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<!DOCTYPE concept
  PUBLIC "-//OASIS//DTD DITA Concept//EN" "concept.dtd">
<concept id="GUID-4D2AA522-82AB-4D1E-9F1E-5C6A35DEF195" xml:lang="en"><title>Pointer
events</title><prolog><metadata><keywords/></metadata></prolog><conbody>
<p><draft-comment time="2007-02-26T14:58">Add some additional contextual
information and examples in a future release of the library.</draft-comment></p>
<p>Pointer events are handled by the controls. A control should implement
the function <xref href="GUID-F1BFA411-8316-314C-8E4A-C6140124CB58.dita"><apiname>CCoeControl:HandlePointerEventL()</apiname></xref>  to be able
to handle pointer events. The <xref href="GUID-F1BFA411-8316-314C-8E4A-C6140124CB58.dita"><apiname>CCoeControl:HandlePointerEventL()</apiname></xref> function
is called by the framework whenever a pointer event occurs within the control. </p>
<codeblock id="GUID-F12E88CC-31FF-4C26-8FEC-0BC2C7717907" xml:space="preserve">virtual void HandlePointerEventL(const TPointerEvent&amp; aPointerEvent);
</codeblock>
<p>Before passing pointer events to controls, the framework performs the
event processing. If a <xref href="GUID-1FFA0073-3D83-388E-A824-08C31F90CC54.dita#GUID-1FFA0073-3D83-388E-A824-08C31F90CC54/GUID-26CE2524-04BC-3592-A7E5-7EEC792A466E"><apiname>TPointerEvent::EButton1Down()</apiname></xref> event
occurred in the control and the control does not currently have keyboard focus,
it sends an event of type <xref href="GUID-A2BF9AE8-CF42-3D94-8763-66DB11EDDA46.dita#GUID-A2BF9AE8-CF42-3D94-8763-66DB11EDDA46/GUID-E1A96B7F-0AF1-3397-AA94-C55ED75B01EC"><apiname>MCoeControlObserver::EEventRequestFocus()</apiname></xref> to
the control's observer — normally the control's container. The container control
should then set focus onto the control in which the <xref href="GUID-1FFA0073-3D83-388E-A824-08C31F90CC54.dita#GUID-1FFA0073-3D83-388E-A824-08C31F90CC54/GUID-26CE2524-04BC-3592-A7E5-7EEC792A466E"><apiname>TPointerEvent::EButton1Down()</apiname></xref> event
occurred. </p>
<note>
<p>By default, pointer drag events and pointer move events are not delivered
to controls. For additional information, see functions <xref href="GUID-1460DD8F-9AA1-3B99-8FFD-F309959CCA34.dita#GUID-1460DD8F-9AA1-3B99-8FFD-F309959CCA34/GUID-175F4394-0747-3F42-9364-024B3C55E0A3"><apiname>RWindowBase::PointerFilter()</apiname></xref> and <xref href="GUID-B06F99BD-F032-3B87-AB26-5DD6EBE8C160.dita#GUID-B06F99BD-F032-3B87-AB26-5DD6EBE8C160/GUID-477F4BAA-268B-3F9F-9C18-6C6BF5403805"><apiname>CCoeControl::ClaimPointerGrab()</apiname></xref>.</p>
</note>
<p> The following code example demonstrates usage of the <parmname>TPointerEvent </parmname>class:</p>
<codeblock id="GUID-E050A4D7-995E-4819-B172-DCA432E3191F" xml:space="preserve">void CEventsAppView::HandlePointerEventL( const TPointerEvent&amp; aPointerEvent )
    {
    switch( aPointerEvent.iType )
        {
        case TPointerEvent::EButton1Down:
            {
            // Button 1 down
            // Get pointer position
            TPoint positionX = aPointerEvent.iPosition.iX;
            TPoint positionY = aPointerEvent.iPosition.iY;
            break;
            }
        case TPointerEvent::EButton1Up:
            {
            // button 1 up
            break;
            }
        case TPointerEvent::EDrag:
            {
            // drag event
            break;
            }
        case TPointerEvent::EMove:
            {
            // move event
            break;
            }
        default:
            {
            // do something
            break;
            }
        }
    }   </codeblock>
<p>For information on advanced pointer events, see <xref href="GUID-A12A66ED-2C8F-5CE6-8F3E-332B045A35B4.dita">Advanced
pointers</xref> section.</p>
</conbody></concept>