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    41 

    42 #include <QGraphicsSceneResizeEvent>

    43 #include <QGraphicsWidget>

    44 #include <QDebug>

    45 #include "abstractscrollarea.h"

    46 #include "scrollbar.h"

    47 

    48 AbstractScrollArea::AbstractScrollArea(QGraphicsWidget *parent)

    49     : GvbWidget(parent)

    50     , m_viewport(0)

    51     , m_horizontalScrollBar(0)

    52     , m_verticalScrollBar(0)

    53     , m_prevHorizontalValue(0.0)

    54     , m_prevVerticalValue(0.0)

    55 {

    56     setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);

    57     setContentsMargins(0, 0, 0, 0);     

    58 

    59     m_horizontalScrollBar = new ScrollBar(Qt::Horizontal, this);

    60     m_horizontalScrollBar->hide();

    61     m_horizontalScrollBar->setContentsMargins(0, 0, 0, 0); 

    62     m_horizontalScrollBarPolicy = Qt::ScrollBarAsNeeded;

    63     m_horizontalScrollBar->setZValue(zValue()+1); // Raise scroll bar to top

    64     m_horizontalScrollBar->setVisible(false);

    65 

    66     connect(m_horizontalScrollBar, SIGNAL(sliderPositionChange(qreal)),

    67             this, SLOT(horizontalScroll(qreal)));

    68     connect(m_horizontalScrollBar, SIGNAL(sliderPressed()),

    69             this, SLOT(horizontalScrollStart()));

    70 

    71     m_verticalScrollBar = new ScrollBar(Qt::Vertical, this);

    72     m_verticalScrollBar->hide();

    73     m_verticalScrollBar->setContentsMargins(0, 0, 0, 0); 

    74     m_verticalScrollBarPolicy = Qt::ScrollBarAsNeeded;

    75     m_verticalScrollBar->setZValue(zValue()+1); // Raise scroll bar to top

    76     m_verticalScrollBar->setVisible(false);

    77 

    78     connect(m_verticalScrollBar, SIGNAL(sliderPositionChange(qreal)),

    79             this, SLOT(verticalScroll(qreal)));

    80     connect(m_verticalScrollBar, SIGNAL(sliderPressed()),

    81             this, SLOT(verticalScrollStart()));

    82 

    83     QGraphicsWidget *viewport = new QGraphicsWidget;

    84     setViewport(viewport);

    85 }

    86 

    87 AbstractScrollArea::~AbstractScrollArea()

    88 {

    89 }

    90 

    91 ScrollBar *AbstractScrollArea::verticalScrollBar() const

    92 {

    93     return m_verticalScrollBar;

    94 }

    95 

    96 ScrollBar *AbstractScrollArea::horizontalScrollBar() const

    97 {

    98     return m_horizontalScrollBar;

    99 }

   100 

   101 void AbstractScrollArea::setHorizontalScrollBarPolicy(Qt::ScrollBarPolicy policy)

   102 {

   103     m_horizontalScrollBarPolicy = policy;

   104 }

   105 

   106 void AbstractScrollArea::setVerticalScrollBarPolicy(Qt::ScrollBarPolicy policy)

   107 {

   108     m_verticalScrollBarPolicy = policy;

   109 }

   110 

   111 Qt::ScrollBarPolicy AbstractScrollArea::verticalScrollBarPolicy() const

   112 {

   113     return m_verticalScrollBarPolicy;

   114 }

   115 

   116 Qt::ScrollBarPolicy AbstractScrollArea::horizontalScrollBarPolicy() const

   117 {

   118     return m_horizontalScrollBarPolicy;

   119 }

   120 

   121 QGraphicsWidget *AbstractScrollArea::viewport() const

   122 {

   123     return m_viewport;

   124 }

   125 

   126 void AbstractScrollArea::setViewport(QGraphicsWidget *viewport)

   127 {

   128     if (m_viewport) {

   129         m_viewport->setParentItem(0);

   130 

   131         QList<QGraphicsItem*> children = m_viewport->childItems();

   132 

   133         foreach (QGraphicsItem *child, children)

   134             child->setParentItem(0);

   135 

   136         delete m_viewport;

   137     }

   138 

   139     m_viewport = viewport;

   140 

   141     if (viewport) {

   142 

   143         m_viewport->setParentItem(this);

   144         m_viewport->setContentsMargins(0, 0, 0, 0);

   145 

   146         adjustScrollBars();

   147     }

   148 

   149     emit viewportChanged(viewport);

   150 }

   151 

   152 bool AbstractScrollArea::event(QEvent *e)

   153 {

   154     if (e->type() == QEvent::ApplicationLayoutDirectionChange

   155        || e->type() == QEvent::LayoutDirectionChange) {

   156     } else if (e->type() == QEvent::GraphicsSceneResize) {        

   157         QGraphicsSceneResizeEvent *event = 

   158             static_cast<QGraphicsSceneResizeEvent*>(e);

   159 

   160         QSizeF newSize = event->newSize();

   161         QRectF hrect = m_horizontalScrollBar->boundingRect();

   162         QRectF vrect = m_verticalScrollBar->boundingRect();

   163 

   164         QSizeF vpSize = newSize;

   165 

   166         if (m_horizontalScrollBarPolicy != Qt::ScrollBarAlwaysOff)

   167             vpSize.setHeight(newSize.height() - hrect.height());

   168         if (m_verticalScrollBarPolicy != Qt::ScrollBarAlwaysOff)

   169             vpSize.setWidth(newSize.width() - vrect.width());

   170 

   171         m_viewport->resize(vpSize);

   172 

   173         adjustScrollBars();

   174     }

   175 

   176     return QGraphicsWidget::event(e);

   177 }

   178 

   179 

   180 void AbstractScrollArea::scrollContentsBy(qreal dx, qreal dy)

   181 {

   182     Q_UNUSED(dx)

   183     Q_UNUSED(dy)

   184     prepareGeometryChange();

   185 }

   186 

   187 void AbstractScrollArea::verticalScrollStart()

   188 {

   189     m_prevVerticalValue = m_verticalScrollBar->sliderPosition(); 

   190 }

   191 

   192 void AbstractScrollArea::verticalScroll(qreal value)

   193 {

   194     qreal dy = value - m_prevVerticalValue;

   195     if (!qFuzzyCompare(dy,qreal(0.0))) {

   196         scrollContentsBy(0.0, dy);

   197         m_prevVerticalValue = value;

   198     }

   199 }

   200 

   201 void AbstractScrollArea::horizontalScrollStart()

   202 {

   203     m_prevHorizontalValue = m_horizontalScrollBar->sliderPosition(); 

   204 }

   205 

   206 void AbstractScrollArea::horizontalScroll(qreal value)

   207 {

   208     qreal dx = value - m_prevHorizontalValue;

   209     if (!qFuzzyCompare(dx,qreal(0.0))) {

   210         scrollContentsBy(dx, 0.0);

   211         m_prevHorizontalValue = value;

   212     }

   213 }

   214 

   215 void AbstractScrollArea::adjustScrollBars()

   216 {

   217     if (m_horizontalScrollBarPolicy == Qt::ScrollBarAlwaysOff) {

   218         m_horizontalScrollBar->hide();

   219     } else {

   220         m_horizontalScrollBar->show();

   221 

   222         QRectF sbgeom = boundingRect();

   223 

   224         sbgeom.setTop(sbgeom.bottom() - m_horizontalScrollBar->boundingRect().height());

   225         sbgeom.setRight(sbgeom.right() - m_verticalScrollBar->boundingRect().width());

   226         m_horizontalScrollBar->setGeometry(sbgeom);

   227     }

   228 

   229     if (m_verticalScrollBarPolicy == Qt::ScrollBarAlwaysOff) {

   230         m_verticalScrollBar->hide();

   231         QRectF sbgeom = boundingRect();

   232         sbgeom.setLeft(sbgeom.right());

   233         sbgeom.setBottom(sbgeom.bottom());

   234         m_verticalScrollBar->setGeometry(sbgeom);

   235     } else {

   236         m_verticalScrollBar->show();

   237 

   238         QRectF sbgeom = boundingRect();

   239 

   240         sbgeom.setLeft(sbgeom.right() - m_verticalScrollBar->boundingRect().width());

   241         if (m_horizontalScrollBarPolicy != Qt::ScrollBarAlwaysOff)

   242             sbgeom.setBottom(sbgeom.bottom() - m_horizontalScrollBar->boundingRect().height());

   243         m_verticalScrollBar->setGeometry(sbgeom);

   244     }

   245 }

   246 

   247 

   248 

   249