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50
51#include "layoutitem.h"
52
53#include <QGradient>
54#include <QPainter>
55
56//! [0]
57LayoutItem::LayoutItem(QGraphicsItem *parent)
58 : QGraphicsLayoutItem(), QGraphicsItem(parent),
59 m_pix(QPixmap(QLatin1String(":/images/block.png")))
60{
61 setGraphicsItem(this);
62}
63//! [0]
64
65//! [1]
66void LayoutItem::paint(QPainter *painter, const QStyleOptionGraphicsItem *option,
67 QWidget *widget)
68{
69 Q_UNUSED(widget);
70 Q_UNUSED(option);
71
72 QRectF frame(QPointF(0, 0), geometry().size());
73 const QSize pmSize = m_pix.size();
74 QGradientStops stops;
75//! [1]
76
77//! [2]
78 // paint a background rect (with gradient)
79 QLinearGradient gradient(frame.topLeft(), frame.topLeft() + QPointF(200,200));
80 stops << QGradientStop(0.0, QColor(60, 60, 60));
81 stops << QGradientStop(frame.height() / 2 / frame.height(), QColor(102, 176, 54));
82
83 //stops << QGradientStop(((frame.height() + h)/2 )/frame.height(), QColor(157, 195, 55));
84 stops << QGradientStop(1.0, QColor(215, 215, 215));
85 gradient.setStops(stops);
86 painter->setBrush(QBrush(gradient));
87 painter->drawRoundedRect(frame, 10.0, 10.0);
88
89 // paint a rect around the pixmap (with gradient)
90 QPointF pixpos = frame.center() - (QPointF(pmSize.width(), pmSize.height()) / 2);
91 QRectF innerFrame(pixpos, pmSize);
92 innerFrame.adjust(-4, -4, 4, 4);
93 gradient.setStart(innerFrame.topLeft());
94 gradient.setFinalStop(innerFrame.bottomRight());
95 stops.clear();
96 stops << QGradientStop(0.0, QColor(215, 255, 200));
97 stops << QGradientStop(0.5, QColor(102, 176, 54));
98 stops << QGradientStop(1.0, QColor(0, 0, 0));
99 gradient.setStops(stops);
100 painter->setBrush(QBrush(gradient));
101 painter->drawRoundedRect(innerFrame, 10.0, 10.0);
102 painter->drawPixmap(pixpos, m_pix);
103}
104//! [2]
105
106//! [3]
107QRectF LayoutItem::boundingRect() const
108{
109 return QRectF(QPointF(0, 0), geometry().size());
110}
111//! [3]
112
113//! [4]
114void LayoutItem::setGeometry(const QRectF &geom)
115{
116 prepareGeometryChange();
117 QGraphicsLayoutItem::setGeometry(geom);
118 setPos(geom.topLeft());
119}
120//! [4]
121
122//! [5]
123QSizeF LayoutItem::sizeHint(Qt::SizeHint which, const QSizeF &constraint) const
124{
125 switch (which) {
126 case Qt::MinimumSize:
127 case Qt::PreferredSize:
128 // Do not allow a size smaller than the pixmap with two frames around it.
129 return m_pix.size() + QSize(12, 12);
130 case Qt::MaximumSize:
131 return QSizeF(1000,1000);
132 default:
133 break;
134 }
135 return constraint;
136}
137//! [5]
138

source code of qtbase/examples/widgets/graphicsview/basicgraphicslayouts/layoutitem.cpp