Qt 5.6 | Qt Widgets | Graphics View Flow Layout Example | flowlayout.h Example File

Qt 5.6.2 Reference Documentation

# flowlayout.h Example File

graphicsview/flowlayout/flowlayout.h

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      #include <QGraphicsLayout>

      class FlowLayout : public QGraphicsLayout
      {
      public:
          FlowLayout();
          inline void addItem(QGraphicsLayoutItem *item);
          void insertItem(int index, QGraphicsLayoutItem *item);
          void setSpacing(Qt::Orientations o, qreal spacing);
          qreal spacing(Qt::Orientation o) const;

          // inherited functions
          void setGeometry(const QRectF &geom) Q_DECL_OVERRIDE;

          int count() const Q_DECL_OVERRIDE;
          QGraphicsLayoutItem *itemAt(int index) const Q_DECL_OVERRIDE;
          void removeAt(int index) Q_DECL_OVERRIDE;

      protected:
          QSizeF sizeHint(Qt::SizeHint which, const QSizeF &constraint = QSizeF()) const Q_DECL_OVERRIDE;

      private:
          qreal doLayout(const QRectF &geom, bool applyNewGeometry) const;
          QSizeF minSize(const QSizeF &constraint) const;
          QSizeF prefSize() const;
          QSizeF maxSize() const;

          QList<QGraphicsLayoutItem*> m_items;
          qreal m_spacing[2];
      };

      inline void FlowLayout::addItem(QGraphicsLayoutItem *item)
      {
          insertItem(-1, item);
      }