1 /*

     2 * Copyright (c) 2009 Nokia Corporation and/or its subsidiary(-ies).

     3 * All rights reserved.

     4 * This component and the accompanying materials are made available

     5 * under the terms of "Eclipse Public License v1.0"

     6 * which accompanies this distribution, and is available

     7 * at the URL "http://www.eclipse.org/legal/epl-v10.html".

     8 *

     9 * Initial Contributors:

    10 * Nokia Corporation - initial contribution.

    11 *

    12 * Contributors:

    13 *

    14 * Description:  Drag touch gesture recognizer.

    15 *

    16 */

    17 

    18 #ifndef C_AKNTOUCHGESTUREFWDRAGRECOGNIZER_H

    19 #define C_AKNTOUCHGESTUREFWDRAGRECOGNIZER_H

    20 

    21 

    22 #include "akntouchgesturefwbaserecognizer.h"

    23 

    24 namespace AknTouchGestureFw {

    25 

    26 /**

    27  *  Drag touch gesture recognizer.

    28  *

    29  *  @lib akntouchgesturefw

    30  *  @since S60 v5.2

    31  */

    32 NONSHARABLE_CLASS( CAknTouchGestureFwDragRecognizer )

    33     : public CAknTouchGestureFwBaseRecognizer

    34     {

    35 

    36 public:

    37 

    38     /**

    39      * Two-phased constructor.

    40      *

    41      * @param  aEngine  The gesture recognition engine.

    42      */

    43     static CAknTouchGestureFwDragRecognizer* NewL(

    44             CAknTouchGestureFwRecognitionEngine& aEngine );

    45 

    46     /**

    47      * Two-phased constructor.

    48      *

    49      * @param  aEngine  The gesture recognition engine.

    50      */

    51     static CAknTouchGestureFwDragRecognizer* NewLC(

    52             CAknTouchGestureFwRecognitionEngine& aEngine );

    53 

    54     /**

    55      * Destructor.

    56      */

    57     virtual ~CAknTouchGestureFwDragRecognizer();

    58 

    59 public: // From base class CAknTouchGestureFwBaseRecognizer.

    60 

    61     /**

    62      * Returns the recognizer's gesture group.

    63      *

    64      * @return Gesture group.

    65      */

    66     TAknTouchGestureFwGroup GestureGroup() const;

    67 

    68     /**

    69      * Cancels gesture recognition.

    70      */

    71     void CancelRecognizing();

    72 

    73     /**

    74      * Handles single pointer event.

    75      *

    76      * @param  aPointerData  Pointer event related data.

    77      */

    78     void HandleSinglePointerEventL( const TPointerEventData& aPointerData );

    79 

    80     /**

    81      * Handles multi pointer event.

    82      *

    83      * @param  aPointerData            Pointer event related data.

    84      * @param  aFirstPointerPosition   First pointer position.

    85      * @param  aSecondPointerPosition  Second pointer position.

    86      */

    87     void HandleMultiPointerEventL( const TPointerEventData& aPointerData,

    88                                    const TPoint& aFirstPointerPosition,

    89                                    const TPoint& aSecondPointerPosition );

    90 

    91 private:

    92 

    93     /**

    94      * C++ constructor.

    95      *

    96      * @param  aEngine  The gesture recognition engine.

    97      */

    98     CAknTouchGestureFwDragRecognizer(

    99             CAknTouchGestureFwRecognitionEngine& aEngine );

   100 

   101     /**

   102      * Starts single-touch recognition.

   103      *

   104      * @param  aPointerPos  Current pointer position.

   105      */

   106     void StartSingleRecognizing( const TPoint& aPointerPos );

   107 

   108     /**

   109      * Handles single-touch recognition cycle.

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

   111      *

   112      * @param  aPointerPos  New position of pointer.

   113      */

   114     void SingleRecognizeL( const TPoint& aPointerPos );

   115 

   116     /**

   117      * Completes single-touch recognition.

   118      */

   119     void CompleteSingleRecognizingL();

   120 

   121     /**

   122      * Asks engine to send drag event to observer.

   123      *

   124      * @param  aGestureState  Drag gesture state.

   125      */

   126     void SendDragEventL( TAknTouchGestureFwState aGestureState );

   127 

   128     /**

   129      * Resets the recognizer.

   130      */

   131     void Reset();

   132 

   133     /**

   134      * Returns current gesture position.

   135      *

   136      * @return Current gesture position.

   137      */

   138     TPoint CurrentPos() const;

   139 

   140     /**

   141      * Returns previous gesture position.

   142      *

   143      * @return Previous gesture position.

   144      */

   145     TPoint PreviousPos() const;

   146 

   147 private: // data

   148 

   149     /**

   150      * Start position of gesture.

   151      */

   152     TPoint iStartPosition;

   153 

   154     /**

   155      * Current position of gesture.

   156      */

   157     TPoint iCurrentPosition;

   158 

   159     /**

   160      * Previous position of gesture.

   161      */

   162     TPoint iPreviousPosition;

   163 

   164     /**

   165      * ETrue if drag gesture already detected.

   166      */

   167     TBool iDragDetected;

   168 

   169     /**

   170      * Drag threshold area.

   171      */

   172     TThresholdArea iDragArea;

   173     

   174     /**

   175      * Boolean flag to indicate if drag recognition

   176      * should be started upon single touch drag.

   177      * This flag may be set when multi touch changes to

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

   179      */

   180     TBool iStartOnSingleTouchDrag;

   181     

   182     /**

   183      * ETrue if continuous feedback ongoing.

   184      */

   185     TBool iContinuousFeedback;

   186     };

   187 

   188 } // namespace AknTouchGestureFw

   189 

   190 #endif // C_AKNTOUCHGESTUREFWDRAGRECOGNIZER_H