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<task id="GUID-ADC42872-9A5B-50F2-8A33-6621A8F7C177" xml:lang="en"><title>Handling
Feature Notification </title><shortdesc>How to handle notification of changes to a feature using <codeph>RFeatureControl</codeph>. </shortdesc><prolog><metadata><keywords/></metadata></prolog><taskbody>
<context id="GUID-96D657EC-032D-535E-926A-924CB5D07324"><p>To handle notification
of changes to a feature using <xref href="GUID-F6AAAC24-4A62-383A-86C6-2E46335C3FD4.dita"><apiname>RFeatureControl</apiname></xref>, take the
following steps. </p><p/><p>  <xref href="GUID-623C4183-00F0-36B0-AE1F-5C5EDCAF1B3D.dita"><apiname>MFeatureObserver</apiname></xref> is an
interface which you implement to react to change notification in whatever
way you choose. It has two member functions which you must implement:   </p><p/><p><xref href="GUID-428DC6B1-6847-313F-BEEF-A8EC2442BA57.dita"><apiname>HandleNotifyChange()</apiname></xref> and</p><p><xref href="GUID-F737E1D7-5B67-345D-8290-E31F214D55E8.dita"><apiname>HandleNotifyError()</apiname></xref></p><p/><p>&lt;api-item&gt;HandleNotifyChange()&lt;/api-item&gt; takes two arguments: </p><p/><p>a <xref href="GUID-5F29338F-1073-3160-8FDD-E3FD4932F009.dita"><apiname>TFeatureChangeType</apiname></xref> representing
the kind of change you want to be notified of, and</p><p>a <xref href="GUID-80C51259-F2C4-3877-97B4-EC0C85DE93DE.dita"><apiname>TFeatureEntry</apiname></xref> object
representing the feature you want to be notified of when it is change. </p><p/><p> <xref href="GUID-F737E1D7-5B67-345D-8290-E31F214D55E8.dita"><apiname>HandleNotifyError()</apiname></xref> takes
one argument, an integer: this integer represents one of the Symbian platform
error codes. Any error in the notifier causes the notifier to stop handling
notifications. Your implementation should respond to each of the error types
you expect to occur.   </p> </context>
</taskbody><related-links>
<link href="GUID-2E33854B-5725-55DE-9B03-7A3100F5A5B5.dita"><linktext>Requesting
feature                 notification</linktext></link>
<link href="GUID-926862C4-5E13-5896-B959-0D408C748AB5.dita"><linktext>Cancelling
feature                 notification</linktext></link>
<link href="GUID-B71AC5E3-8AA8-55AD-916F-9E873926011B.dita"><linktext>Feature Manager
Collection Overview</linktext></link>
<link href="GUID-910780A3-D6AB-5EE2-966A-5F228AC5804F.dita"><linktext>Feature Manager
Notification Tutorials</linktext></link>
</related-links></task>