src_gui_graphicsview_qgraphicsview.cpp

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QGraphicsScene scene;
scene.addText("Hello, world!");
 
QGraphicsView view(&scene);
view.show();
 
 
QGraphicsScene scene;
scene.addRect(QRectF(-10, -10, 20, 20));
 
QGraphicsView view(&scene);
view.setRenderHints(QPainter::Antialiasing | QPainter::SmoothPixmapTransform);
view.show();
 
 
QGraphicsView view;
view.setBackgroundBrush(QImage(":/images/backgroundtile.png"));
view.setCacheMode(QGraphicsView::CacheBackground);
 
 
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();
 
 
QGraphicsScene scene;
scene.addItem(...
...
 
QGraphicsView view(&scene);
view.show();
...
 
QPrinter printer(QPrinter::HighResolution);
printer.setPageSize(QPrinter::A4);
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));
 
 
 
void CustomView::mousePressEvent(QMouseEvent *event)
{
    qDebug() << "There are" << items(event->pos()).size()
             << "items at position" << mapToScene(event->pos());
}
 
 
void CustomView::mousePressEvent(QMouseEvent *event)
{
    if (QGraphicsItem *item = itemAt(event->pos())) {
        qDebug() << "You clicked on item" << item;
    } else {
        qDebug("You didn't click on an item.");
    }
}
 
 
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();