1 <?xml version="1.0" encoding="utf-8"?>

     2 <!-- Copyright (c) 2007-2010 Nokia Corporation and/or its subsidiary(-ies) All rights reserved. -->

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     4 "Eclipse Public License v1.0" which accompanies this distribution, 

     5 and is available at the URL "http://www.eclipse.org/legal/epl-v10.html". -->

     6 <!-- Initial Contributors:

     7     Nokia Corporation - initial contribution.

     8 Contributors: 

     9 -->

    10 <!DOCTYPE task

    11   PUBLIC "-//OASIS//DTD DITA Task//EN" "task.dtd">

    12 <task id="GUID-13D2B45C-3A2A-497A-8D6A-87BE34D1DE69" xml:lang="en"><title>Implement

    13 the observer functions</title><prolog><metadata><keywords/></metadata></prolog><taskbody>

    14 <context><p>An application can register as an observer of a view by implementing

    15 the following observer interfaces. Observers can register with the View Server

    16 as activation observers, deactivation observers or as generic observers.</p><table id="GUID-7159BD7C-6466-4CA8-9211-FD33273C9784">

    17 <tgroup cols="3"><colspec colname="col1"/><colspec colname="col2"/><colspec colname="col3"/>

    18 <thead>

    19 <row>

    20 <entry valign="top"><p>Interface</p></entry>

    21 <entry valign="top"><p>Notification</p></entry>

    22 <entry valign="top"><p>Method to override</p></entry>

    23 </row>

    24 </thead>

    25 <tbody>

    26 <row>

    27 <entry><p><codeph>MCoeViewActivationObserver </codeph></p></entry>

    28 <entry><p>View activation notification for the specified view.</p></entry>

    29 <entry><p><codeblock xml:space="preserve">IMPORT_C void NotifyNextActivation(TVwsViewId&amp; aViewId,  MCoeViewActivationObserver&amp; aViewActivationObserver)

    30 </codeblock></p></entry>

    31 </row>

    32 <row>

    33 <entry><p><codeph>MCoeViewActivationObserver </codeph></p></entry>

    34 <entry><p>View activation notification for any view registered with view server.</p></entry>

    35 <entry><p><codeblock xml:space="preserve">IMPORT_C void NotifyNextActivation(MCoeViewActivationObserver&amp; aViewActivationObserver)

    36 </codeblock></p></entry>

    37 </row>

    38 <row>

    39 <entry><p><codeph>MCoeViewDeactivationObserver </codeph></p></entry>

    40 <entry><p>View deactivation notification for the specified view.</p></entry>

    41 <entry><p><codeblock xml:space="preserve">IMPORT_C void NotifyNextDeactivation (TVwsViewId&amp; aViewId, MCoeViewDeactivationObserver&amp; aViewDeactivationObserver)

    42 </codeblock></p></entry>

    43 </row>

    44 <row>

    45 <entry><p><codeph>MCoeViewDeactivationObserver </codeph></p></entry>

    46 <entry><p>View deactivation notification for any view registered with view

    47 server.</p></entry>

    48 <entry><p><codeblock xml:space="preserve">IMPORT_C void NotifyNextDeactivation (MCoeViewDeactivationObserver&amp; aViewDeactivationObserver)

    49 </codeblock></p></entry>

    50 </row>

    51 </tbody>

    52 </tgroup>

    53 </table><p>The following code snippet shows implementing the <codeph>MCoeViewActivationObserver</codeph> observer

    54 interface class:</p><codeblock xml:space="preserve">/** 

    55 CMCoeViewActivationObserver  - implements the MCoeViewActivationObserver interface for notifications only

    56 */

    57 CMCoeViewActivationObserver* CMCoeViewActivationObserver::NewL()    

    58     {

    59     CMCoeViewActivationObserver* self=new( ELeave ) CMCoeViewActivationObserver();

    60     return self;

    61     }

    62 void CMCoeViewActivationObserver::HandleViewActivation( const TVwsViewId& aNewlyActivatedViewId,

    63                                                         const TVwsViewId& aViewIdToBeDeactivated )    

    64     {_

    65     LIT( Kmessage, "Notified MCoeViewActivationObserver::HandleViewActivation: Newly Active View: 0x%x - Deactivate 0x%x" )    

    66     INFO_PRINTF2( Kmessage, aNewlyActivatedViewId.iViewUid.iUid, aViewIdToBeDeactivated.iViewUid.iUid );

    67     }</codeblock></context>

    68 </taskbody></task>