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// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
#include <QtWidgets>
#include <QPrinter>
void examples()
{
{
//! [0]
QGraphicsScene scene;
scene.addText("Hello, world!");
QGraphicsView view(&scene);
view.show();
//! [0]
}
{
//! [1]
QGraphicsScene scene;
scene.addRect(QRectF(-10, -10, 20, 20));
QGraphicsView view(&scene);
view.setRenderHints(QPainter::Antialiasing | QPainter::SmoothPixmapTransform);
view.show();
//! [1]
}
{
//! [2]
QGraphicsView view;
view.setBackgroundBrush(QImage(":/images/backgroundtile.png"));
view.setCacheMode(QGraphicsView::CacheBackground);
//! [2]
}
{
//! [4]
QGraphicsScene scene;
scene.addItem(someItem);
//...
QGraphicsView view(&scene);
view.show();
//...
QPrinter printer(QPrinter::HighResolution);
printer.setDocName("Example");
QPainter painter(&printer);
// print, fitting the viewport contents into a full page
view.render(&painter);
// print the upper half of the viewport into the lower.
// half of the page.
QRect viewport = view.viewport()->rect();
view.render(&painter,
QRectF(0, printer.height() / 2,
printer.width(), printer.height() / 2),
viewport.adjusted(0, 0, 0, -viewport.height() / 2));
//! [4]
}
{
//! [7]
QGraphicsScene scene;
scene.addText("GraphicsView rotated clockwise");
QGraphicsView view(&scene);
view.rotate(90); // the text is rendered with a 90 degree clockwise rotation
view.show();
//! [7]
}
}
class CustomView : public QGraphicsView
{
public:
void mousePressEvent(QMouseEvent *event) override;
};
//! [5_6_declaration]
void CustomView::mousePressEvent(QMouseEvent *event)
{
//! [5_6_declaration]
{
//! [5]
qDebug() << "There are" << items(event->pos()).size()
<< "items at position" << mapToScene(event->pos());
//! [5]
}
{
//! [6]
if (QGraphicsItem *item = itemAt(event->pos())) {
qDebug() << "You clicked on item" << item;
} else {
qDebug("You didn't click on an item.");
}
//! [6]
}
//! [5_6_end]
}
//! [5_6_end]