1 eikedwob.h

     1 /*

     2 * Copyright (c) 1997-1999 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 the License "Symbian Foundation License v1.0" to Symbian Foundation members and "Symbian Foundation End User License Agreement v1.0" to non-members

     6 * which accompanies this distribution, and is available

     7 * at the URL "http://www.symbianfoundation.org/legal/licencesv10.html".

     8 *

     9 * Initial Contributors:

    10 * Nokia Corporation - initial contribution.

    11 *

    12 * Contributors:

    13 *

    14 * Description:

    15 *

    16 */

    17 

    18 

    19 #if !defined(__EIKEDWOB_H__)

    20 #define __EIKEDWOB_H__

    21 

    22 class CEikEdwin;

    23 

    24 /**

    25  * Interface class describing the functionality expected of an observer

    26  * for CEikEdwins.

    27  * 

    28  * Edwin observers are informed by the edwin whenever its content is

    29  * changed, or whenever the user changes the cursor position.

    30  * 

    31  * This class should be derived from by all observers of edwins.

    32  */

    33 class MEikEdwinObserver

    34 	{

    35 public:

    36     /**

    37      * Events from a value editor.

    38      */

    39 	enum TEdwinEvent

    40 		{

    41 		/** Sent whenever the content of the edwin changes. */

    42 		EEventFormatChanged,

    43 		/** Sent on receipt of a navigation command. */

    44 		EEventNavigation,

    45 		/**

    46 		 * Sent whenever the text of the edwin changes. To observe

    47 		 * actual changes in the contents of the editor this should

    48 		 * be preferred to EEventFormatChanged.

    49 		 */

    50 		EEventTextUpdate,

    51 		/** Sent on receipt of a scroll event. */

    52 		EEventScroll,

    53 		/** Sent if you explicitly call edwin's SetTextL() */

    54 		EEventTextUpdateAPI

    55 		};

    56 public:

    57     /**

    58      * This pure virtual function is invoked by CEikEdwin to report an event

    59      * to its observer. The observer may respond appropriately.

    60      * 

    61      * @param aEdwin  The originating edwin. 

    62      * @param aEventType  The event being reported. 

    63      */

    64 	virtual void HandleEdwinEventL(CEikEdwin* aEdwin,TEdwinEvent aEventType)=0;

    65 	};

    66 

    67 /**

    68  * Interface to handle changes to an edwin's size.

    69  */

    70 class MEikEdwinSizeObserver

    71 	{

    72 public:

    73     /**

    74      * Specifies the type of event reported to the edwin observer.

    75      */

    76 	enum TEdwinSizeEvent

    77 		{

    78 		/**

    79 		 * Specifies a change in edwin size. When the edwin observer

    80 		 * receives an event of this type, it handles it by making

    81 		 * its view bigger or smaller according to the new edwin size.

    82 		 */

    83 		EEventSizeChanging

    84 		};

    85 public:

    86     /**

    87      * Handles a change in the edwin's size. If you implement this function,

    88      * ensure it returns ETrue if you wish to redraw the edwin.

    89      * 

    90      * @param aEdwin The edwin for which the size event is being handled.

    91      * @param aEventType The event type.

    92      * @param aDesirableEdwinSize The desired size for the edwin identified

    93      * by aEdwin.

    94      * @return The return value depends on your implementation. Return

    95      * ETrue if you wish to redraw the edwin. EFalse otherwise.

    96      */

    97 	virtual TBool HandleEdwinSizeEventL(CEikEdwin* aEdwin, TEdwinSizeEvent aEventType, TSize aDesirableEdwinSize)=0;

    98 	};

    99 

   100 #endif