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// Copyright (C) 2012 Thorbjørn Lund Martsum - tmartsum[at]gmail.com
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only WITH Qt-GPL-exception-1.0
#include <QtWidgets>
class MyGraphicsItem : public QGraphicsRectItem
{
public:
MyGraphicsItem() : QGraphicsRectItem()
{
setFlags(QGraphicsItem::ItemIsSelectable);
}
void paint(QPainter *painter, const QStyleOptionGraphicsItem * /* option*/, QWidget * /*widget*/) override
{
if (isSelected())
painter->fillRect(rect(), QColor(255, 0, 0));
else
painter->fillRect(rect(), QColor(0, 255, 0));
}
};
class MyGraphicsView : public QGraphicsView
{
Q_OBJECT
public:
MyGraphicsView(QWidget *w, QLabel *l) : QGraphicsView(w), rubberbandLabel(l)
{
setDragMode(QGraphicsView::RubberBandDrag);
connect(this, SIGNAL(rubberBandChanged(QRect, QPointF, QPointF)), this, SLOT(updateRubberbandInfo(QRect, QPointF, QPointF)));
}
protected:
void mouseMoveEvent(QMouseEvent *event) override
{
QGraphicsView::mouseMoveEvent(event);
int rightmostInView = viewport()->mapToGlobal(viewport()->geometry().topRight()).x();
int xglobal = event->globalX();
if (xglobal > rightmostInView)
horizontalScrollBar()->setValue(horizontalScrollBar()->value() + 10);
int bottomPos = viewport()->mapToGlobal(viewport()->geometry().bottomRight()).y();
int yglobal = event->globalY();
if (yglobal > bottomPos)
verticalScrollBar()->setValue(verticalScrollBar()->value() + 10);
}
protected slots:
void updateRubberbandInfo(QRect r, QPointF from, QPointF to)
{
QString textToShow;
QDebug s(&textToShow);
s << r << from << to;
rubberbandLabel->setText(textToShow);
}
protected:
QLabel *rubberbandLabel;
};
int main(int argc, char *argv[])
{
QApplication app(argc, argv);
QWidget w;
w.setLayout(new QVBoxLayout);
QLabel *l = new QLabel(&w);
MyGraphicsView *v = new MyGraphicsView(&w, l);
w.layout()->addWidget(v);
w.layout()->addWidget(l);
QGraphicsScene s(0.0, 0.0, 5000.0, 5000.0);
v->setScene(&s);
v->setInteractive(true);
v->setRubberBandSelectionMode(Qt::IntersectsItemBoundingRect);
for (int u = 0; u < 100; ++u)
for (int n = 0; n < 100; ++n) {
MyGraphicsItem *item = new MyGraphicsItem();
item->setRect(QRectF(n * 80.0, u * 80.0, 50.0, 20.0));
s.addItem(item);
}
w.show();
app.exec();
return 0;
}
#include "rubberbandtest.moc"
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