/*

* 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:   AknTreeListView physics handler

*

*/

#ifndef C_AKNSTYLUSPOPUPMENUPHYSICSHANDLER_H

#define C_AKNSTYLUSPOPUPMENUPHYSICSHANDLER_H

#include <e32base.h>

#include <w32std.h>

#include <aknphysicsobserveriface.h>

class CAknPhysics;

class CAknStylusPopUpMenuContent;

/**

 *  StylusPopUpmenu physics handler.

 *

 *  @lib aknhlist

 *  @since S60 v5.0

 */

NONSHARABLE_CLASS( CAknStylusPopUpMenuPhysicsHandler ) : public CBase,

    public MAknPhysicsObserver

    {

public:

    /**

     * Two-phased constructor.

     */

    static CAknStylusPopUpMenuPhysicsHandler* NewL( CAknStylusPopUpMenuContent* aPopUpMenuContent );

    /**

     * Two-phased constructor.

     */

    static CAknStylusPopUpMenuPhysicsHandler* NewLC( CAknStylusPopUpMenuContent* aPopUpMenuContent );

    /**

     * Destructor.

     */

    virtual ~CAknStylusPopUpMenuPhysicsHandler();

public:

    /**

     * Handles the pointer event received by AknStylusPopUpMenuContent

     *

     * @param aPointerEvent Pointer event to handle.

     */

    void HandlePointerEventL( const TPointerEvent& aPointerEvent );                      

    /**

     * Sets view rect.

     *

     * @param aRect New view rect.

     */

    void SetViewRect( const TRect& aRect );

    /**

     * Sets item height.

     *

     * @param aItemHeight New item height.

     */

    void SetItemHeight( TInt aItemHeight );

    /**

     * Sets world height.

     *

     * @param aWorldHeight New world height.

     */

    void SetWorldHeight( TInt aWorldHeight );

    /**

     * Returns offset. Used to draw partial items.

     */

    TInt Offset() const;

    /**

     * Initializes physics.

     */

    void InitPhysicsL();

    /**

     * Scrolls the view to new position.

     *

     * @param aNewScrollIndex New view position.

     */

    void HandleScrollEvent( TInt aNewScrollIndex );

    /**

     * Resets physics so that location is set to world's top position.

     * 

     * @since S60 5.2

     */

    void Reset();

public: // From base class MAknPhysicsObserver.

    /**

     * Called when view position changes.

     *

     * @param  aNewPosition  The new position of the view.

     * @param  aDrawNow      @c ETrue if the screen is to be redrawn,

     *                       otherwise @c EFalse.

     * @param  aFlags        Additional flags, not used currently.

     */

    virtual void ViewPositionChanged( const TPoint& aNewPosition,

                                      TBool aDrawNow = ETrue,

                                      TUint aFlags = 0 );

    /**

     * Called when emulation has ended.

     */

    virtual void PhysicEmulationEnded();

    /**

     * Returns the observer's view position.

     *

     * @return Physics observer's view position.

     */

    virtual TPoint ViewPosition() const;

private:

    /**

     * C++ constructor.

     */

    CAknStylusPopUpMenuPhysicsHandler( CAknStylusPopUpMenuContent* aPopUpMenuContent );

    /**

     * Symbian second-phase constructor.

     */

    void ConstructL();

    /**

     * Returns drag threshold.

     *

     * @return drag threshold.

     */

    TInt DragThreshold();

    /**

     * Sets highlight to item.

     * 

     * @param aItem Item to be highlighted.

     */

    void SetHighlight( TInt aItem );

    /**

     * Moves view to correct position.

     * 

     * @param  aDrawNow  Whether or not the view is drawn. If @c EFalse,

     *                   then only the logical state is updated.

     */

    void ScrollView( TBool aDrawNow = ETrue );

    /**

     * Stops physics.

     */

    void StopPhysics();

private: // data

    /**

     * PopUpMenuContent

     * Not own.

     */

    CAknStylusPopUpMenuContent* iPopUpMenuContent;

    /**

     * Scroll index.

     */

    TInt iScrollIndex;

    /**

     * Height of one item.

     */

    TInt iItemHeight;

    /**

     * Height of world.

     */

    TInt iWorldHeight;

    /**

     * Current pointer position.

     */   

    TPoint iPosition;

    /**

     * Start (pointer down) position.

     */

    TPoint iStartPosition;

    /**

     * View rect.

     */

    TRect iViewRect;

    /**

     *  ETrue if pointer down event received but pointer up not.

     */

    TBool iPressedDown;

    /**

     * ETrue if panning functionality is activated.

     */

    TBool iPanningActivated;

    /**

     * Pointer down start time.

     */

    TTime iStartTime;

    /**

     * Physics. 

     * Own.

     */

    CAknPhysics *iPhysics;

    /**

     * Physics handler flags.

     */

    TBitFlags iFlags;

    /**

     * Previous offset.

     */

    TInt iPrevOffset;

    /**

     * Previous topmost item

     */

    TInt iPrevTopmostItem;

    /**

     * count of offset item

     */

    TInt iOffsetItemCount;

    };

#endif // C_AKNSTYLUSPOPUPMENUPHYSICSHANDLER_H