Qt 5.11 | Qt Widgets | Diagram Scene Example | arrow.h Example File

Qt 5.11.3 Reference Documentation

# arrow.h Example File

graphicsview/diagramscene/arrow.h

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      #ifndef ARROW_H
      #define ARROW_H

      #include <QGraphicsLineItem>

      #include "diagramitem.h"

      class QGraphicsPolygonItem;
      class QGraphicsLineItem;
      class QGraphicsScene;
      class QRectF;
      class QGraphicsSceneMouseEvent;
      class QPainterPath;

      class Arrow : public QGraphicsLineItem
      {
      public:
          enum { Type = UserType + 4 };

          Arrow(DiagramItem *startItem, DiagramItem *endItem,
            QGraphicsItem *parent = 0);

          int type() const override { return Type; }
          QRectF boundingRect() const override;
          QPainterPath shape() const override;
          void setColor(const QColor &color) { myColor = color; }
          DiagramItem *startItem() const { return myStartItem; }
          DiagramItem *endItem() const { return myEndItem; }

          void updatePosition();

      protected:
          void paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget = 0) override;

      private:
          DiagramItem *myStartItem;
          DiagramItem *myEndItem;
          QColor myColor;
          QPolygonF arrowHead;
      };

      #endif // ARROW_H