/*

* 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:  Drag touch gesture recognizer.

*

*/

#ifndef C_AKNTOUCHGESTUREFWDRAGRECOGNIZER_H

#define C_AKNTOUCHGESTUREFWDRAGRECOGNIZER_H

#include "akntouchgesturefwbaserecognizer.h"

namespace AknTouchGestureFw {

/**

 *  Drag touch gesture recognizer.

 *

 *  @lib akntouchgesturefw

 *  @since S60 v5.2

 */

NONSHARABLE_CLASS( CAknTouchGestureFwDragRecognizer )

    : public CAknTouchGestureFwBaseRecognizer

    {

public:

    /**

     * Two-phased constructor.

     *

     * @param  aEngine  The gesture recognition engine.

     */

    static CAknTouchGestureFwDragRecognizer* NewL(

            CAknTouchGestureFwRecognitionEngine& aEngine );

    /**

     * Two-phased constructor.

     *

     * @param  aEngine  The gesture recognition engine.

     */

    static CAknTouchGestureFwDragRecognizer* NewLC(

            CAknTouchGestureFwRecognitionEngine& aEngine );

    /**

     * Destructor.

     */

    virtual ~CAknTouchGestureFwDragRecognizer();

public: // From base class CAknTouchGestureFwBaseRecognizer.

    /**

     * Returns the recognizer's gesture group.

     *

     * @return Gesture group.

     */

    TAknTouchGestureFwGroup GestureGroup() const;

    /**

     * Cancels gesture recognition.

     */

    void CancelRecognizing();

    /**

     * Handles single pointer event.

     *

     * @param  aPointerData  Pointer event related data.

     */

    void HandleSinglePointerEventL( const TPointerEventData& aPointerData );

    /**

     * Handles multi pointer event.

     *

     * @param  aPointerData            Pointer event related data.

     * @param  aFirstPointerPosition   First pointer position.

     * @param  aSecondPointerPosition  Second pointer position.

     */

    void HandleMultiPointerEventL( const TPointerEventData& aPointerData,

                                   const TPoint& aFirstPointerPosition,

                                   const TPoint& aSecondPointerPosition );

private:

    /**

     * C++ constructor.

     *

     * @param  aEngine  The gesture recognition engine.

     */

    CAknTouchGestureFwDragRecognizer(

            CAknTouchGestureFwRecognitionEngine& aEngine );

    /**

     * Starts single-touch recognition.

     *

     * @param  aPointerPos  Current pointer position.

     */

    void StartSingleRecognizing( const TPoint& aPointerPos );

    /**

     * Handles single-touch recognition cycle.

     * Called for every drag event when one pointer is down.

     *

     * @param  aPointerPos  New position of pointer.

     */

    void SingleRecognizeL( const TPoint& aPointerPos );

    /**

     * Completes single-touch recognition.

     */

    void CompleteSingleRecognizingL();

    /**

     * Asks engine to send drag event to observer.

     *

     * @param  aGestureState  Drag gesture state.

     */

    void SendDragEventL( TAknTouchGestureFwState aGestureState );

    /**

     * Resets the recognizer.

     */

    void Reset();

    /**

     * Returns current gesture position.

     *

     * @return Current gesture position.

     */

    TPoint CurrentPos() const;

    /**

     * Returns previous gesture position.

     *

     * @return Previous gesture position.

     */

    TPoint PreviousPos() const;

private: // data

    /**

     * Start position of gesture.

     */

    TPoint iStartPosition;

    /**

     * Current position of gesture.

     */

    TPoint iCurrentPosition;

    /**

     * Previous position of gesture.

     */

    TPoint iPreviousPosition;

    /**

     * ETrue if drag gesture already detected.

     */

    TBool iDragDetected;

    /**

     * Drag threshold area.

     */

    TThresholdArea iDragArea;

    /**

     * Boolean flag to indicate if drag recognition

     * should be started upon single touch drag.

     * This flag may be set when multi touch changes to

     * single (i.e. another pointer was released).

     */

    TBool iStartOnSingleTouchDrag;

    /**

     * ETrue if continuous feedback ongoing.

     */

    TBool iContinuousFeedback;

    };

} // namespace AknTouchGestureFw

#endif // C_AKNTOUCHGESTUREFWDRAGRECOGNIZER_H