/*

* Copyright (c) 2005-2006 Nokia Corporation and/or its subsidiary(-ies). 

* All rights reserved.

* This component and the accompanying materials are made available

* which accompanies this distribution, and is available

*

* Initial Contributors:

* Nokia Corporation - initial contribution.

*

* Contributors:

*

* Description:  CPosLmItemIterator class

*

*/

#ifndef CPOSLMITEMITERATOR_H

#define CPOSLMITEMITERATOR_H

#include <e32base.h>

#include "EPos_Landmarks.h"

/**

*  Landmark item iterator.

*

*  This is an abstract base class for objects which iterates a set of database

*  items in a single database.

*

*  A database item is an item which is stored in a landmark database, i.e. a

*  landmark or a landmark category.

*

*  Note that an iterator either iterates categories or landmarks. The items are

*  never mixed.

*

*  This class does not export a constructor. The instance is created by the

*  operation which generates the item set to be iterated. The iterator may

*  implement a caching scheme, but that scheme depends on what is iterated.

*

*  @lib eposlandmarks.lib

*  @since S60 3.0

*/

class CPosLmItemIterator : public CBase

    {

    public:

        /**

        * Destructor.

        */

        IMPORT_C virtual ~CPosLmItemIterator();

    public:

        /**

        * Returns the next database item ID in the iterated set.

        *

        * The first call will return the first database item ID in the set.

        *

        * @return The next database item ID, or @p KPosLmNullItemId if there

        *   are no more database items in the iterated set.

        */

        virtual TPosLmItemId NextL() = 0;

        /**

        * Resets the database item iterator.

        *

        * The next call to @ref NextL will return the first database item ID in

        * the iterated set.

        */

        virtual void Reset() = 0;

        /**

        * Returns the number of database items which are iterated.

        *

        * @return Number of items in the iterated database item set.

        */

        virtual TUint NumOfItemsL() = 0;

        /**

        * Fetches a sequence of database items from the iterated set.

        *

        * The client supplies an ID array which will be filled by this

        * operation. The array will be reset before any items are added.

        *

        * The client specifies which database item sequence to fetch by

        * supplying a start index (0 is the first item) and the number of items

        * to fetch.

        *

        * @param[out] aIdArray On return contains the requested items.

        * @param[in] aStartIndex The index of the first item to fetch.

        * @param[in] aNumOfItems The number of items to fetch

        *

        * @panic "Landmarks Client"-EPosSpecifiedIntervalLiesOutsideIteratedSet 

        *   specified interval lies [partially] outside the iterated set.

        */

        virtual void GetItemIdsL(

            RArray<TPosLmItemId>& aIdArray,

            TInt aStartIndex,

            TInt aNumOfItems

        ) = 0;

    protected:

        // C++ constructor.

        IMPORT_C CPosLmItemIterator();

    private:

        // Prohibit copy constructor

        CPosLmItemIterator( const CPosLmItemIterator& );

        // Prohibit assigment operator

        CPosLmItemIterator& operator= ( const CPosLmItemIterator& );

    };

#endif      // CPOSLMITEMITERATOR_H