Hierarchical Lists API - as the name suggests, provides an interface for end user applications to present data structures in a hierarchical list format available since S60 Release 5.0 and onwards.

CAknSingleStyleTreeList

- Single style hierarchical list.

Header & Library

#include <aknsinglestyletreelist.h>
 
LIBRARY aknhlist.lib

Capabilities

Capabilities - None
 
Code can be Self Signed.

Creating CAknSingleStyleTreeList

// where iTreeList is CAknSingleStyleTreeList*
iTreeList = CAknSingleStyleTreeList::NewL();
iTreeList->SetRect(aRect);

Adding Items

void CListExample::ConstructTreeL()
	{
	_LIT( KParentNode, "Node" );
	_LIT( KSubNode, "SubNode" );
	_LIT( KLeaf1, "Leaf1" );
	_LIT( KLeaf2, "Leaf2" );
 
 
	// Prepare Node 
	TUint32 flags1 = CAknSingleStyleTreeList::EPersistent;
	TAknTreeItemID mainNode = iTreeList->AddNodeL( KAknTreeIIDRoot, KParentNode,
			flags1, EFalse );
 
        // Add leaf to Main Node
	TAknTreeItemID leaf1 = iTreeList->AddLeafL( mainNode, KLeaf1, flags1, EFalse );
 
 
        // Setting it to expanded by default
	TUint32 flags2 = CAknSingleStyleTreeList::EExpanded;
	// Add another Node under Main Node
	TAknTreeItemID subNode = iTreeList->AddNodeL( mainNode, KSubNode,
			flags2, EFalse );
 
	// Add Leaf to sub node
	TAknTreeItemID leaf2 = iTreeList->AddLeafL( subNode, KLeaf2, flags2, EFalse );
	}

Removing Item

// Removing SubNode
iTreeList->RemoveItem( subNode );

Update Item

// Changing title for Main Node  //
iTreeList->SetTextL(mainNode, KSomeText, EFalse );

Registering for List Events

/*
* Notifications of common hierarhicial list events are sent to the list client through 
* MAknTreeListObserver.
*/
class CListExample : public CCoeControl, public MAknTreeListObserver
	{
public:
	....
 
	/**
	 * From MAknTreeListObserver
	 * Notifications of common hierarhicial list events.
	 */
	TInt  HandleTreeListEvent (CAknTreeList &aList, TAknTreeItemID aItem, TEvent aEvent);
 
	....
        }

/**
* Register for receiving list events passing MAknTreeListObserver* (i.e CListExample* 
* which * already implements MAknTreeListObserver 
*/
iTreeList->AddObserverL( this );

CAknSingleColumnStyleTreeList

- Single style hierarchical column list.

Header & Library

#include <aknsinglecolumnstyletreelist.h> 
 
LIBRARY aknhlist.lib

Capabilities

Capabilities - None
 
Code can be Self Signed.

Creating CAknSingleColumnStyleTreeList

// where iTreeList is CAknSingleColumnStyleTreeList*
iTreeList = CAknSingleColumnStyleTreeList::NewL();
iTreeList->SetRect(aRect);

Adding Items

void CListExample::ConstructTreeL()
	{
	_LIT( KParentNode, "Node" );
	_LIT( KSubNode, "SubNode" );
	_LIT( KLeaf1, "Leaf1" );
	_LIT( KLeaf2, "Leaf2" );
 
 
	// Prepare Node 
	TUint32 flags1 = CAknSingleColumnStyleTreeList::EPersistent;
	TAknTreeItemID mainNode = iTreeList->AddSubtitleRowL( KAknTreeIIDRoot, KParentNode,
			flags1, EFalse );
 
        // Add leaf to Main Node
	TAknTreeItemID leaf1 = iTreeList->AddSimpleDataRowL( mainNode, KLeaf1, NULL, EFalse );
 
 
        // Setting it to expanded by default
	TUint32 flags2 = CAknSingleColumnStyleTreeList::EExpanded;
 
	// Add another Node under Main Node
	TAknTreeItemID subNode = iTreeList->AddSubtitleRowL( mainNode, KSubNode,
			flags2, EFalse );
 
	// Add Leaf to sub node
	TAknTreeItemID leaf2 = iTreeList->AddSimpleDataRowL( subNode, KLeaf2, NULL, EFalse);
	}

Removing Item

// Removing SubNode
iTreeList->RemoveItem( subNode );

Update Item

// Changing title for Main Node  //
iTreeList->SetTextL(mainNode, KSomeText, EFalse );

Registering for List Events

/*
* Notifications of common hierarhicial list events are sent to the list client through 
* MAknTreeListObserver.
*/

Done in the similar manner as shown above for CAknSingleStyleTreeList.

/**
* Register for receiving list events passing MAknTreeListObserver* (i.e CListExample* 
* which * already implements MAknTreeListObserver 
*/
iTreeList->AddObserverL( this );

Facts & Constraints

- List cannot be constructed from resources.

- List can be created as both window-owning and non-window-owning.