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

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

     3 <!-- This component and the accompanying materials are made available under the terms of the License 

     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 concept

    11   PUBLIC "-//OASIS//DTD DITA Concept//EN" "concept.dtd">

    12 <concept id="GUID-868C1A38-3CD0-4082-8106-DC3EE1F815D8" xml:lang="en"><title>System

    13 events</title><prolog><metadata><keywords/></metadata></prolog><conbody>

    14 <p>System events are enumerated in <xref href="GUID-95954F7F-E214-309C-AF32-3A9BD77BDC31.dita"><apiname>TApaSystemEvent</apiname></xref>,

    15 which is defined in the <parmname>apgtask.h</parmname>. You must override <xref href="GUID-92361912-7768-3D2C-835E-BD3EF1366D6D.dita#GUID-92361912-7768-3D2C-835E-BD3EF1366D6D/GUID-71190B7E-A39E-3F20-A0D6-A519776A1480"><apiname>CCoeAppUI::HandleSystemEventL()</apiname></xref> to

    16 handle these events, which should be done in the UI controller. The default

    17 implementation is empty. The possible events are as follows:</p>

    18 <codeblock id="GUID-F0606F71-729A-4D6B-AAC6-876A526DDFAC" xml:space="preserve">enum TApaSystemEvent

    19     {

    20     EApaSystemEventShutdown = 1,

    21     EApaSystemEventBackupStarting,

    22     EApaSystemEventBackupComplete,

    23     EApaSystemEventBroughtToForeground

    24     };

    25 </codeblock>

    26 <p>The following is a code example of system event handling:</p>

    27 <codeblock id="GUID-86877508-AD28-4576-B9D5-55565B0F4A4A" xml:space="preserve">void CExampleAppUI::HandleSystemEvent( const TWsEvent&amp; aEvent )

    28     {

    29     switch( *( TApaSystemEvent* )( aEvent.EventData() ) )

    30         {

    31         case EApaSystemEventBackupStarting:

    32             {

    33             // Handle backup starting

    34             //...

    35             break;

    36             }

    37         case EApaSystemEventBackupComplete:

    38             {

    39             // Handle backup complete

    40             //...

    41             break;

    42             }

    43         case EApaSystemEventShutdown:

    44             {

    45             // Handle shutdown

    46             //...

    47             break;

    48             }

    49         }

    50         // Call the base class implementation

    51         CAknAppUi::HandleSystemEvent( aEvent );

    52     }

    53 </codeblock>

    54 </conbody></concept>