1 /*

     2 * Copyright (c) 2007 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:  Gesture helper implementation

    15 *

    16 */

    17 

    18 

    19 #ifndef _XNGESTUREHELPER_H_

    20 #define _XNGESTUREHELPER_H_

    21 

    22 // System includes

    23 #include <e32base.h>

    24 

    25 // User includes

    26 #include "xngesturerecogniser.h"

    27 

    28 // Forward declarations

    29 class CXnNode;

    30 struct TPointerEvent;

    31 

    32 /**

    33  * XnGestureHelper namespace

    34  * Used for the whole gesture family - Gesture recognizer, gesture helper, 

    35  * Point array

    36  */

    37 namespace XnGestureHelper

    38     {

    39     

    40     // Forward declarations

    41     class CHoldingTimer;

    42     class CXnGesture;

    43     

    44     // Constants

    45     const TInt KGestureMinSpeed = 25;

    46     const TInt KGestureMinLength = 100;

    47         

    48     /**

    49      *  Implementation of CGestureHelper interface

    50      *

    51      *  @ingroup group_xnlayoutengine

    52      */

    53     NONSHARABLE_CLASS( CXnGestureHelper ) : public CBase

    54         {

    55     

    56         /** private implementation class */

    57         friend class CHoldingTimer;

    58     

    59     public:

    60         

    61         /** 2-phase constructor */

    62         static CXnGestureHelper* NewL( CXnNode& aNode );

    63 

    64         /** Destructor */

    65         ~CXnGestureHelper();

    66 

    67         /** 

    68          * See GestureHelper, SetHoldingEnabled function

    69          * 

    70          * @see CGestureHelper::SetHoldingEnabled 

    71          */

    72         void SetHoldingEnabled( TBool aEnabled );

    73         

    74         /** 

    75          * See Gesturehelper, IsHoldingEnabled function

    76          * 

    77          * @see CGestureHelper::IsHoldingEnabled 

    78          */

    79         TBool IsHoldingEnabled() const;

    80 

    81         /** 

    82          * Gets the owner

    83          * 

    84          * @return Owner

    85          */                

    86         CXnNode* Owner() const;

    87         

    88         /** 

    89          * Sets destination

    90          * 

    91          * @aParam Destination

    92          */        

    93         void SetDestination( CXnNode* aDestination );

    94 

    95         /** 

    96          * Gets destination

    97          * 

    98          * @return Destination

    99          */                         

   100         CXnNode* Destination() const;

   101         

   102         /** 

   103          * See GestureHelper Handlepointervent

   104          * 

   105          * @see CGestureHelper::HandlePointerEventL 

   106          */ 

   107         TXnGestureCode HandlePointerEventL( const TPointerEvent& aEvent ); 

   108                     

   109         /** Reset helper state */

   110         void Reset();

   111 

   112     private:

   113         

   114         /** Constructor */

   115         CXnGestureHelper( CXnNode& aNode );

   116 

   117         /** 

   118          * Returns if the helper is processing

   119          *         

   120          * @return ETrue if the helper has not started processing a gesture

   121          */

   122         inline TBool IsIdle() const; 

   123         

   124         /** 

   125          * Add a point to the sequence of points that make up the gesture 

   126          */

   127         inline void AddPointL( const TPointerEvent& aEvent );

   128         

   129         /** 

   130          * Add a point to the sequence of points that make up the gesture

   131          * 

   132          * @return                    

   133          */

   134         inline TInt AddPoint( const TPointerEvent& aEvent );

   135         

   136         /** 

   137          * Activates holding and notifies observer that holding has been 

   138          * started 

   139          */

   140         void StartHoldingL();

   141         

   142         /** 

   143          * Check if swipe if between defined values 

   144          * 

   145          * @return Swiping left/right/none 

   146          */

   147         TXnGestureCode ValidSwipe() const;

   148 

   149     private:

   150 

   151         /** 

   152          * Gesture owner, Not owned.

   153          */        

   154         CXnNode& iOwner;        

   155         

   156         /** 

   157          * Gesture is the logical representation of a sequence of points 

   158          * arriving at certain times

   159          */ 

   160         CXnGesture* iGesture;

   161 

   162         /** 

   163          * holding is activated when user keeps pointer down in the same place 

   164          * for a longer period. the holding timer activates off when enough 

   165          * time has passed.

   166          */

   167         CHoldingTimer* iHoldingTimer;

   168 

   169         /** 

   170          * Gesture destination, Not owned.

   171          */        

   172         CXnNode* iDestination;

   173         

   174         TXnGestureCode iDirection;

   175         };

   176     } // GestureHelper

   177 

   178 #endif // _XNGESTUREHELPER_H_