DISPLACE  1.0
A spatial model of fisheries to help sustainable fishing and maritime spatial planning
QCPItemAnchor Class Reference

An anchor of an item to which positions can be attached to. More...

#include <qcustomplot.h>

Inheritance diagram for QCPItemAnchor:
QCPItemPosition

Public Member Functions

 QCPItemAnchor (QCustomPlot *parentPlot, QCPAbstractItem *parentItem, const QString &name, int anchorId=-1)
 
virtual ~QCPItemAnchor ()
 
QString name () const
 
virtual QPointF pixelPosition () const
 

Protected Member Functions

virtual QCPItemPositiontoQCPItemPosition ()
 
void addChildX (QCPItemPosition *pos)
 
void removeChildX (QCPItemPosition *pos)
 
void addChildY (QCPItemPosition *pos)
 
void removeChildY (QCPItemPosition *pos)
 

Protected Attributes

QString mName
 
QCustomPlotmParentPlot
 
QCPAbstractItemmParentItem
 
int mAnchorId
 
QSet< QCPItemPosition * > mChildrenX
 
QSet< QCPItemPosition * > mChildrenY
 

Friends

class QCPItemPosition
 

Detailed Description

An anchor of an item to which positions can be attached to.

An item (QCPAbstractItem) may have one or more anchors. Unlike QCPItemPosition, an anchor doesn't control anything on its item, but provides a way to tie other items via their positions to the anchor.

For example, a QCPItemRect is defined by its positions topLeft and bottomRight. Additionally it has various anchors like top, topRight or bottomLeft etc. So you can attach the start (which is a QCPItemPosition) of a QCPItemLine to one of the anchors by calling QCPItemPosition::setParentAnchor on start, passing the wanted anchor of the QCPItemRect. This way the start of the line will now always follow the respective anchor location on the rect item.

Note that QCPItemPosition derives from QCPItemAnchor, so every position can also serve as an anchor to other positions.

To learn how to provide anchors in your own item subclasses, see the subclassing section of the QCPAbstractItem documentation.

Constructor & Destructor Documentation

◆ QCPItemAnchor()

QCPItemAnchor::QCPItemAnchor ( QCustomPlot parentPlot,
QCPAbstractItem parentItem,
const QString &  name,
int  anchorId = -1 
)

Creates a new QCPItemAnchor. You shouldn't create QCPItemAnchor instances directly, even if you want to make a new item subclass. Use QCPAbstractItem::createAnchor instead, as explained in the subclassing section of the QCPAbstractItem documentation.

◆ ~QCPItemAnchor()

QCPItemAnchor::~QCPItemAnchor ( )
virtual

Member Function Documentation

◆ addChildX()

void QCPItemAnchor::addChildX ( QCPItemPosition pos)
protected

◆ addChildY()

void QCPItemAnchor::addChildY ( QCPItemPosition pos)
protected

◆ name()

QString QCPItemAnchor::name ( ) const
inline

◆ pixelPosition()

QPointF QCPItemAnchor::pixelPosition ( ) const
virtual

Returns the final absolute pixel position of the QCPItemAnchor on the QCustomPlot surface.

The pixel information is internally retrieved via QCPAbstractItem::anchorPixelPosition of the parent item, QCPItemAnchor is just an intermediary.

Reimplemented in QCPItemPosition.

◆ removeChildX()

void QCPItemAnchor::removeChildX ( QCPItemPosition pos)
protected

◆ removeChildY()

void QCPItemAnchor::removeChildY ( QCPItemPosition pos)
protected

◆ toQCPItemPosition()

QCPItemPosition * QCPItemAnchor::toQCPItemPosition ( )
inlineprotectedvirtual

Returns 0 if this instance is merely a QCPItemAnchor, and a valid pointer of type QCPItemPosition* if it actually is a QCPItemPosition (which is a subclass of QCPItemAnchor).

This safe downcast functionality could also be achieved with a dynamic_cast. However, QCustomPlot avoids dynamic_cast to work with projects that don't have RTTI support enabled (e.g. -fno-rtti flag with gcc compiler).

Reimplemented in QCPItemPosition.

Friends And Related Function Documentation

◆ QCPItemPosition

friend class QCPItemPosition
friend

Member Data Documentation

◆ mAnchorId

int QCPItemAnchor::mAnchorId
protected

◆ mChildrenX

QSet<QCPItemPosition*> QCPItemAnchor::mChildrenX
protected

◆ mChildrenY

QSet<QCPItemPosition*> QCPItemAnchor::mChildrenY
protected

◆ mName

QString QCPItemAnchor::mName
protected

◆ mParentItem

QCPAbstractItem* QCPItemAnchor::mParentItem
protected

◆ mParentPlot

QCustomPlot* QCPItemAnchor::mParentPlot
protected

The documentation for this class was generated from the following files: