		$controls->add('&nbsp;');
-		if($dataSource->getIsLastPage())
+		$controls->add("\n");
+		if($currentPageIndex===$this->getPageCount()-1)
 		{
-			$label=$this->createPagerButton($buttonType,false);
-			$label->setText($style->getNextPageText());
+			$label=$this->createPagerButton($buttonType,false,$style->getNextPageText(),'','');
 			$controls->add($label);
 		}
 		else
 		{
-			$button=$this->createPagerButton($buttonType,true);
-			$button->setText($style->getNextPageText());
-			$button->setCommandName(self::CMD_PAGE);
-			$button->setCommandParameter(self::CMD_PAGE_NEXT);
-			$button->setCausesValidation(false);
+			$button=$this->createPagerButton($buttonType,true,$style->getNextPageText(),self::CMD_PAGE,self::CMD_PAGE_NEXT);
 			$controls->add($button);
 		}
 	}
@@ -1285,15 +1145,14 @@ class TDataGrid extends TBaseDataList implements INamingContainer
 	/**
 	 * Builds a numeric pager
 	 * @param TDataGridPager the container for the pager
-	 * @param TPagedDataSource data source bound to the datagrid
 	 */
-	protected function buildNumericPager($pager,$dataSource)
+	protected function buildNumericPager($pager)
 	{
 		$style=$this->getPagerStyle();
 		$buttonType=$style->getButtonType();
 		$controls=$pager->getControls();
-		$pageCount=$dataSource->getPageCount();
-		$pageIndex=$dataSource->getCurrentPageIndex()+1;
+		$pageCount=$this->getPageCount();
+		$pageIndex=$this->getCurrentPageIndex()+1;
 		$maxButtonCount=$style->getPageButtonCount();
 		$buttonCount=$maxButtonCount>$pageCount?$pageCount:$maxButtonCount;
 		$startPageIndex=1;
@@ -1312,51 +1171,40 @@ class TDataGrid extends TBaseDataList implements INamingContainer
 
 		if($startPageIndex>1)
 		{
-			$button=$this->createPagerButton($buttonType,true);
-			$button->setText($style->getPrevPageText());
-			$button->setCommandName(self::CMD_PAGE);
-			$button->setCommandParameter($startPageIndex-1);
-			$button->setCausesValidation(false);
+			$prevPageIndex=$startPageIndex-1;
+			$button=$this->createPagerButton($buttonType,true,$style->getPrevPageText(),self::CMD_PAGE,"$prevPageIndex");
 			$controls->add($button);
-			$controls->add('&nbsp;');
+			$controls->add("\n");
 		}
 
 		for($i=$startPageIndex;$i<=$endPageIndex;++$i)
 		{
 			if($i===$pageIndex)
 			{
-				$label=$this->createPagerButton($buttonType,false);
-				$label->setText("$i");
+				$label=$this->createPagerButton($buttonType,false,"$i",'','');
 				$controls->add($label);
 			}
 			else
 			{
-				$button=$this->createPagerButton($buttonType,true);
-				$button->setText("$i");
-				$button->setCommandName(self::CMD_PAGE);
-				$button->setCommandParameter($i);
-				$button->setCausesValidation(false);
+				$button=$this->createPagerButton($buttonType,true,"$i",self::CMD_PAGE,"$i");
 				$controls->add($button);
 			}
 			if($i<$endPageIndex)
-				$controls->add('&nbsp;');
+				$controls->add("\n");
 		}
 
 		if($pageCount>$endPageIndex)
 		{
-			$controls->add('&nbsp;');
-			$button=$this->createPagerButton($buttonType,true);
-			$button->setText($style->getNextPageText());
-			$button->setCommandName(self::CMD_PAGE);
-			$button->setCommandParameter($endPageIndex+1);
-			$button->setCausesValidation(false);
+			$controls->add("\n");
+			$nextPageIndex=$endPageIndex+1;
+			$button=$this->createPagerButton($buttonType,true,$style->getNextPageText(),self::CMD_PAGE,"$nextPageIndex");
 			$controls->add($button);
 		}
 	}
 
 	/**
 	 * Automatically generates datagrid columns based on datasource schema
-	 * @param TPagedDataSource data source bound to the datagrid
+	 * @param Traversable data source bound to the datagrid
 	 * @return TDataGridColumnCollection
 	 */
 	protected function createAutoColumns($dataSource)
diff --git a/framework/Web/UI/WebControls/TPager.php b/framework/Web/UI/WebControls/TPager.php
index f802e8d7..0401c4f2 100644
--- a/framework/Web/UI/WebControls/TPager.php
+++ b/framework/Web/UI/WebControls/TPager.php
@@ -10,27 +10,18 @@
  * @package System.Web.UI.WebControls
  */
 
-Prado::using('System.Web.UI.WebControls.TDataBoundControl');
-Prado::using('System.Web.UI.WebControls.TPanelStyle');
-Prado::using('System.Collections.TPagedDataSource');
-Prado::using('System.Collections.TDummyDataSource');
-
 /**
  * TPager class.
  *
- * TPager creates a pager that controls the paging of the data populated
- * to a data-bound control specified by {@link setControlToPaginate ControlToPaginate}.
- * To specify the number of data items displayed on each page, set
- * the {@link setPageSize PageSize} property, and to specify which
- * page of data to be displayed, set {@link setCurrentPageIndex CurrentPageIndex}.
- *
- * When the size of the original data is too big to be loaded all in the memory,
- * one can enable custom paging. In custom paging, the total number of data items
- * is specified manually via {@link setVirtualItemCount VirtualItemCount}, and the data source
- * only needs to contain the current page of data. To enable custom paging,
- * set {@link setAllowCustomPaging AllowCustomPaging} to true.
+ * TPager creates a pager that provides UI for end-users to interactively
+ * specify which page of data to be rendered in a {@link TDataBoundControl}-derived control,
+ * such as {@link TDataList}, {@link TRepeater}, {@link TCheckBoxList}, etc.
+ * The target data-bound control is specified by {@link setControlToPaginate ControlToPaginate},
+ * which must be the ID path of the target control reaching from the pager's
+ * naming container. Note, the target control must have its {@link TDataBoundControl::setAllowPaging AllowPaging}
+ * set to true.
  *
- * TPager can be in one of three {@link setMode Mode}:
+ * TPager can display three different UIs, specified via {@link setMode Mode}:
  * - NextPrev: a next page and a previous page button are rendered.
  * - Numeric: a list of page index buttons are rendered.
  * - List: a dropdown list of page indices are rendered.
@@ -39,27 +30,17 @@ Prado::using('System.Collections.TDummyDataSource');
  * the end-user interacts with it and specifies a new page (e.g. clicking
  * on a page button that leads to a new page.) The new page index may be obtained
  * from the event parameter's property {@link TPagerPageChangedEventParameter::getNewPageIndex NewPageIndex}.
+ * Normally, in the event handler, one can set the {@link TDataBoundControl::getCurrentPageIndex CurrentPageIndex}
+ * to this new page index so that the new page of data is rendered.
  *
- * When multiple pagers are associated with the same data-bound control,
- * these pagers will do synchronization among each other so that the interaction
- * with one pager will automatically update the UI of the other relevant pagers.
- *
- * The following example shows a typical usage of TPager:
- * <code>
- * $pager->ControlToPaginate="Path.To.Control";
- * $pager->DataSource=$data;
- * $pager->dataBind();
- * </code>
- * Note, the data is assigned to the pager and dataBind() is invoked against the pager.
- * Without the pager, one has to set datasource for the target control and call
- * its dataBind() directly.
+ * Multiple pagers can be associated with the same data-bound control.
  *
  * @author Qiang Xue <qiang.xue@gmail.com>
  * @version $Revision: $  $Date: $
  * @package System.Web.UI.WebControls
  * @since 3.0.2
  */
-class TPager extends TDataBoundControl implements INamingContainer
+class TPager extends TWebControl implements INamingContainer
 {
 	/**
 	 * Command name that TPager understands.
@@ -71,36 +52,6 @@ class TPager extends TDataBoundControl implements INamingContainer
 	const CMD_PAGE_LAST='Last';
 
 	/**
-	 * @var array list of all pagers, used to synchronize their appearance
-	 */
-	static private $_pagers=array();
-
-	/**
-	 * Registers the pager itself to a global list.
-	 * This method overrides the parent implementation and is invoked during
-	 * OnInit control lifecycle.
-	 * @param mixed event parameter
-	 */
-	public function onInit($param)
-	{
-		parent::onInit($param);
-		self::$_pagers[]=$this;
-	}
-
-	/**
-	 * Unregisters the pager from a global list.
-	 * This method overrides the parent implementation and is invoked during
-	 * OnUnload control lifecycle.
-	 * @param mixed event parameter
-	 */
-	public function onUnload($param)
-	{
-		parent::onUnload($param);
-		if(($index=array_search($this,self::$_pagers,true))!==false)
-			unset(self::$_pagers[$index]);
-	}
-
-	/**
 	 * Restores the pager state.
 	 * This method overrides the parent implementation and is invoked when
 	 * the control is loading persistent state.
@@ -108,10 +59,11 @@ class TPager extends TDataBoundControl implements INamingContainer
 	public function loadState()
 	{
 		parent::loadState();
-		if(!$this->getEnableViewState(true))
-			return;
-		if(!$this->getIsDataBound())
-			$this->restoreFromViewState();
+		if($this->getEnableViewState(true))
+		{
+			$this->getControls()->clear();
+			$this->buildPager();
+		}
 	}
 
 	/**
@@ -134,107 +86,6 @@ class TPager extends TDataBoundControl implements INamingContainer
 	}
 
 	/**
-	 * @return integer the zero-based index of the current page. Defaults to 0.
-	 */
-	public function getCurrentPageIndex()
-	{
-		return $this->getViewState('CurrentPageIndex',0);
-	}
-
-	/**
-	 * @param integer the zero-based index of the current page
-	 * @throws TInvalidDataValueException if the value is less than 0
-	 */
-	public function setCurrentPageIndex($value)
-	{
-		if(($value=TPropertyValue::ensureInteger($value))<0)
-			throw new TInvalidDataValueException('pager_currentpageindex_invalid');
-		$this->setViewState('CurrentPageIndex',$value,0);
-	}
-
-	/**
-	 * @return integer the number of data items on each page. Defaults to 10.
-	 */
-	public function getPageSize()
-	{
-		return $this->getViewState('PageSize',10);
-	}
-
-	/**
-	 * @param integer the number of data items on each page.
-	 * @throws TInvalidDataValueException if the value is less than 1
-	 */
-	public function setPageSize($value)
-	{
-		if(($value=TPropertyValue::ensureInteger($value))<1)
-			throw new TInvalidDataValueException('pager_pagesize_invalid');
-		$this->setViewState('PageSize',TPropertyValue::ensureInteger($value),10);
-	}
-
-	/**
-	 * @return integer number of pages
-	 */
-	public function getPageCount()
-	{
-		if(($count=$this->getItemCount())<1)
-			return 1;
-		else
-		{
-			$pageSize=$this->getPageSize();
-			return (int)(($count+$pageSize-1)/$pageSize);
-		}
-	}
-
-	/**
-	 * @return boolean whether the custom paging is enabled. Defaults to false.
-	 */
-	public function getAllowCustomPaging()
-	{
-		return $this->getViewState('AllowCustomPaging',false);
-	}
-
-	/**
-	 * Sets a value indicating whether the custom paging should be enabled.
-	 * When the pager is in custom paging mode, the {@link setVirtualItemCount VirtualItemCount}
-	 * property is used to determine the paging, and the data items in the
-	 * {@link setDataSource DataSource} are considered to be in the current page.
-	 * @param boolean whether the custom paging is enabled
-	 */
-	public function setAllowCustomPaging($value)
-	{
-		$this->setViewState('AllowCustomPaging',TPropertyValue::ensureBoolean($value),false);
-	}
-
-	/**
-	 * @return integer virtual number of data items in the data source. Defaults to 0.
-	 * @see setAllowCustomPaging
-	 */
-	public function getVirtualItemCount()
-	{
-		return $this->getViewState('VirtualItemCount',0);
-	}
-
-	/**
-	 * @param integer virtual number of data items in the data source.
-	 * @throws TInvalidDataValueException if the value is less than 0
-	 * @see setAllowCustomPaging
-	 */
-	public function setVirtualItemCount($value)
-	{
-		if(($value=TPropertyValue::ensureInteger($value))<0)
-			throw new TInvalidDataValueException('pager_virtualitemcount_invalid');
-		$this->setViewState('VirtualItemCount',$value,0);
-	}
-
-	/**
-	 * @return integer total number of items in the datasource.
-	 */
-	public function getItemCount()
-	{
-		return $this->getViewState('ItemCount',0);
-	}
-
-	/**
 	 * @return string pager mode. Defaults to 'NextPrev'.
 	 */
 	public function getMode()
@@ -350,38 +201,57 @@ class TPager extends TDataBoundControl implements INamingContainer
 	}
 
 	/**
-	 * @return TPagedDataSource creates a paged data source
+	 * @return integer the zero-based index of the current page. Defaults to 0.
 	 */
-	private function createPagedDataSource()
+	public function getCurrentPageIndex()
 	{
-		$ds=new TPagedDataSource;
-		$ds->setAllowPaging(true);
-		$customPaging=$this->getAllowCustomPaging();
-		$ds->setAllowCustomPaging($customPaging);
-		$ds->setCurrentPageIndex($this->getCurrentPageIndex());
-		$ds->setPageSize($this->getPageSize());
-		if($customPaging)
-			$ds->setVirtualItemCount($this->getVirtualItemCount());
-		return $ds;
+		return $this->getViewState('CurrentPageIndex',0);
 	}
 
 	/**
-	 * Removes the existing child controls.
+	 * @param integer the zero-based index of the current page
+	 * @throws TInvalidDataValueException if the value is less than 0
 	 */
-	protected function reset()
+	protected function setCurrentPageIndex($value)
 	{
-		$this->getControls()->clear();
+		if(($value=TPropertyValue::ensureInteger($value))<0)
+			throw new TInvalidDataValueException('pager_currentpageindex_invalid');
+		$this->setViewState('CurrentPageIndex',$value,0);
 	}
 
 	/**
-	 * Restores the pager from viewstate.
+	 * @return integer number of pages of data items available
 	 */
-	protected function restoreFromViewState()
+	public function getPageCount()
 	{
-		$this->reset();
-		$ds=$this->createPagedDataSource();
-		$ds->setDataSource(new TDummyDataSource($this->getItemCount()));
-		$this->buildPager($ds);
+		return $this->getViewState('PageCount',0);
+	}
+
+	/**
+	 * @param integer number of pages of data items available
+	 * @throws TInvalidDataValueException if the value is less than 0
+	 */
+	protected function setPageCount($value)
+	{
+		if(($value=TPropertyValue::ensureInteger($value))<0)
+			throw new TInvalidDataValueException('pager_pagecount_invalid');
+		$this->setViewState('PageCount',$value,0);
+	}
+
+	/**
+	 * @return boolean whether the current page is the first page Defaults to false.
+	 */
+	public function getIsFirstPage()
+	{
+		return $this->getCurrentPageIndex()===0;
+	}
+
+	/**
+	 * @return boolean whether the current page is the last page
+	 */
+	public function getIsLastPage()
+	{
+		return $this->getCurrentPageIndex()===$this->getPageCount()-1;
 	}
 
 	/**
@@ -390,66 +260,43 @@ class TPager extends TDataBoundControl implements INamingContainer
 	 * You may override this function to provide your own way of data population.
 	 * @param Traversable the bound data
 	 */
-	protected function performDataBinding($data)
+	public function onPreRender($param)
 	{
-		$this->reset();
+		parent::onPreRender($param);
 
 		$controlID=$this->getControlToPaginate();
 		if(($targetControl=$this->getNamingContainer()->findControl($controlID))===null || !($targetControl instanceof TDataBoundControl))
 			throw new TConfigurationException('pager_controltopaginate_invalid',$controlID);
 
-		$ds=$this->createPagedDataSource();
-		$ds->setDataSource($this->getDataSource());
-		$this->setViewState('ItemCount',$ds->getDataSourceCount());
-
-		$this->buildPager($ds);
-		$this->synchronizePagers($targetControl,$ds);
-
-		$targetControl->setDataSource($ds);
-		$targetControl->dataBind();
-	}
-
-	/**
-	 * Synchronizes the state of all pagers who have the same {@link getControlToPaginate ControlToPaginate}.
-	 * @param TDataBoundControl the control whose content is to be paginated
-	 * @param TPagedDataSource the paged data source associated with the pager
-	 */
-	protected function synchronizePagers($targetControl,$dataSource)
-	{
-		foreach(self::$_pagers as $pager)
+		if($targetControl->getAllowPaging() && $targetControl->getPageCount()>1)
 		{
-			if($pager!==$this && $pager->getNamingContainer()->findControl($pager->getControlToPaginate())===$targetControl)
-			{
-				$pager->reset();
-				$pager->setCurrentPageIndex($dataSource->getCurrentPageIndex());
-				$customPaging=$dataSource->getAllowCustomPaging();
-				$pager->setAllowCustomPaging($customPaging);
-				$pager->setViewState('ItemCount',$dataSource->getDataSourceCount());
-				if($customPaging)
-					$pager->setVirtualItemCount($dataSource->getVirtualItemCount());
-				$pager->buildPager($dataSource);
-			}
+			$this->setVisible(true);
+			$this->getControls()->clear();
+			$this->setPageCount($targetControl->getPageCount());
+			$this->setCurrentPageIndex($targetControl->getCurrentPageIndex());
+			$this->buildPager();
 		}
+		else
+			$this->setVisible(false);
 	}
 
 	/**
 	 * Builds the pager content based on the pager mode.
 	 * Current implementation includes building 'NextPrev', 'Numeric' and 'List' pagers.
 	 * Derived classes may override this method to provide additional pagers.
-	 * @param TPagedDataSource data source bound to the target control
 	 */
-	protected function buildPager($dataSource)
+	protected function buildPager()
 	{
 		switch($this->getMode())
 		{
 			case 'NextPrev':
-				$this->buildNextPrevPager($dataSource);
+				$this->buildNextPrevPager();
 				break;
 			case 'Numeric':
-				$this->buildNumericPager($dataSource);
+				$this->buildNumericPager();
 				break;
 			case 'List':
-				$this->buildListPager($dataSource);
+				$this->buildListPager();
 				break;
 		}
 	}
@@ -494,13 +341,12 @@ class TPager extends TDataBoundControl implements INamingContainer
 
 	/**
 	 * Builds a next-prev pager
-	 * @param TPagedDataSource data source bound to the pager
 	 */
-	protected function buildNextPrevPager($dataSource)
+	protected function buildNextPrevPager()
 	{
 		$buttonType=$this->getButtonType();
 		$controls=$this->getControls();
-		if($dataSource->getIsFirstPage())
+		if($this->getIsFirstPage())
 		{
 			if(($text=$this->getFirstPageText())!=='')
 			{
@@ -523,7 +369,7 @@ class TPager extends TDataBoundControl implements INamingContainer
 			$controls->add($button);
 		}
 		$controls->add("\n");
-		if($dataSource->getIsLastPage())
+		if($this->getIsLastPage())
 		{
 			$label=$this->createPagerButton($buttonType,false,$this->getNextPageText(),'','');
 			$controls->add($label);
@@ -549,14 +395,13 @@ class TPager extends TDataBoundControl implements INamingContainer
 
 	/**
 	 * Builds a numeric pager
-	 * @param TPagedDataSource data source bound to the pager
 	 */
-	protected function buildNumericPager($dataSource)
+	protected function buildNumericPager()
 	{
 		$buttonType=$this->getButtonType();
 		$controls=$this->getControls();
-		$pageCount=$dataSource->getPageCount();
-		$pageIndex=$dataSource->getCurrentPageIndex()+1;
+		$pageCount=$this->getPageCount();
+		$pageIndex=$this->getCurrentPageIndex()+1;
 		$maxButtonCount=$this->getPageButtonCount();
 		$buttonCount=$maxButtonCount>$pageCount?$pageCount:$maxButtonCount;
 		$startPageIndex=1;
@@ -620,15 +465,14 @@ class TPager extends TDataBoundControl implements INamingContainer
 
 	/**
 	 * Builds a dropdown list pager
-	 * @param TPagedDataSource data source bound to the pager
 	 */
-	protected function buildListPager($dataSource)
+	protected function buildListPager()
 	{
 		$list=new TDropDownList;
 		$this->getControls()->add($list);
-		$list->setDataSource(range(1,$dataSource->getPageCount()));
+		$list->setDataSource(range(1,$this->getPageCount()));
 		$list->dataBind();
-		$list->setSelectedIndex($dataSource->getCurrentPageIndex());
+		$list->setSelectedIndex($this->getCurrentPageIndex());
 		$list->setAutoPostBack(true);
 		$list->attachEventHandler('OnSelectedIndexChanged',array($this,'listIndexChanged'));
 	}