Qt Reference Documentation

# layoutitem.cpp Example File

graphicsview/basicgraphicslayouts/layoutitem.cpp

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     #include "layoutitem.h"

     LayoutItem::LayoutItem(QGraphicsItem *parent/* = 0*/)
         : QGraphicsLayoutItem(), QGraphicsItem(parent)
     {
         m_pix = new QPixmap(QLatin1String(":/images/block.png"));
         setGraphicsItem(this);
     }

     LayoutItem::~LayoutItem()
     {
         delete m_pix;
     }

     void LayoutItem::paint(QPainter *painter,
         const QStyleOptionGraphicsItem *option, QWidget *widget /*= 0*/)
     {
         Q_UNUSED(widget);
         Q_UNUSED(option);

         QRectF frame(QPointF(0,0), geometry().size());
         qreal w = m_pix->width();
         qreal h = m_pix->height();
         QGradientStops stops;

         // paint a background rect (with gradient)
         QLinearGradient gradient(frame.topLeft(), frame.topLeft() + QPointF(200,200));
         stops << QGradientStop(0.0, QColor(60, 60,  60));
         stops << QGradientStop(frame.height()/2/frame.height(), QColor(102, 176, 54));

         //stops << QGradientStop(((frame.height() + h)/2 )/frame.height(), QColor(157, 195,  55));
         stops << QGradientStop(1.0, QColor(215, 215, 215));
         gradient.setStops(stops);
         painter->setBrush(QBrush(gradient));
         painter->drawRoundedRect(frame, 10.0, 10.0);

         // paint a rect around the pixmap (with gradient)
         QPointF pixpos = frame.center() - (QPointF(w, h)/2);
         QRectF innerFrame(pixpos, QSizeF(w, h));
         innerFrame.adjust(-4, -4, +4, +4);
         gradient.setStart(innerFrame.topLeft());
         gradient.setFinalStop(innerFrame.bottomRight());
         stops.clear();
         stops << QGradientStop(0.0, QColor(215, 255, 200));
         stops << QGradientStop(0.5, QColor(102, 176, 54));
         stops << QGradientStop(1.0, QColor(0, 0,  0));
         gradient.setStops(stops);
         painter->setBrush(QBrush(gradient));
         painter->drawRoundedRect(innerFrame, 10.0, 10.0);
         painter->drawPixmap(pixpos, *m_pix);
     }

     QRectF LayoutItem::boundingRect() const
     {
         return QRectF(QPointF(0,0), geometry().size());
     }

     void LayoutItem::setGeometry(const QRectF &geom)
     {
         prepareGeometryChange();
         QGraphicsLayoutItem::setGeometry(geom);
         setPos(geom.topLeft());
     }

     QSizeF LayoutItem::sizeHint(Qt::SizeHint which, const QSizeF &constraint) const
     {
         switch (which) {
         case Qt::MinimumSize:
         case Qt::PreferredSize:
             // Do not allow a size smaller than the pixmap with two frames around it.
             return m_pix->size() + QSize(12, 12);
         case Qt::MaximumSize:
             return QSizeF(1000,1000);
         default:
             break;
         }
         return constraint;
     }