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50
51#include <QGraphicsLayout>
52
53class FlowLayout : public QGraphicsLayout
54{
55public:
56 FlowLayout(QGraphicsLayoutItem *parent = nullptr);
57 inline void addItem(QGraphicsLayoutItem *item);
58 void insertItem(int index, QGraphicsLayoutItem *item);
59 void setSpacing(Qt::Orientations o, qreal spacing);
60 qreal spacing(Qt::Orientation o) const;
61
62 // inherited functions
63 void setGeometry(const QRectF &geom) override;
64
65 int count() const override;
66 QGraphicsLayoutItem *itemAt(int index) const override;
67 void removeAt(int index) override;
68
69protected:
70 QSizeF sizeHint(Qt::SizeHint which, const QSizeF &constraint = QSizeF()) const override;
71
72private:
73 qreal doLayout(const QRectF &geom, bool applyNewGeometry) const;
74 QSizeF minSize(const QSizeF &constraint) const;
75 QSizeF prefSize() const;
76 QSizeF maxSize() const;
77
78 QVector<QGraphicsLayoutItem*> m_items;
79 qreal m_spacing[2] = {6, 6};
80};
81
82
83inline void FlowLayout::addItem(QGraphicsLayoutItem *item)
84{
85 insertItem(index: -1, item);
86}
87

source code of qtbase/examples/widgets/graphicsview/flowlayout/flowlayout.h