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, 

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     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-3729C075-4958-4874-9DD7-02A68D17E043" xml:lang="en"><title>Other

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

    14 <p> When an event occurs under the window server, the framework calls the <xref href="jar:GUID-35228542-8C95-4849-A73F-2B4F082F0C44.jar!/sdk/doc_source/reference/reference-cpp/Control_Environment/CCoeAppUiClass.html#%3a%3aCCoeAppUi%3a%3aHandleWsEventL%28const%20TWsEvent%20%26amp%3b%2cCCoeControl%20%2a%29" format="application/java-archive"><parmname>HandleWsEventL()</parmname></xref> function of the UI controller

    15 object. To implement an event-handling code for a certain event, <xref href="jar:GUID-35228542-8C95-4849-A73F-2B4F082F0C44.jar!/sdk/doc_source/reference/reference-cpp/Control_Environment/CCoeAppUiClass.html#%3a%3aCCoeAppUi%3a%3aHandleWsEventL%28const%20TWsEvent%20%26amp%3b%2cCCoeControl%20%2a%29" format="application/java-archive"><parmname>HandleWsEventL()</parmname></xref> must be overridden. In

    16 order to ensure that the system works correctly, after catching an event in

    17 the overridden <xref href="jar:GUID-35228542-8C95-4849-A73F-2B4F082F0C44.jar!/sdk/doc_source/reference/reference-cpp/Control_Environment/CCoeAppUiClass.html#%3a%3aCCoeAppUi%3a%3aHandleWsEventL%28const%20TWsEvent%20%26amp%3b%2cCCoeControl%20%2a%29" format="application/java-archive"><parmname>HandleWsEventL()</parmname></xref> function the base class

    18 implementation should be called. The event type is identified by <xref href="jar:GUID-35228542-8C95-4849-A73F-2B4F082F0C44.jar!/sdk/doc_source/reference/reference-cpp/Window_Server/W32STD.HGlobals.html#%3a%3aTEventCode" format="application/java-archive"><parmname>TEventCode</parmname></xref>, which is a data member of the

    19 window server event, <xref href="jar:GUID-35228542-8C95-4849-A73F-2B4F082F0C44.jar!/sdk/doc_source/reference/reference-cpp/Window_Server/TWsEventClass.html#_top%20title=" format="application/java-archive"><parmname>TWsEvent</parmname></xref>. </p>

    20 <codeblock id="GUID-C3C94D39-9BDF-4F89-9DEE-B1078A2AD04E" xml:space="preserve">void HandleWsEventL( const TWsEvent&amp; aEvent, CCoeControl* aDestination )

    21 </codeblock>

    22 <p> All the event types are defined in the <parmname>w32std.h</parmname> header.</p>

    23 <p>Note that some event types are not implemented in the system or are

    24 not available for third-party applications. All event codes from <xref href="jar:GUID-35228542-8C95-4849-A73F-2B4F082F0C44.jar!/sdk/doc_source/reference/reference-cpp/Window_Server/W32STD.HGlobals.html#%3a%3aTEventCode" format="application/java-archive"><parmname>TEventCode:EEventUser</parmname></xref> upwards can be used

    25 for the application-specific events (discussed in <xref href="GUID-95DD1440-01C9-4997-8DD4-FFD33D7DEAFF.dita">Application-specific

    26 events</xref>).

    27 The following is a code example of the usage of a window server event:</p>

    28 <codeblock id="GUID-CF247807-C0BF-4C84-B8DF-8C636F895043" xml:space="preserve">void CMyAppUi::HandleWsEventL( const TWsEvent&amp; aEvent,

    29                                CCoeControl* aDestination )

    30     {

    31     // Call the base class implementation

    32     CEikAppUi::HandleWsEventL( aEvent, aDestination );

    33     if( aEvent.Type() == EEventKeyDown )

    34         {

    35         // Do something

    36         iEikonEnv->InfoMsg( _L( “Key was pressed” ) );

    37         }

    38     }

    39 </codeblock>

    40 </conbody></concept>