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

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

<p> When an event occurs under the window server, the framework calls the <xref href="GUID-3AC2CDAC-0291-309F-A020-049BC9F2CF90.dita#GUID-3AC2CDAC-0291-309F-A020-049BC9F2CF90/GUID-1ADF5125-A91A-3C5D-8422-50A84D7D6493"><apiname>CCoeAppUi::HandleWsEventL()</apiname></xref> function

of the UI controller object. To implement an event-handling code for a certain

event, <xref href="GUID-3AC2CDAC-0291-309F-A020-049BC9F2CF90.dita#GUID-3AC2CDAC-0291-309F-A020-049BC9F2CF90/GUID-1ADF5125-A91A-3C5D-8422-50A84D7D6493"><apiname>CCoeAppUi::HandleWsEventL()</apiname></xref> must be overridden.

To ensure that the system works correctly, after catching an event in the

overridden <xref href="GUID-3AC2CDAC-0291-309F-A020-049BC9F2CF90.dita#GUID-3AC2CDAC-0291-309F-A020-049BC9F2CF90/GUID-1ADF5125-A91A-3C5D-8422-50A84D7D6493"><apiname>CCoeAppUi::HandleWsEventL()</apiname></xref> function the base

class implementation should be called. The event type is identified by <parmname>TEventCode</parmname>,

which is a data member of the window server event, <parmname>TWsEvent</parmname>. </p>

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

</codeblock>

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

<note>

<p>Some event types are not implemented in the system or are not available

for third-party applications. All event codes from <xref href="GUID-420348F5-4A82-3780-9D27-A3E1F4780F0B.dita#GUID-420348F5-4A82-3780-9D27-A3E1F4780F0B/GUID-5FADC321-7A9E-3CF6-B59F-D142E7A2EFF4"><apiname>TEventCode::EEventUser()</apiname></xref> upwards

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

events</xref>).</p>

</note>

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

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

                               CCoeControl* aDestination )

    {

    // Call the base class implementation

    CEikAppUi::HandleWsEventL( aEvent, aDestination );

    if( aEvent.Type() == EEventKeyDown )

        {

        // Do something

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

        }

    }

</codeblock>

</conbody></concept>