Addition of the PDK content and example code for Documentation_content according to Feature bug 1607 and bug 1608
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<!DOCTYPE concept
PUBLIC "-//OASIS//DTD DITA Concept//EN" "concept.dtd">
<concept id="GUID-11FE772A-E662-4B88-B871-97A40A40FBAB" xml:lang="en"><title>Handling
EEikCmdExit</title><prolog><metadata><keywords/></metadata></prolog><conbody>
<p>If your Symbian GUI-based application should close, for example, in
out of memory situations, you must handle the <parmname>EEikCmdExit</parmname> command
ID in your override of <xref href="jar:GUID-35228542-8C95-4849-A73F-2B4F082F0C44.jar!/sdk/doc_source/reference/reference-cpp/UIKON/CEikAppUiClass.html#%3a%3aCEikAppUi%3a%3aHandleCommandL%28%29" format="application/java-archive"><parmname>CEikAppUi::HandleCommandL</parmname></xref>. The UI architecture of your application determines where you
override <xref href="jar:GUID-35228542-8C95-4849-A73F-2B4F082F0C44.jar!/sdk/doc_source/reference/reference-cpp/UIKON/CEikAppUiClass.html#%3a%3aCEikAppUi%3a%3aHandleCommandL%28%29" format="application/java-archive"><parmname>CEikAppUi::HandleCommandL</parmname></xref>. A typical implementation
is as follows:</p>
<codeblock id="GUID-80E7C5FF-A507-42FA-ACF0-808539FFF6A5" xml:space="preserve">void CMyCommandHandlingAppUi::HandleCommandL(TInt aCommand)
{
switch(aCommand)
{
case EEikCmdExit:
case EAknSoftkeyExit:
Exit();
break;
default:
break;
}
}
</codeblock>
<p>where <xref href="jar:GUID-35228542-8C95-4849-A73F-2B4F082F0C44.jar!/sdk/doc_source/reference/reference-cpp/UIKON/CEikAppUiClass.html#%3a%3aCEikAppUi%3a%3aExit%28%29" format="application/java-archive"><parmname>CEikAppUI::Exit()</parmname></xref> closes the application. <xref href="jar:GUID-35228542-8C95-4849-A73F-2B4F082F0C44.jar!/sdk/doc_source/reference/reference-cpp/UIKON/CEikAppUiClass.html#%3a%3aCEikAppUi" format="application/java-archive"><parmname>CEikAppUI</parmname></xref> also provides <xref href="jar:GUID-35228542-8C95-4849-A73F-2B4F082F0C44.jar!/sdk/doc_source/reference/reference-cpp/UIKON/CEikAppUiClass.html#%3a%3aCEikAppUi%3a%3aSaveAnyChangesL%28%29" format="application/java-archive"><parmname>SaveAnyChangesL</parmname></xref> and <xref href="jar:GUID-35228542-8C95-4849-A73F-2B4F082F0C44.jar!/sdk/doc_source/reference/reference-cpp/UIKON/CEikAppUiClass.html#%3a%3aCEikAppUi%3a%3aSaveL%28%29" format="application/java-archive"><parmname>SaveL</parmname></xref> methods
in case you need to save the application document.</p>
<note>
<p>In Symbian view architecture applications, the <parmname>EEikCmdExit</parmname> command
must be only handled once: either in the UI controller or in a view. Since
the exit command is an application wide command, it is recommended that it
be handled in the UI controller implementation.</p>
</note>
<p><xref href="jar:GUID-35228542-8C95-4849-A73F-2B4F082F0C44.jar!/sdk/doc_source/reference/reference-cpp/UIKON/CEikAppUiClass.html#%3a%3aCEikAppUi%3a%3aExit%28%29" format="application/java-archive"><parmname>CEikAppUI::Exit()</parmname></xref> exits the application.
If the application is embedded, control returns to the parent, which should
also exit. The application framework sends an <parmname>EEikCmdExit</parmname> command
ID to each application in this chain to support this behavior.</p>
<note>
<p><xref href="jar:GUID-35228542-8C95-4849-A73F-2B4F082F0C44.jar!/sdk/doc_source/reference/reference-cpp/UIKON/CEikAppUiClass.html#%3a%3aCEikAppUi%3a%3aExit%28%29" format="application/java-archive"><parmname>CEikAppUI::Exit()</parmname></xref> is guaranteed not to
return. This means that you should not trap this method. Among other things,
do not call another method when you handle the command ID that triggers an
exit.</p>
</note>
</conbody></concept>