/*

* Copyright (c) 2002-2006 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:  View switcher.

*

*/

#ifndef _XNVIEWSWITCHER_H

#define _XNVIEWSWITCHER_H

//  System includes

#include <e32base.h>

#include <akntouchgesturefw.h>

// User includes

#include "xnviewmanager.h"

class CXnViewControlAdapter;

using namespace AknTouchGestureFw;

// Class declaration

/**

 * This class handles view swithing when "finger follow" feature is used. 

 * The windows of current, next and previous views are moved along with the finger. 

 * Final view switch animation has been handled here as well.

 * 

*  @ingroup group_xnlayoutengine

*  @lib xn3layoutengine.lib

*  @since S60 5.2

*/   

NONSHARABLE_CLASS( CXnViewSwitcher ) : public CBase

   {

    /**

     * Important information of a view to be dragged.

     */

    struct TViewInformation

        {

        CXnControlAdapter*  iAdapter;

        CXnViewData*        iViewData;

        TBool               iReadyToDraw;

        TBool               iBgDrawn;

        };

    /**

     * States for the view swithcing using "finger follow".

     */

    enum TViewSwitchState

        {

        KViewSwitchIdle,

        KViewSwitchBegin,

        KViewSwitchDragOngoing,

        KViewSwitchScroll

        };

public:

    // Constructors and destructor

    /**

     * 2 phase construction.

     */

    static CXnViewSwitcher* NewL();

    /**

     * Destructor.

     */

    ~CXnViewSwitcher();

    /**

     * Is finger follow feature activated

     */

    TBool FingerFollowSupported() const;

    /**

     * Try to handle and consume pointer event

     */

    TBool ProcessPointerEventL( const TPointerEvent& aPointerEvent );

    /**

     * Check if flick or some gesture occured during drag

     */            

    void TouchGesture( TAknTouchGestureFwType& aTouchGesture );

    /**

     * Updates the client rect

     */            

    void SizeChanged( TRect aRect );

private: // constructors

    /**

     * C++ default constructor

     */    

    CXnViewSwitcher();

    /**

     * 2nd phase constructor

     */

    void ConstructL();

    /**

     * View scroll timer callback

     */    

    static TInt TimerCallback( TAny *aPtr );

    /**

     * Gets value of finger follow support from AI repository

     */    

    TBool IsFingerFollowSupportedL() const;

    /**

     * Adjusts current view position. Used in final animation.

     */    

    void Scroll();

    /**

     * Moves windows according to the current view position.

     */    

    void DoScroll();

    /**

     * Start view dragging by setting up view control adapters

     */    

    TBool SetupViewsL();

    /**

     * Layouts and renders the given view out of sight. 

     */    

    void PrepareViewL( CXnViewSwitcher::TViewInformation& aView );

    /**

     * Removes focused node and sends the up event in order to prevent activate triggers and long tapping.

     */

    void StartViewDraggingL();

    /**

     * Stop view dragging and start view scroll

     */    

    void StartViewScrolling();

    /**

     * View scrolling ended. 

     */    

    void ViewSwitchEndedL();

    /**

     * Get view data

     */    

    CXnViewData* ViewData( CXnViewData& aCurrentViewData, TInt aView );

    /**

     * Clear view information of current, next and previous views.

     */    

    void ClearViews();

    /**

     * Sets whether next, current or previous view is to be activeted. 

     * Updated also background if needed.

     */    

    void UpdateViewToBeActivated( TInt aOffset );

    /**

     * Changes background image and runs NGA effect. 

     */    

    void ChangeBackground( CXnViewData& aCurrent, CXnViewData& aNext );

private: // data

    /** 

     * AppUi 

     */

    CXnAppUiAdapter& iAppUi;

    /** 

     * Client rect set by UI Engine 

     */

    TRect iRect;

    /** 

     * Whether the feature is supported or not. ETrue when finger follow is supported 

     */

    TBool iFingerFollowSupported;

    /**

     * Timer for animating view switch.

     * Own.  

     */    

    CPeriodic* iTimer;

    /** 

     * Important information of the current view. 

     */

    TViewInformation iCurrentView;

    /** 

     * Important information of the view coming from the right side. 

     */

    TViewInformation iNextView;    

    /** 

     * Important information of the view coming from the left side. 

     */

    TViewInformation iPreviousView;

    /**

     * Flick gesture type. 

     */

    //TAknTouchGestureFwType iTouchGesture;

    /**

     * The state of view switch. 

     */

    TViewSwitchState iViewSwitchState;

    /**

     * Scroll speed in pixels. 

     */

    TInt iScrollSpeed;

    /**

     * Total scroll distance from the beginning in mode KViewSwitchDragOngoing.

     * Remaining distance to be scrolled in mode KViewSwitchScroll. 

     */

    TInt iScrollDistance;

    /**

     * Measures the scroll distance in current direction. I.e. if direction changes, 

     * this is set to 0. 

     */

    TInt iScrollDirectionDistance;

    /**

     * Position of the current view in the beginning. 

     */

    TPoint iViewStartPosition;

    /**

     * Position in the beginning. 

     */

    TPoint iStartPosition;

    /**

     * Current view position from the beginning. 

     */

    TPoint iViewPosition;

    /**

     * View to be activated. 

     */

    TInt iActivateView;

    /**

     * Tick amount to be used when calculating drag speed. 

     */    

    TInt iTickAmount;

    /**

     * Scroll direction. 

     */    

    TInt iDirection;

   };

#endif      // _XNVIEWSWITCHER_H

// End of File