sl@0: /*
sl@0: * Copyright (c) 2004 Nokia Corporation and/or its subsidiary(-ies). 
sl@0: * All rights reserved.
sl@0: * This component and the accompanying materials are made available
sl@0: * under the terms of "Eclipse Public License v1.0"
sl@0: * which accompanies this distribution, and is available
sl@0: * at the URL "http://www.eclipse.org/legal/epl-v10.html".
sl@0: *
sl@0: * Initial Contributors:
sl@0: * Nokia Corporation - initial contribution.
sl@0: *
sl@0: * Contributors:
sl@0: *
sl@0: * Description:  This is the definition of the audio effects base class.
sl@0: *
sl@0: *
sl@0: */
sl@0: 
sl@0: 
sl@0: #ifndef CAUDIOEFFECT_H
sl@0: #define CAUDIOEFFECT_H
sl@0: 
sl@0: // INCLUDES
sl@0: #include <e32base.h>
sl@0: 
sl@0: // FORWARD DECLARATION
sl@0: class MAudioEffectObserver;
sl@0: 
sl@0: // CLASS DECLARATION
sl@0: 
sl@0: /**
sl@0: *  This is the base class for audio effects.
sl@0: *
sl@0: *  @lib AudioEffectBase.lib
sl@0: *  @since 3.0
sl@0: */
sl@0: 
sl@0: class CAudioEffect : public CBase
sl@0: 	{
sl@0: 
sl@0: 	public: // Constructors and destructor
sl@0: 
sl@0: 		/**
sl@0:         *	Destructor
sl@0:         */
sl@0: 		IMPORT_C virtual ~CAudioEffect();
sl@0: 
sl@0:     public: // New functions
sl@0: 
sl@0: 		/**
sl@0:         * Apply effect settings
sl@0:         * @since 3.0
sl@0:         */
sl@0: 		virtual void ApplyL() = 0;
sl@0: 
sl@0: 		/**
sl@0:         * Disable the effect
sl@0:         * @since 3.0
sl@0:         */
sl@0: 		IMPORT_C virtual void DisableL();
sl@0: 
sl@0: 		/**
sl@0:         * Enable the effect
sl@0:         * @since 3.0
sl@0:         */
sl@0: 		IMPORT_C virtual void EnableL();
sl@0: 
sl@0: 		/**
sl@0:         * Enforce the effect.
sl@0:         * @since 3.0
sl@0:         * @param aEnforced Indicate the effect is to be enforced or not. ETrue = Enforced.
sl@0:         */
sl@0: 		IMPORT_C virtual void EnforceL( TBool aEnforced );
sl@0: 
sl@0: 		/**
sl@0:         * Check if this effect object currently has update rights.
sl@0:         * A client can lose update rights in some hardware platforms where there are a limited
sl@0:         * number of instances of an effect that can exist at the same time. When an effect instance
sl@0:         * has lost update rights the user can still change settings, but any calls to Apply the
sl@0:         * settings will be deferred until update rights are regained.
sl@0:         * @since 3.0
sl@0:         * @return ETrue if this object currently has rights to update the settings of this effect,
sl@0:         *         EFalse otherwise.
sl@0:         */
sl@0: 		IMPORT_C virtual TBool HaveUpdateRights() const;
sl@0: 
sl@0: 		/**
sl@0:         * Check if the effect is enabled
sl@0:         * @since 3.0
sl@0:         * @return ETrue if the effect is enabled, EFalse if the effect is disabled.
sl@0:         */
sl@0: 		IMPORT_C virtual TBool IsEnabled() const;
sl@0: 
sl@0: 		/**
sl@0:         * Check if the effect is enforced.
sl@0:         * @since 3.0
sl@0:         * @return ETrue if the effect is enforced, EFalse if the effect isn ot enforced.
sl@0:         */
sl@0: 		IMPORT_C virtual TBool IsEnforced() const;
sl@0: 
sl@0: 		/**
sl@0:         * Adds the specified observer to the list of observers to be notified when
sl@0:         * the effect object changes state.
sl@0:         * @since 3.0
sl@0:         * @param aObserver Object to be added to notifier list.
sl@0:         */
sl@0: 		IMPORT_C void RegisterObserverL( MAudioEffectObserver& aObserver );
sl@0: 
sl@0: 		/*
sl@0:         * Get the unique identifier of the audio effect
sl@0:         * @since 3.0
sl@0:         * @return Unique identifier of the audio effect object.
sl@0:         */
sl@0: 		virtual TUid Uid() const = 0 ;
sl@0: 
sl@0: 		/**
sl@0:         * Removes the specified observer from the list of observers.
sl@0:         * @since 3.0
sl@0:         * @param aObserver object to be removed.
sl@0:         */
sl@0: 		IMPORT_C void UnRegisterObserver( MAudioEffectObserver& aObserver );
sl@0: 
sl@0: 	protected:
sl@0: 
sl@0: 		/**
sl@0: 		* Private C++ constructor for this class.
sl@0:         * @since 3.0
sl@0:         * @param aEffectObserver	reference to event observer object
sl@0:         * @return -
sl@0:         */
sl@0: 		IMPORT_C CAudioEffect();
sl@0: 
sl@0: 		/**
sl@0: 		* Internal function to package data into a descriptor.
sl@0:         * @since 3.0
sl@0:         * @return A descriptor containing the effect data.
sl@0:         */
sl@0: 		virtual const TDesC8& DoEffectData() = 0 ;
sl@0: 
sl@0: 		/**
sl@0: 		* Internal function to unpack effect data
sl@0:         * @since 3.0
sl@0:         * @param aEffectDataBuffer Descriptor containing packed effect data
sl@0:         */
sl@0:         virtual void SetEffectData( const TDesC8& aEffectDataBuffer ) = 0;
sl@0: 
sl@0: 	protected: // Data
sl@0: 
sl@0: 		// Flag to indicate whether the effect is enabled or not
sl@0: 		TBool iEnabled;
sl@0: 		// Flag to indicate wheter the effect is enforced
sl@0: 		TBool iEnforced;
sl@0: 		// Flag to indicate wheter the effect current has update rights
sl@0: 		TBool iHaveUpdateRights;
sl@0: 		// Pointer to Observers
sl@0: 		RPointerArray<MAudioEffectObserver> iObservers;
sl@0: 	};
sl@0: 
sl@0: #endif	// of CAUDIOEFFECT_H
sl@0: 
sl@0: // End of File