1 /*

     2 * Copyright (c) 2006 Nokia Corporation and/or its subsidiary(-ies).

     3 * All rights reserved.

     4 * This component and the accompanying materials are made available

     5 * under the terms of "Eclipse Public License v1.0"

     6 * which accompanies this distribution, and is available

     7 * at the URL "http://www.eclipse.org/legal/epl-v10.html".

     8 *

     9 * Initial Contributors:

    10 * Nokia Corporation - initial contribution.

    11 *

    12 * Contributors:

    13 *

    14 * Description:  Observer interface for the tree structure.

    15 *

    16 */

    17 

    18 

    19 #ifndef M_AKNTREEOBSERVER_H

    20 #define M_AKNTREEOBSERVER_H

    21 

    22 

    23 class CAknTree;

    24 class CAknTreeItem;

    25 

    26 

    27 /**

    28  *  Observer interface for the tree structure.

    29  *

    30  *  Observers of the tree are notified of changes in the tree structure

    31  *  through this interface with appropriate events.

    32  *

    33  *  @lib aknhlist.lib

    34  *  @since S60 v3.2

    35  */

    36 class MAknTreeObserver

    37     {

    38 

    39 public:

    40 

    41     /**  Tree events. */

    42     enum TEvent

    43         {

    44         /** New item is added to the tree. */

    45         EItemAdded,

    46         /** Item is moved to another location in tree. */

    47         EItemMoved,

    48         /** Item is about to be removed from the tree. Observers are notified

    49             with this event before the item is removed. */

    50         EItemRemoveBegin,

    51         /** Item is removed from the tree. */

    52         EItemRemoveEnd,

    53         /** Tree node is expanded. */

    54         ENodeExpanded,

    55         /** Tree node is collapsed. */

    56         ENodeCollapsed,

    57         /** Content of a item is changed (item need to be redrawn if visible). */

    58         EItemModified,

    59         /** Tree has been sorted. */

    60         ETreeSorted

    61         };

    62 

    63     /**

    64      * Notification of a tree event. The event is specified as a parameter.

    65      *

    66      * @param aEvent Tree event.

    67      *

    68      * @param aItem Pointer to the tree item that is concerned by the event.

    69      *

    70      * @param aDrawNow @c ETrue, if the view should be redrawn after the

    71      *      event.

    72      */

    73     virtual void HandleTreeEvent( TEvent aEvent, CAknTreeItem* aItem,

    74         TBool aDrawNow ) = 0;

    75 

    76     };

    77 

    78 

    79 #endif // M_AKNTREEOBSERVER_H