--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mulwidgets/muldatamodel/inc/muldatawindow.h	Thu Dec 17 08:56:02 2009 +0200
@@ -0,0 +1,356 @@
+/*
+* Copyright (c) 2007-2008 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:  Data Window Implemenation
+*
+*/
+
+
+#ifndef MULDATAWINDOW_H_
+#define MULDATAWINDOW_H_
+
+#include "mulmodeldef.h"
+
+namespace Alf
+	{
+	
+//Forward Declaration
+class MulModelImpl;
+
+/**
+ * Implametation of Data Window Class
+ * This class maintain offset for buffer item that are required by widget,
+ * so only that much item remain present in alf model instance.It update buffer items
+ * when highlight changed and notify model to update alf model if items are not present
+ * in Alf model.
+ * 
+ */
+class MulDataWindow
+	{
+public: //Constructor and Destructor
+	
+	/**
+	 * C++ constructor
+	 * 
+	 * @param aMulModel refrece of model implementation
+	 */
+	MulDataWindow( MulModelImpl& aMulModel );
+
+	/**
+	 * Descturctor
+	 */
+	~MulDataWindow();
+	
+public: //New Method
+
+	/**
+	 * Set window size
+	 * 
+	 * @param aWindowSize No of items that are visible on screen
+	 */
+	void SetWindowSize( int aWindowSize );
+	
+	/**
+	 * Set Buffer size
+	 * Here buffser size mean number of items that will be above and below window
+	 * By default buffer size is equal to window size if following api is not called.
+	 *
+	 * @param aBufferSize Size of buffer
+	 */
+	void SetBufferSize( int aBufferSize );
+	
+	/**
+	 * Change highlighted index. 
+	 * Changing highlight will check that data window needs to be updated or not 
+	 * and if required it update data window
+	 *
+	 * @aHighlightIndex New highlighted item in Data window
+	 * @throws invaid_argument exception
+	 */
+	void SetHighlight( int aHighlightIndex );
+	
+	/**
+	 * Scroll Window to mention item index 
+	 * it will check that data window needs to be updated or not 
+	 * and if required it update data window
+	 *
+	 * @aItemIndex item index
+	 * @throws invaid_argument exception
+	 */
+	void ScrollWindow( int aItemIndex );
+	
+	/**
+	 * Return Highlighted item's index
+	 * 
+	 * @return Highlighted item's index
+	 */
+	int Highlight() const
+		{
+		return mHighlight;
+		}
+	
+	/**
+	 * Return previous top offset
+	 * 
+	 * @return Previos top offset
+	 */
+	int OldTopOffset() const
+		{
+		return mOldBufferTop;
+		}
+	
+	/**
+	 * Return previous bottom offset
+	 * 
+	 * @return Previos bottom offset
+	 */
+	int OldBottomOffset() const
+		{
+		return mOldBufferBottom;
+		}
+	
+	/**
+	 * Return current top offset
+	 * 
+	 * @return Current top offset
+	 */
+	int TopOffset() const
+		{
+		return mBufferTop;
+		}
+	
+	/**
+	 * Return current bottom offset
+	 * 
+	 * @return Current bottom offset
+	 */
+	int BottomOffset() const
+		{
+		return mBufferBottom;
+		}
+	
+	/**
+	 * Return visible window top offset
+	 * 
+	 * @return Current window top offset
+	 */
+	int TopWindowOffset() const
+		{
+		return mWindowTop;
+		}
+	
+	/**
+	 * Return visible window bottom offset
+	 * 
+	 *  @return Current window bottom offset
+	 */
+	int BottomWindowOffset() const
+		{
+		return mWindowBottom;
+		}
+		
+	/**
+	 * Return the Old Rear Top offset
+	 * 
+	 * @return Old Rear Top offset
+	 */
+	int OldRearTopOffset() const
+		{
+		return mOldRearBufferTop;
+		}
+	
+	/**
+	 * Return the Old Rear Bottom offset
+	 * 
+	 * @return Old Rear Bottom offset
+	 */
+	int OldRearBottomOffset() const
+		{
+		return mOldRearBufferBottom;
+		}		
+	
+	/**
+	 * Return the Rear Top offset
+	 * 
+	 * @return Rear Top offset
+	 */
+	int RearTopOffset() const
+		{
+		return mRearBufferTop;
+		}
+	
+	/**
+	 * Return the Rear Bottom offset
+	 * 
+	 * @return Rear Bottom offset
+	 */
+	int RearBottomOffset() const
+		{
+		return mRearBufferBottom;
+		}
+	
+	/**
+	 * Return buffer size
+	 * 
+	 * @return Current buffer size
+	 */
+	int BufferSize() const
+		{
+		return mBufferSize;
+		}
+		
+	/**
+	 * Return window size
+	 * 
+	 * @return Current window size
+	 */
+	int WindowSize() const
+		{
+		return mWindowSize;
+		}		
+	
+	/**
+	 * Check that items falls in data window or not
+	 * 
+	 * @param aItemIndex index of item
+	 * @return true if item is in data window otherwise false
+	 */
+	bool IsItemInDataWindow(int aItemIndex ) const;
+	
+	/**
+	 * Returns Relative index in datawindow from Absolute index
+	 *
+	 * @param aAbsoluteIndex Absolute index
+	 * @return Relative index
+	 */
+	int RelativeIndex( int aAbsoluteIndex ) const;
+	
+	/**
+	 * Returns Absoulte index from relative index
+	 *
+	 * @param aRelativeIndex Relative index
+	 * @return Absolute index
+	 */
+	int AbsoluteIndex( int aRelativeIndex ) const;
+	
+	/**
+	 * Check that valid window size it set or not.
+	 * 
+	 * @return true - valid window size is set 
+	 * 		   false - otherwisze
+	 */
+	bool IsWindowEnabled() const
+		{
+		return ( mWindowSize != KNotInitialized );
+		}
+
+	/**
+	 * Adjust buffer offset according to window offset
+	 */
+	void AdjustBuffer();
+	
+	/**
+	 * modify the window top and window bottom values
+	 */	
+	void SetVisibleWindow(int aWindowTop, int aWindowBottom);
+	
+	/**
+	 * Return the complete buffer size, i.e. both top, bottom buffer and the window
+	 */	
+	int ActualBufferSize() const
+		{
+		return (2 * mBufferSize) + mWindowSize;	
+		}
+		
+	/**
+	 * Change highlighted index. 
+	 * This change will not check that data window needs to be updated or not 
+	 *
+	 * @aHighlightIndex New highlighted item in Data window
+	 * @throws invaid_argument exception
+	 */
+	void UpdateHighlight( int aHighlightIndex );
+		
+	/**
+	 * Save old values
+	 */
+	void SaveOldValues()
+		{
+		mOldBufferTop = mBufferTop;
+		mOldBufferBottom = mBufferBottom;
+		
+		mOldRearBufferTop = mRearBufferTop;
+		mOldRearBufferBottom = mRearBufferBottom;
+		}
+		
+	/**
+	 * Compares the current and old buffer values and returns true if teh values are cahnged
+	 */
+	bool IsBufferOffsetChanged();					
+
+private://New Method
+	
+	/**
+	 * Check that visible window need to be updated or not.
+	 * If required it update visible window.
+	 */
+	void UpdateDataWindow();
+	
+	/**
+	 * Data window is updated and window need to sifted down
+	 */
+	void ShiftWindowDown();
+	
+	/**
+	 * Data window is updated and window need to sifted up
+	 */
+	void ShiftWindowUp();
+			
+private: // Data
+
+	MulModelImpl& mMulModel; //not own
+	
+	int mHighlight;	
+	
+	//this is index of item wich decide window offset
+	int mItemIndex; //dont know what should be better name
+	int mOldItemIndex;
+	
+	int mBufferSize;
+	
+	int mWindowSize;
+	int mWindowOffset;
+	
+	int mWindowTop;
+	int mWindowBottom;
+	
+	int mBufferTop;
+	int mBufferBottom;
+	
+	int mOldBufferTop;
+	int mOldBufferBottom;
+		
+	int mRearBufferTop;
+	int mRearBufferBottom;
+	
+	int mOldRearBufferTop;
+	int mOldRearBufferBottom;
+	
+	};
+
+	} //namespace Alf
+
+#endif /*MULDATAWINDOW_H_*/
+
+//End of file
+