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:   glxzoomwidget.h

    15 *               definition of the class glxzoomwidget which controls the Zoom behavior of coverflow.

    16 *

    17 */

    18 #ifndef GLXZOOMWIDGET_H

    19 #define GLXZOOMWIDGET_H

    20 

    21 #include <QObject>

    22 #include <QGraphicsWidget>

    23 #include <QPixmap>

    24 #include <hbscrollarea.h>

    25 

    26 class QGestureEvent;

    27 class QPinchGesture;

    28 class HbIconItem;

    29 class GlxImageDecoderWrapper;

    30 

    31 const int MAXZVALUE = 100;

    32 const int MINZVALUE = 0;

    33 

    34 class GlxZoomWidget : public HbScrollArea

    35 {

    36     Q_OBJECT

    37 

    38     public:

    39     GlxZoomWidget (QGraphicsItem *parent = NULL);

    40     ~GlxZoomWidget ();

    41     void setModel (QAbstractItemModel *model) ;

    42     void indexChanged(int index);

    43     void setWindowSize(QSize windowSize);

    44     void cleanUp();

    45     void activate();

    46 

    47     signals:

    48     void pinchGestureReceived(int index);

    49     void zoomWidgetMovedBackground(int index);

    50 

    51     public slots:

    52     //for Decoder support

    53     void decodedImageAvailable();

    54 

    55     protected:

    56     bool sceneEvent(QEvent *event);

    57     bool sceneEventFilter(QGraphicsItem *watched,QEvent *event);

    58     protected slots:

    59     void dataChanged(QModelIndex startIndex, QModelIndex endIndex);

    60     void sendDecodeRequest(int index);

    61 

    62     private:

    63     bool executeGestureEvent(QGraphicsItem *source,QGestureEvent *event);

    64     //Responsible for changing the transforms of the widget wrt the ZF and center

    65 	//Also adjusts the ZF, center and final size so as to respect the boundaries

    66     void zoomImage(qreal zoomFactor, QPointF center);

    67     //This API will adjust the gesture center to maintain boundaries

    68 	//called from GlxZoomWidget::zoomImage

    69     void adjustGestureCenter(QPointF & gestureCenter, qreal& zoomFactor);

    70     //this API will limit the max/min Zoom Size possible

    71 	//called from GlxZoomWidget::zoomImage

    72     void limitRequiredSize(QSizeF &requiredSize);

    73 	//gets the latest focussed image from the model

    74     void retreiveFocusedImage();

    75     //finalize the transform and update the sizehint of mZoomWidget

    76     void finalizeWidgetTransform();

    77     //get the focused image from the model

    78     QPixmap getFocusedImage();

    79 

    80     //data members

    81     private:

    82     //view widgets

    83     QGraphicsPixmapItem *mZoomItem;   //Item containing the pixmap

    84     QGraphicsWidget *mZoomWidget;     //container :all scaling and transforms would be done on this widget

    85     HbIconItem* mBlackBackgroundItem; //for setting black background

    86 

    87     //to be in sync with the model

    88     QAbstractItemModel *mModel;

    89     int mFocusIndex;

    90 

    91     //size parameter

    92     QSizeF mItemSize;        // the actual pixmap size. Keep it updated with latest pixmap size

    93     QSizeF mStepCurrentSize; //to save the size before gesture started

    94     QSizeF mCurrentSize;     //save sizes scaled by gesture

    95     QSize mWindowSize;      //the window size

    96     QSizeF mMinScaleSize;   //minimum posible size

    97     QSizeF mMinDecScaleSize;   //the Minimum scale limit after which the image scaling down should be decelerated

    98     QSizeF mMaxScaleSize;   // the maximum scale limit

    99     QSizeF mMaxScaleDecSize;   // the Maximum scale limit after which the image scaling should be decelerated

   100 

   101     //for Decoder support

   102     GlxImageDecoderWrapper* mImageDecoder;

   103 

   104     //status flags

   105 	//To check if the decode request has already been send or not

   106     bool mImageDecodeRequestSend; 

   107 	//To check if the pinch gesture is in progress to block any events to HbScrollArea

   108     bool mPinchGestureOngoing; 

   109     //to check if decoded image is available

   110     bool mDecodedImageAvailable;

   111 

   112 };

   113 #endif  //GLXZOOMWIDGET_H