QGraphicsLineItem Class

The QGraphicsLineItem class provides a line item that you can add to a QGraphicsScene. More...

Header: #include <QGraphicsLineItem>
qmake: QT += widgets
Since: Qt 4.2
Inherits: QGraphicsItem

Public Types

enum anonymous { Type }

Public Functions

QGraphicsLineItem(QGraphicsItem *parent = nullptr)
QGraphicsLineItem(const QLineF &line, QGraphicsItem *parent = nullptr)
QGraphicsLineItem(qreal x1, qreal y1, qreal x2, qreal y2, QGraphicsItem *parent = nullptr)
virtual ~QGraphicsLineItem()
QLineF line() const
QPen pen() const
void setLine(const QLineF &line)
void setLine(qreal x1, qreal y1, qreal x2, qreal y2)
void setPen(const QPen &pen)

Reimplemented Public Functions

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

Additional Inherited Members

Detailed Description

The QGraphicsLineItem class provides a line item that you can add to a QGraphicsScene.

To set the item's line, pass a QLineF to QGraphicsLineItem's constructor, or call the setLine() function. The line() function returns the current line. By default the line is black with a width of 0, but you can change this by calling setPen().

QGraphicsLineItem uses the line and the pen width to provide a reasonable implementation of boundingRect(), shape(), and contains(). The paint() function draws the line using the item's associated pen.

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

Member Type Documentation

enum QGraphicsLineItem::anonymous

The value returned by the virtual type() function.

Constant Value Description
QGraphicsLineItem::Type 6 A graphics line item

Member Function Documentation

QGraphicsLineItem::QGraphicsLineItem(QGraphicsItem *parent = nullptr)

Constructs a QGraphicsLineItem. parent is passed to QGraphicsItem's constructor.

See also QGraphicsScene::addItem().

QGraphicsLineItem::QGraphicsLineItem(const QLineF &line, QGraphicsItem *parent = nullptr)

Constructs a QGraphicsLineItem, using line as the default line. parent is passed to QGraphicsItem's constructor.

See also QGraphicsScene::addItem().

QGraphicsLineItem::QGraphicsLineItem(qreal x1, qreal y1, qreal x2, qreal y2, QGraphicsItem *parent = nullptr)

Constructs a QGraphicsLineItem, using the line between (x1, y1) and (x2, y2) as the default line. parent is passed to QGraphicsItem's constructor.

See also QGraphicsScene::addItem().

[virtual] QGraphicsLineItem::~QGraphicsLineItem()

Destroys the QGraphicsLineItem.

[override virtual] QRectF QGraphicsLineItem::boundingRect() const

Reimplemented from QGraphicsItem::boundingRect().

[override virtual] bool QGraphicsLineItem::contains(const QPointF &point) const

Reimplemented from QGraphicsItem::contains().

[override virtual] bool QGraphicsLineItem::isObscuredBy(const QGraphicsItem *item) const

Reimplemented from QGraphicsItem::isObscuredBy().

QLineF QGraphicsLineItem::line() const

Returns the item's line, or a null line if no line has been set.

See also setLine().

[override virtual] QPainterPath QGraphicsLineItem::opaqueArea() const

Reimplemented from QGraphicsItem::opaqueArea().

[override virtual] void QGraphicsLineItem::paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget = nullptr)

Reimplemented from QGraphicsItem::paint().

QPen QGraphicsLineItem::pen() const

Returns the item's pen, or a black solid 0-width pen if no pen has been set.

See also setPen().

void QGraphicsLineItem::setLine(const QLineF &line)

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

See also line().

void QGraphicsLineItem::setLine(qreal x1, qreal y1, qreal x2, qreal y2)

This is an overloaded function.

Sets the item's line to be the line between (x1, y1) and (x2, y2).

This is the same as calling setLine(QLineF(x1, y1, x2, y2)).

void QGraphicsLineItem::setPen(const QPen &pen)

Sets the item's pen to pen. If no pen is set, the line will be painted using a black solid 0-width pen.

See also pen().

[override virtual] QPainterPath QGraphicsLineItem::shape() const

Reimplemented from QGraphicsItem::shape().

[override virtual] int QGraphicsLineItem::type() const

Reimplemented from QGraphicsItem::type().

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