Qt 5.6 | Qt Widgets | Simple Anchor Layout Example | main.cpp Example File

Qt 5.6.2 Reference Documentation

# main.cpp Example File

graphicsview/simpleanchorlayout/main.cpp

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      ** This file is part of the examples of the Qt Toolkit.
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      #include <QtWidgets>

      class Widget : public QGraphicsWidget
      {
      public:
          Widget(const QColor &color, const QColor &textColor, const QString &caption,
                 QGraphicsItem *parent = 0)
              : QGraphicsWidget(parent)
              , caption(caption)
              , color(color)
              , textColor(textColor)
          {
          }

          void paint(QPainter *painter, const QStyleOptionGraphicsItem *, QWidget * = 0) Q_DECL_OVERRIDE
          {
              QFont font;
              font.setPixelSize(0.75 * qMin(boundingRect().width(), boundingRect().height()));

              painter->fillRect(boundingRect(), color);
              painter->save();
              painter->setFont(font);
              painter->setPen(textColor);
              painter->drawText(boundingRect(), Qt::AlignCenter, caption);
              painter->restore();
          }

      private:
          QString caption;
          QColor color;
          QColor textColor;
      };

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

          QGraphicsScene *scene = new QGraphicsScene();

          Widget *a = new Widget(Qt::blue, Qt::white, "a");
          a->setPreferredSize(100, 100);
          Widget *b = new Widget(Qt::green, Qt::black, "b");
          b->setPreferredSize(100, 100);
          Widget *c = new Widget(Qt::red, Qt::black, "c");
          c->setPreferredSize(100, 100);

          QGraphicsAnchorLayout *layout = new QGraphicsAnchorLayout();
      /*
          layout->addAnchor(a, Qt::AnchorTop, layout, Qt::AnchorTop);
          layout->addAnchor(a, Qt::AnchorLeft, layout, Qt::AnchorLeft);
      */
          layout->addCornerAnchors(a, Qt::TopLeftCorner, layout, Qt::TopLeftCorner);

          layout->addAnchor(b, Qt::AnchorLeft, a, Qt::AnchorRight);
          layout->addAnchor(b, Qt::AnchorTop, a, Qt::AnchorBottom);

          // Place a third widget below the second.
          layout->addAnchor(b, Qt::AnchorBottom, c, Qt::AnchorTop);

      /*
          layout->addAnchor(b, Qt::AnchorLeft, c, Qt::AnchorLeft);
          layout->addAnchor(b, Qt::AnchorRight, c, Qt::AnchorRight);
      */

          layout->addAnchors(b, c, Qt::Horizontal);

          // Anchor the bottom-right corner of the third widget to the bottom-right
          // corner of the layout.
          layout->addCornerAnchors(c, Qt::BottomRightCorner, layout, Qt::BottomRightCorner);

          QGraphicsWidget *w = new QGraphicsWidget(0, Qt::Window | Qt::CustomizeWindowHint | Qt::WindowTitleHint);
          w->setPos(20, 20);
          w->setMinimumSize(100, 100);
          w->setPreferredSize(320, 240);
          w->setLayout(layout);
          w->setWindowTitle(QApplication::translate("simpleanchorlayout", "QGraphicsAnchorLayout in use"));
          scene->addItem(w);

          QGraphicsView *view = new QGraphicsView();
          view->setScene(scene);
          view->setWindowTitle(QApplication::translate("simpleanchorlayout", "Simple Anchor Layout"));

          view->resize(360, 320);
          view->show();

          return app.exec();
      }