Qt Documentation

Contents

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 Functions

QGraphicsLineItem(QGraphicsItem *parent = Q_NULLPTR)
QGraphicsLineItem(const QLineF &line, QGraphicsItem *parent = Q_NULLPTR)
QGraphicsLineItem(qreal x1, qreal y1, qreal x2, qreal y2, QGraphicsItem *parent = Q_NULLPTR)
~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
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

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 Function Documentation

QGraphicsLineItem::QGraphicsLineItem(QGraphicsItem *parent = Q_NULLPTR)

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

See also QGraphicsScene::addItem().

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

QGraphicsLineItem::~QGraphicsLineItem()

Destroys the QGraphicsLineItem.

[virtual] QRectF QGraphicsLineItem::boundingRect() const

Reimplemented from QGraphicsItem::boundingRect().

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

Reimplemented from QGraphicsItem::contains().

[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().

[virtual] QPainterPath QGraphicsLineItem::opaqueArea() const

Reimplemented from QGraphicsItem::opaqueArea().

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

[virtual] QPainterPath QGraphicsLineItem::shape() const

Reimplemented from QGraphicsItem::shape().

[virtual] int QGraphicsLineItem::type() const

Reimplemented from QGraphicsItem::type().

© 2017 The Qt Company Ltd. Documentation contributions included herein are the copyrights of their respective owners. The documentation provided herein is licensed under the terms of the GNU Free Documentation License version 1.3 as published by the Free Software Foundation. Qt and respective logos are trademarks of The Qt Company Ltd. in Finland and/or other countries worldwide. All other trademarks are property of their respective owners.