Symbian3/PDK/Source/GUID-BBA7D3E2-1766-53CA-8D58-4F0B3BAA4873.dita
author Dominic Pinkman <dominic.pinkman@nokia.com>
Fri, 13 Aug 2010 16:47:46 +0100
changeset 14 578be2adaf3e
parent 5 f345bda72bc4
permissions -rw-r--r--
Week 32 contribution of PDK documentation content. See release notes for details. Fixes bug Bug 3582

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    Nokia Corporation - initial contribution.
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<!DOCTYPE task
  PUBLIC "-//OASIS//DTD DITA Task//EN" "task.dtd">
<task id="GUID-BBA7D3E2-1766-53CA-8D58-4F0B3BAA4873" xml:lang="en"><title>Registering
for Shutdown Notification</title><shortdesc>This document explains how to register for shutdown notification
for a component. </shortdesc><prolog><metadata><keywords/></metadata></prolog><taskbody>
<prereq><p>Before you start, you must know: </p> <ul>
<li id="GUID-5B8F2E24-2E7C-569E-9603-2775788DD9F3"><p>the APIs for components
that want to be system state aware. </p> </li>
<li id="GUID-E7336F6D-EDB1-5EB2-A2FD-9D28468EEC1C"><p>that each state aware
component must connect to the appropriate domain ID. </p> </li>
</ul> </prereq>
<context><p>Register a component or an application for shutdown notification
through <xref href="GUID-89C25B0F-DB76-30D5-A4D6-0C12922194E4.dita"><apiname>RSsmStateAwareSession</apiname></xref> if they need to do save critical
or non-critical data and perform clean-up tasks at the time of shutdown. </p> <p>For
example, a component or an application can free all resources or can close
any connection with the servers to make the shutdown graceful. The shutdown
sequence will commence once all the components acknowledge the notification
they have received. </p><p>Follow the steps given below to register for shutdown
notification:</p></context>
<steps id="GUID-70BB5BD2-EFB2-5E9E-BFE4-B57B9E6FB49B">
<step id="GUID-EA0AA697-4409-5587-BBC7-8E18EF7E0B6D"><cmd/>
<info>Create a class which is derived from <xref href="GUID-067293BF-B28C-3CEC-92F4-1351A795EA7F.dita"><apiname>CActive</apiname></xref>  </info>
<info>The following code snippet illustrates how to create a class from <xref href="GUID-067293BF-B28C-3CEC-92F4-1351A795EA7F.dita"><apiname>CActive</apiname></xref>: </info>
<stepxmp><codeblock id="GUID-C84D1F72-0FFE-5E2E-B34B-1325E905030C" xml:space="preserve">
class CExample : public CActive
{
    public:
          static CExample* NewL();
          ~CExample();

          private:
              //from CActive
              void RunL();
              void DoCancel();
          private:
              void ConstructL();
          private:
              RSsmStateAwareSession iStateAwareSession;
              //A state aware component, which can be used to provide APIs for components that want to be system state aware.
};
</codeblock> </stepxmp>
</step>
<step id="GUID-5D5E947F-A834-598C-9D13-D0D8C50F9B91"><cmd/>
<info>Connect the session and register for notification. </info>
<info>The following code snippet illustrates how to connect the session and
register for notification: </info>
<stepxmp><codeblock id="GUID-99CB04C9-838D-57A5-9154-39F739178FFC" xml:space="preserve">
CExample* CExample::NewL()
{
    CExample* self = new( ELeave ) CExample();
          CleanupStack::PushL( self );
          self-&gt;ConstructL();
          CleanupStack::Pop( self );
          return self;
}
CExample:: CExample()
CActive( CActive::EPriorityStandard )
{
    CActiveScheduler::Add( this );
}
void CExample::ConstructL()
{
    // Each state aware component must connect to the appropriate domain ID.
    //Example, this component is high up in the domain hierarchy ( in the UI Frameworks domain ).
    User::LeaveIfError( iStateAwareSession.Connect ( KUIFramework3 ));
          iStateAwareSession.RequestStateNotification( iStatus );
          SetActive();
}</codeblock> </stepxmp>
</step>
</steps>
<result><p>The component is registered for shutdown notification. </p> </result>
<postreq><p>After registering for shutdown notification, the user needs to
know how the component handles and acknowledge the shutdown notification. </p> </postreq>
</taskbody><related-links>
<link href="GUID-833BF27D-B288-506A-B545-E748C9FE7AEA.dita"><linktext>Making a
Component Shutdown Aware</linktext></link>
</related-links></task>