main.cpp Example File

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 #include <QGraphicsWidget>
 #include <QGraphicsProxyWidget>
 #include <QGraphicsAnchorLayout>
 #include <QtWidgets>

 static QGraphicsProxyWidget *createItem(const QSizeF &minimum = QSizeF(100.0, 100.0),
                                    const QSizeF &preferred = QSize(150.0, 100.0),
                                    const QSizeF &maximum = QSizeF(200.0, 100.0),
                                    const QString &name = "0")
 {
     QGraphicsProxyWidget *w = new QGraphicsProxyWidget;
     w->setWidget(new QPushButton(name));
     w->setData(0, name);
     w->setMinimumSize(minimum);
     w->setPreferredSize(preferred);
     w->setMaximumSize(maximum);

     w->setSizePolicy(QSizePolicy::Preferred, QSizePolicy::Preferred);
     return w;
 }

 int main(int argc, char **argv)
 {
     QApplication app(argc, argv);

     QGraphicsScene scene;
     scene.setSceneRect(0, 0, 800, 480);

     QSizeF minSize(30, 100);
     QSizeF prefSize(210, 100);
     QSizeF maxSize(300, 100);

     QGraphicsProxyWidget *a = createItem(minSize, prefSize, maxSize, "A");
     QGraphicsProxyWidget *b = createItem(minSize, prefSize, maxSize, "B");
     QGraphicsProxyWidget *c = createItem(minSize, prefSize, maxSize, "C");
     QGraphicsProxyWidget *d = createItem(minSize, prefSize, maxSize, "D");
     QGraphicsProxyWidget *e = createItem(minSize, prefSize, maxSize, "E");
     QGraphicsProxyWidget *f = createItem(QSizeF(30, 50), QSizeF(150, 50), maxSize, "F (overflow)");
     QGraphicsProxyWidget *g = createItem(QSizeF(30, 50), QSizeF(30, 100), maxSize, "G (overflow)");

     QGraphicsAnchorLayout *l = new QGraphicsAnchorLayout;
     l->setSpacing(0);

     QGraphicsWidget *w = new QGraphicsWidget(0, Qt::Window);
     w->setPos(20, 20);
     w->setLayout(l);

     // vertical
     l->addAnchor(a, Qt::AnchorTop, l, Qt::AnchorTop);
     l->addAnchor(b, Qt::AnchorTop, l, Qt::AnchorTop);

     l->addAnchor(c, Qt::AnchorTop, a, Qt::AnchorBottom);
     l->addAnchor(c, Qt::AnchorTop, b, Qt::AnchorBottom);
     l->addAnchor(c, Qt::AnchorBottom, d, Qt::AnchorTop);
     l->addAnchor(c, Qt::AnchorBottom, e, Qt::AnchorTop);

     l->addAnchor(d, Qt::AnchorBottom, l, Qt::AnchorBottom);
     l->addAnchor(e, Qt::AnchorBottom, l, Qt::AnchorBottom);

     l->addAnchor(c, Qt::AnchorTop, f, Qt::AnchorTop);
     l->addAnchor(c, Qt::AnchorVerticalCenter, f, Qt::AnchorBottom);
     l->addAnchor(f, Qt::AnchorBottom, g, Qt::AnchorTop);
     l->addAnchor(c, Qt::AnchorBottom, g, Qt::AnchorBottom);

     // horizontal
     l->addAnchor(l, Qt::AnchorLeft, a, Qt::AnchorLeft);
     l->addAnchor(l, Qt::AnchorLeft, d, Qt::AnchorLeft);
     l->addAnchor(a, Qt::AnchorRight, b, Qt::AnchorLeft);

     l->addAnchor(a, Qt::AnchorRight, c, Qt::AnchorLeft);
     l->addAnchor(c, Qt::AnchorRight, e, Qt::AnchorLeft);

     l->addAnchor(b, Qt::AnchorRight, l, Qt::AnchorRight);
     l->addAnchor(e, Qt::AnchorRight, l, Qt::AnchorRight);
     l->addAnchor(d, Qt::AnchorRight, e, Qt::AnchorLeft);

     l->addAnchor(l, Qt::AnchorLeft, f, Qt::AnchorLeft);
     l->addAnchor(l, Qt::AnchorLeft, g, Qt::AnchorLeft);
     l->addAnchor(f, Qt::AnchorRight, g, Qt::AnchorRight);

     scene.addItem(w);
     scene.setBackgroundBrush(Qt::darkGreen);
     QGraphicsView view(&scene);

     view.show();

     return app.exec();
 }