/*
* Copyright (c) 2003 Nokia Corporation and/or its subsidiary(-ies).
* All rights reserved.
* This component and the accompanying materials are made available
* under the terms of "Eclipse Public License v1.0"
* which accompanies this distribution, and is available
* at the URL "http://www.eclipse.org/legal/epl-v10.html".
*
* Initial Contributors:
* Nokia Corporation - initial contribution.
*
* Contributors:
*
* Description: This file contains the header file of the Cmcn class.
*
* This header file presents an API which allows a client to
* subscribe a number of CB topics from CbsServer. The client
* receives a notification, if a message belonging to a subscribed
* topic is received.
*
*/
#ifndef CMCN_H
#define CMCN_H
// INCLUDES
#include "e32base.h"
#include <rcbsmcnsession.h>
// CONSTANTS
// Maximum length of a MCN message.
const TInt KCbsMcnMessageMaxLength = 93;
// DATA TYPES
typedef TBuf< KCbsMcnMessageMaxLength > TMcnMessage;
// FORWARD DECLARATIONS
class MCbsMcnObserver;
class CCbsMcnListener;
class RCbsMcnSession;
class CMcnTopicArray;
// CLASS DECLARATION
/**
* Client must first connect to the server and then register
* a MCbsMcnObserver-derived class to receive notifications
* when MCN messages are received from the network.
*
* Registration to CbsServer is not required to retrieve
* the current cell info message.
*
* In the example below, the client has implemented the class MCbsMcnObserver
* in class CCbsMcnObserver. First, the client establishes a session
* with CbsServer. The subscribed topics are specified with a CMcnTopicArray
* instance.
*
* Example:
*
* // Establish the session.
* CMcn* session = CMcn::NewL();
* CleanupStack::PushL( session );
*
* // Specify topics with CMcnTopicArray.
* CMcnTopicArray* topics = CMcnTopicArray::NewL();
* topics->AddCbTopicL( 50 ); // District info (cell info)
* topics->AddCbTopicL( 0 ); // CB index messages
*
* // Register. Parameter observer is an instance of CCbsMcnObserver.
* session->RegisterL( observer, topics );
* delete topics;
*
* // Get current MCN state.
* TMcnMessage mcnInfo;
* TInt result( session->GetCellInfo( mcnInfo ) );
* if ( result != KErrNone )
* {
* // mcnInfo contains the current MCN message.
* }
*
* // Observer's CellInfoChanged() gets called if MCN state changes.
* // Note that the active scheduler must be running here.
*
* // Terminate session.
* session->Unregister( observer );
* CleanupStack::PopAndDestroy(); // session, gets closed when deleted
*
*/
class CMcn
: public CBase
{
public: // New functions
/**
* Instantiates new CMcn object and establishes a session with
* CBS server.
*
* If connecting to CBS server fails, the function leaves with
* the leave code of RSessionBase::CreateSession().
*
* Active scheduler has to be installed prior to calling this function.
*
* @return A new instance of CMcn
*/
IMPORT_C static CMcn* NewL();
/**
* Destructor. Also closes CbsServer session.
*/
IMPORT_C ~CMcn();
/**
* Registers an observer to CBS server. The observer is notified when
* a MCN message is received from the network.
* The caller is also required to provide an array containing numbers
* of subscribed topics.
*
* Parameter aArray may contain topic number entry duplicates.
* Topics may be in any order.
*
* Leave codes indicate an error accessing EPOC Telephony Sever.
* In this case, the leave code is the same returned by EPOC Telephony Sever.
*
* @param aObserver Observer implemented by the client
* @param aArray List of relayed topics
*/
IMPORT_C void RegisterL( MCbsMcnObserver* aObserver,
const CMcnTopicArray& aArray );
/**
* Unregisters a previously registered MCN observer clearing
* any topic subscriptions of this client in CBS server.
*
* Panics if the observer specified was not registered.
*
* @param aObserver Observer implemented by the client
*/
IMPORT_C void Unregister( MCbsMcnObserver* aObserver );
/**
* Retrieves the current MCN message (Cell Info, topic 050) from CBS
* server. A new MCN message always overwrites the previous one in CBS
* server, no buffering is done. Note that this function may be
* only used to retrieve cell info messages.
*
* Return codes:
* KErrNone aMcnMessage contains the current, valid MCN message.
* KErrNotFound CbsServer has not yet received a MCN message.
* Content of aMcnMessage must be ignored.
*
* @param aMcnMessage Returns the current MCN message.
* @return Result code
*/
IMPORT_C TInt GetCellInfo( TDes& aMcnMessage ) const;
private: // new functions
/**
* Default constructor.
*/
CMcn();
/**
* 2nd-phase constructor
*/
void ConstructL();
/**
* Relays aMcnMessage to the registered observers.
* Used by a friend class CCbsMcnListener instance
*
* @param aMcnMessage Received CB message from CbsServer
*/
void RelayMessage( TCbsMcnMessage& aMcnMessage );
private: // friend classes
/// Allows use of RelayMessageL().
friend class CCbsMcnListener;
private: // prohibited functions and operators
/// Copy constructor.
CMcn( const CMcn& );
/// Assignment operator
CMcn& operator=( const CMcn& );
private: // Data
/**
* Own: Active object responsible for responding to server-initiated
* notification indicating that a message has arrived from
* the CbsServer.
*/
CCbsMcnListener* iMcnListener;
/// Own: Dynamic array containing the registered observers.
CArrayPtrFlat< MCbsMcnObserver >* iObservers;
/// CbsServer session object.
RCbsMcnSession iSession;
public:
/**
* Retrieves the current info message (e.g. HomeZone, topic 221) from CBS
* server. A new info message always overwrites the previous one in CBS
* server, no buffering is done. Note that this function may be
* only used to retrieve cell info messages.
*
* Return codes:
* KErrNone aInfoMessage contains the current, valid info message.
* KErrNotFound CbsServer has not yet received a info message.
* Content of aInfoMessage must be ignored.
*
* @param aInfoMessage Returns the current info message.
* @param aTopicNumber Number of the topic
* @return Result code
*/
IMPORT_C TInt GetInfoMessage( TDes& aInfoMessage, TInt aTopicNumber ) const;
};
#endif // CMCN_H
// End of File