MyClass::ConstructL()
       {
       iMyCch = Cch::NewL();

       iMyService = iMyCch->GetService( iMyServiceId );

       User::LeaveIfNull( iMyService );

       iMyService->SetObserver( *this );

       TInt error = iMyService->Enable( iMyServiceType );

       if ( error != KErrNone )
           {
           User::Leave( error );
           }
       }

   MyClass::ServiceStatusChanged(
       TInt aServiceId,
       CCHSubserviceType aType,
       const TCchServiceStatus& aServiceStatus )
       {
       if ( aServiceStatus.Error() != KErrNone )
           {
           HandleError();
           }
       else
           {
           HandleStateChange();
           }
       }

   MyClass::~MyClass()
       {
       iMyService->Disable( iMyServiceType );
       delete iCch;
       }

Since

S60 v3.2