1 /*

     2 * Copyright (c) 2010 Nokia Corporation and/or its subsidiary(-ies).

     3 * All rights reserved.

     4 *

     5 * This program is free software: you can redistribute it and/or modify

     6 * it under the terms of the GNU Lesser General Public License as published by

     7 * the Free Software Foundation, version 2.1 of the License.

     8 *

     9 * This program is distributed in the hope that it will be useful,

    10 * but WITHOUT ANY WARRANTY; without even the implied warranty of

    11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

    12 * GNU Lesser General Public License for more details.

    13 *

    14 * You should have received a copy of the GNU Lesser General Public License

    15 * along with this program.  If not,

    16 * see "http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html/".

    17 *

    18 * Description:

    19 *

    20 */

    21 

    22 #include "ScrollableViewBase.h"

    23 

    24 

    25 #include "Kinetics/KineticScroller.h"

    26 

    27 #include <QGraphicsScene>

    28 #include <QGraphicsSceneMouseEvent>

    29 #include <QPointF>

    30 

    31 namespace GVA {

    32 

    33 ScrollableViewBase::ScrollableViewBase(QGraphicsItem* parent, Qt::WindowFlags wFlags)

    34     : QGraphicsWidget(parent, wFlags)

    35     , m_scrollWidget(0)

    36 {

    37     //To get only the mouse events within the ScrollableViewBase.

    38     setFlag(QGraphicsItem::ItemClipsToShape, true);

    39 

    40     //To disable childrens painting outside the ViewportItem's rect.

    41     setFlag(QGraphicsItem::ItemClipsChildrenToShape, true);

    42 

    43     //To speed up painting.

    44     setFlag(QGraphicsItem::ItemHasNoContents, true);

    45     setAttribute(Qt::WA_OpaquePaintEvent, true);

    46 

    47     m_kineticScroller = new KineticScroller(this);

    48 

    49     //Event filter on all children of the viewport, so that all mouse

    50     //events can be intercepted and used for kinetic scrolling.

    51     setFiltersChildEvents(true);

    52 }

    53 

    54 ScrollableViewBase::~ScrollableViewBase()

    55 {}

    56 

    57 void ScrollableViewBase::setWidget(QGraphicsWidget* view)

    58 {

    59     if (view == m_scrollWidget)

    60         return;

    61 

    62     if (m_scrollWidget) {

    63         m_scrollWidget->setParentItem(0);

    64         delete m_scrollWidget;

    65     }

    66 

    67     m_scrollWidget = view;

    68     m_scrollWidget->setAttribute(Qt::WA_OpaquePaintEvent, true);

    69     m_scrollWidget->setParentItem(this);

    70 }

    71 

    72 QSize ScrollableViewBase::viewportSize() const

    73 {

    74     return size().toSize();

    75 }

    76 

    77 QPoint ScrollableViewBase::maximumScrollPosition() const

    78 {

    79     QSizeF contentsSize = m_scrollWidget->size();

    80     QSizeF viewportSize = size();

    81     QSize maxScrollSize = (contentsSize - viewportSize).toSize();

    82 

    83     return QPoint(qMax(0, maxScrollSize.width()), qMax(0, maxScrollSize.height()));

    84 }

    85 

    86 QPoint ScrollableViewBase::scrollPosition() const

    87 {

    88     return (-scrollWidgetPos()).toPoint();

    89 }

    90 

    91 void ScrollableViewBase::setScrollPosition(const QPoint& pos, const QPoint& overShoot)

    92 {

    93     m_overShoot = overShoot;

    94     setScrollWidgetPos(-pos);

    95 }

    96 

    97 void ScrollableViewBase::stateChanged(KineticScrollable::State oldState

    98                                       , KineticScrollable::State newState)

    99 {

   100     Q_UNUSED(oldState);

   101     Q_UNUSED(newState);

   102 }

   103 

   104 void ScrollableViewBase::setScrollWidgetGeometry(const QRectF& geom)

   105 {

   106     scrollWidget()->setGeometry(adjustScrollWidgetRect(geom));

   107 }

   108 

   109 QRectF ScrollableViewBase::adjustScrollWidgetRect(const QRectF& rect)

   110 {

   111     //FIX ME : Stop animation of scroll widget before adjusting it here??

   112     QRectF newRect(rect);

   113 

   114     QSizeF widgetSize = rect.size();

   115     QSizeF viewportSize = size();

   116 

   117     qreal w = viewportSize.width() - widgetSize.width();

   118     qreal h = viewportSize.height() - widgetSize.height();

   119 

   120     if ( w > 0 ) {

   121         newRect.moveLeft(0);

   122         m_extraPos.setX(w/2);

   123       }

   124     else {

   125     	m_extraPos.setX(0);

   126         if (newRect.x() < w)

   127             newRect.moveLeft(w);

   128         if (newRect.x() > 0)

   129             newRect.moveLeft(0);

   130     }

   131 

   132     if ( h > 0 ) {

   133         m_extraPos.setY(h/2);

   134         newRect.moveTop(0);

   135       }

   136     else {

   137     	 m_extraPos.setY(0);

   138         if (newRect.y() < h)

   139             newRect.moveTop(h);

   140         if (newRect.y() > 0)

   141             newRect.moveTop(0);

   142     }

   143     //newRect.translate(m_extraPos);

   144     newRect.translate(m_overShoot);

   145     return newRect;

   146 }

   147 

   148 void ScrollableViewBase::setScrollWidgetPos(const QPointF& pos)

   149 {

   150     setScrollWidgetGeometry(QRectF(pos, scrollWidget()->size()));

   151 }

   152 

   153 QPointF ScrollableViewBase::scrollWidgetPos() const

   154 {

   155     return scrollWidget()->pos()  /*- m_extraPos*/ - m_overShoot;

   156 }

   157 

   158 } //namespace GVA