--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/akntouchgesturefw/inc/akntouchgesturefwdragtracer.h	Tue Feb 02 01:00:49 2010 +0200
@@ -0,0 +1,140 @@
+/*
+* Copyright (c) 2009 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: Class for tracing the direction in which pointer
+*              is being dragged.
+*
+*/
+
+#ifndef C_AKNTOUCHGESTUREFWDRAGTRACER_H
+#define C_AKNTOUCHGESTUREFWDRAGTRACER_H
+
+#include <e32base.h>
+
+namespace AknTouchGestureFw
+{
+
+/**
+ * Traces the direction in which pointer is being dragged.
+ */
+NONSHARABLE_CLASS( CAknTouchGestureFwDragTracer ) : public CBase
+    {
+public:
+
+    /**
+     * Values used to represent horizontal and vertical direction.
+     */
+    enum TDirection
+        {
+        EDirectionNone,     ///< No change in position.
+        EDirectionForward,  ///< Movement towards right or down.
+        EDirectionBackward  ///< Movement towards left or up.
+        };
+
+    /**
+     * Two-phased constructor.
+     */
+    static CAknTouchGestureFwDragTracer* NewL();
+
+    /**
+     * Two-phased constructor.
+     */
+    static CAknTouchGestureFwDragTracer* NewLC();
+
+    /**
+     * Destructor.
+     */
+    virtual ~CAknTouchGestureFwDragTracer();
+
+    /**
+     * Initializes tracer.
+     *
+     * @param  aStartPosition  Start coordinate.
+     */
+    void Initialize( const TPoint& aStartPosition );
+
+    /**
+     * Checks if dragging direction has changed with new position.
+     *
+     * @param  aPosition     New position.
+     * @param  aSensitivity  Tells how many points can be dragged to reversed
+     *                       direction before direction is changed.
+     *
+     * @return @c ETrue if direction has changed
+     */
+    TBool IsDirectionChanged( const TPoint& aPosition, TInt aSensitivity );
+
+private:
+
+    /**
+     * C++ constructor.
+     */
+    CAknTouchGestureFwDragTracer();
+
+    /**
+     * Checks if dragging direction has changed horizontally or vertically
+     * with new position. Only horizontal or vertical direction can be checked
+     * with single call.
+     *
+     * @param  aCurrentCoordinate  Current X- or Y-coordinate
+     * @param  aPrevCoordinate     Previous X- or Y-coordinate
+     * @param  aDirection          Current direction, will be updated within
+     *                             this call.
+     * @param  aCounter            Counter of coordinates that are dragged
+     *                             to reversed direction, will be updated
+     *                             within this call.
+     * @param  aSensitivity        Tells how many points can be dragged to
+     *                             reversed direction before direction is
+     *                             changed.
+     *
+     * @return @c ETrue if direction has changed
+     */
+    TBool IsDirectionChanged( TInt aCurrentCoordinate,
+                              TInt aPrevCoordinate,
+                              TDirection& aDirection,
+                              TInt& aCounter,
+                              TInt aSensitivity );
+
+private: // data
+
+    /**
+     * Current horizontal direction
+     */
+    TDirection iHorizDirection;
+
+    /**
+     * Current vertical direction
+     */
+    TDirection iVertDirection;
+
+    /**
+     * Counter for points which are to reversed horizontal direction
+     * compared to current direction.
+     */
+    TInt iHorizCounter;
+
+    /**
+     * Counter for points which are to reversed vertical direction
+     * compared to current direction.
+     */
+    TInt iVertCounter;
+
+    /**
+     * Current position.
+     */
+    TPoint iPosition;
+    };
+
+} // namespace AknTouchGestureFw
+
+#endif // C_AKNTOUCHGESTUREFWDRAGTRACER_H