Qt 5.9 | Qt Widgets | C++ Classes | QGraphicsPolygonItem

Qt 5.9.9 Reference Documentation

# QGraphicsPolygonItem Class

The QGraphicsPolygonItem class provides a polygon item that you can add to a QGraphicsScene. More...

Header: | #include <QGraphicsPolygonItem>
qmake: | QT += widgets
Since: | Qt 4.2
Inherits: | QAbstractGraphicsShapeItem

- List of all members, including inherited members

## Public Functions

| QGraphicsPolygonItem(QGraphicsItem *parent = Q_NULLPTR)
| QGraphicsPolygonItem(const QPolygonF &polygon, QGraphicsItem *parent = Q_NULLPTR)
| ~QGraphicsPolygonItem()
Qt::FillRule | fillRule() const
QPolygonF | polygon() const
void | setFillRule(Qt::FillRule rule)
void | setPolygon(const QPolygonF &polygon)

## Reimplemented Public Functions

virtual QRectF | boundingRect() const
virtual bool | contains(const QPointF &point) const
virtual bool | isObscuredBy(const QGraphicsItem *item) const
virtual QPainterPath | opaqueArea() const
virtual void | paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget = Q_NULLPTR)
virtual QPainterPath | shape() const
virtual int | type() const

- 6 public functions inherited from QAbstractGraphicsShapeItem
- 176 public functions inherited from QGraphicsItem

### Additional Inherited Members

- 2 static public members inherited from QGraphicsItem
- 24 protected functions inherited from QGraphicsItem

## Detailed Description

The QGraphicsPolygonItem class provides a polygon item that you can add to a QGraphicsScene.

To set the item's polygon, pass a QPolygonF to QGraphicsPolygonItem's constructor, or call the setPolygon() function. The polygon() function returns the current polygon.

QGraphicsPolygonItem uses the polygon and the pen width to provide a reasonable implementation of boundingRect(), shape(), and contains(). The paint() function draws the polygon using the item's associated pen and brush, which you can set by calling the setPen() and setBrush() functions.

See also QGraphicsPathItem, QGraphicsRectItem, QGraphicsEllipseItem, QGraphicsTextItem, QGraphicsLineItem, QGraphicsPixmapItem, and Graphics View Framework.

## Member Function Documentation

### QGraphicsPolygonItem::QGraphicsPolygonItem(QGraphicsItem *parent = Q_NULLPTR)

Constructs a QGraphicsPolygonItem. parent is passed to QAbstractGraphicsShapeItem's constructor.

See also QGraphicsScene::addItem().

### QGraphicsPolygonItem::QGraphicsPolygonItem(const QPolygonF &polygon, QGraphicsItem *parent = Q_NULLPTR)

Constructs a QGraphicsPolygonItem with polygon as the default polygon. parent is passed to QAbstractGraphicsShapeItem's constructor.

See also QGraphicsScene::addItem().

### QGraphicsPolygonItem::~QGraphicsPolygonItem()

Destroys the QGraphicsPolygonItem.

### `[virtual]` QRectF QGraphicsPolygonItem::boundingRect() const

Reimplemented from QGraphicsItem::boundingRect().

### `[virtual]` bool QGraphicsPolygonItem::contains(const QPointF &point) const

Reimplemented from QGraphicsItem::contains().

### Qt::FillRule QGraphicsPolygonItem::fillRule() const

Returns the fill rule of the polygon. The default fill rule is Qt::OddEvenFill.

See also setFillRule(), QPainterPath::fillRule(), and QPainter::drawPolygon().

### `[virtual]` bool QGraphicsPolygonItem::isObscuredBy(const QGraphicsItem *item) const

Reimplemented from QGraphicsItem::isObscuredBy().

### `[virtual]` QPainterPath QGraphicsPolygonItem::opaqueArea() const

Reimplemented from QGraphicsItem::opaqueArea().

### `[virtual]` void QGraphicsPolygonItem::paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget = Q_NULLPTR)

Reimplemented from QGraphicsItem::paint().

### QPolygonF QGraphicsPolygonItem::polygon() const

Returns the item's polygon, or an empty polygon if no polygon has been set.

See also setPolygon().

### void QGraphicsPolygonItem::setFillRule(Qt::FillRule rule)

Sets the fill rule of the polygon to rule. The default fill rule is Qt::OddEvenFill.

See also fillRule(), QPainterPath::fillRule(), and QPainter::drawPolygon().

### void QGraphicsPolygonItem::setPolygon(const QPolygonF &polygon)

Sets the item's polygon to be the given polygon.

See also polygon().

### `[virtual]` QPainterPath QGraphicsPolygonItem::shape() const

Reimplemented from QGraphicsItem::shape().

### `[virtual]` int QGraphicsPolygonItem::type() const

Reimplemented from QGraphicsItem::type().