A labeling engine rule which prevents labels being placed overlapping features from a different layer. More...

#include <qgslabelingenginerule_impl.h>

Inheritance diagram for QgsLabelingEngineRuleAvoidLabelOverlapWithFeature:

Public Member Functions
	QgsLabelingEngineRuleAvoidLabelOverlapWithFeature ()

	~QgsLabelingEngineRuleAvoidLabelOverlapWithFeature () override

bool	candidateIsIllegal (const pal::LabelPosition *candidate, QgsLabelingEngineContext &context) const override
	Returns `true` if a labeling candidate violates the rule and should be eliminated.

QgsLabelingEngineRuleAvoidLabelOverlapWithFeature *	clone () const override
	Creates a clone of this rule.

QString	description () const override
	Returns a user-friendly description of the rule.

QString	displayType () const override
	Returns a user-friendly, translated string representing the rule type.

QString	id () const override
	Returns a string uniquely identifying the rule subclass.

QgsMapLayer *	labeledLayer () const
	Returns the layer providing the labels.

bool	prepare (QgsRenderContext &context) override
	Prepares the rule.

void	readXml (const QDomElement &element, const QgsReadWriteContext &context) override
	Reads the rule properties from an XML element.

void	resolveReferences (const QgsProject *project) override
	Resolves reference to layers from stored layer ID.

void	setLabeledLayer (QgsMapLayer *layer)
	Sets the layer providing the labels.

void	setTargetLayer (QgsVectorLayer *layer)
	Sets the layer providing the features which labels must not overlap.

QgsVectorLayer *	targetLayer () const
	Returns the layer providing the features which labels must not overlap.

void	writeXml (QDomDocument &doc, QDomElement &element, const QgsReadWriteContext &context) const override
	Writes the rule properties to an XML element.

Public Member Functions inherited from QgsAbstractLabelingEngineRule
virtual	~QgsAbstractLabelingEngineRule ()

bool	active () const
	Returns `true` if the rule is active.

virtual void	alterCandidateCost (pal::LabelPosition *candidate, QgsLabelingEngineContext &context) const
	Provides an opportunity for the rule to alter the cost for a candidate.

virtual bool	candidatesAreConflicting (const pal::LabelPosition lp1, const pal::LabelPosition lp2) const
	Returns `true` if a labeling candidate lp1 conflicts with lp2 after applying the rule.

virtual bool	isAvailable () const
	Returns `true` if the rule is available for use within the current QGIS environment.

virtual QgsRectangle	modifyCandidateConflictSearchBoundingBox (const QgsRectangle &candidateBounds) const
	Returns a (possibly expanded) bounding box to use when searching for conflicts for a candidate.

QString	name () const
	Returns the name for this instance of the rule.

void	setActive (bool active)
	Sets whether the rule is active.

void	setName (const QString &name)
	Sets the name for this instance of the rule.

Additional Inherited Members
Protected Member Functions inherited from QgsAbstractLabelingEngineRule
virtual void	copyCommonProperties (QgsAbstractLabelingEngineRule *other) const
	Copies common properties from this object to an other.

Detailed Description

A labeling engine rule which prevents labels being placed overlapping features from a different layer.

Since: QGIS 3.40

Definition at line 386 of file qgslabelingenginerule_impl.h.

Constructor & Destructor Documentation

◆ QgsLabelingEngineRuleAvoidLabelOverlapWithFeature()

QgsLabelingEngineRuleAvoidLabelOverlapWithFeature::QgsLabelingEngineRuleAvoidLabelOverlapWithFeature ( )

default

◆ ~QgsLabelingEngineRuleAvoidLabelOverlapWithFeature()

QgsLabelingEngineRuleAvoidLabelOverlapWithFeature::~QgsLabelingEngineRuleAvoidLabelOverlapWithFeature ( )

overridedefault

Member Function Documentation

◆ candidateIsIllegal()

bool QgsLabelingEngineRuleAvoidLabelOverlapWithFeature::candidateIsIllegal	(	const pal::LabelPosition *	candidate,
		QgsLabelingEngineContext &	context
	)		const

overridevirtual

Returns true if a labeling candidate violates the rule and should be eliminated.

The default implementation returns false.

Reimplemented from QgsAbstractLabelingEngineRule.

Definition at line 581 of file qgslabelingenginerule_impl.cpp.

◆ clone()

QgsLabelingEngineRuleAvoidLabelOverlapWithFeature * QgsLabelingEngineRuleAvoidLabelOverlapWithFeature::clone ( ) const

overridevirtual

Creates a clone of this rule.

The caller takes ownership of the returned object.

Implements QgsAbstractLabelingEngineRule.

Definition at line 497 of file qgslabelingenginerule_impl.cpp.

◆ description()

QString QgsLabelingEngineRuleAvoidLabelOverlapWithFeature::description ( ) const

overridevirtual

Returns a user-friendly description of the rule.

This should include the rule name() if set, and other useful details for users to quickly identify the rule's purpose when shown in a tooltip.

The returned string may contain HTML formatting.

Reimplemented from QgsAbstractLabelingEngineRule.

Definition at line 516 of file qgslabelingenginerule_impl.cpp.

◆ displayType()

QString QgsLabelingEngineRuleAvoidLabelOverlapWithFeature::displayType ( ) const

overridevirtual

Returns a user-friendly, translated string representing the rule type.

Implements QgsAbstractLabelingEngineRule.

Definition at line 511 of file qgslabelingenginerule_impl.cpp.

◆ id()

QString QgsLabelingEngineRuleAvoidLabelOverlapWithFeature::id ( ) const

overridevirtual

Returns a string uniquely identifying the rule subclass.

Implements QgsAbstractLabelingEngineRule.

Definition at line 506 of file qgslabelingenginerule_impl.cpp.

◆ labeledLayer()

QgsMapLayer * QgsLabelingEngineRuleAvoidLabelOverlapWithFeature::labeledLayer ( ) const

Returns the layer providing the labels.

See also: setLabeledLayer()

Definition at line 621 of file qgslabelingenginerule_impl.cpp.

◆ prepare()

bool QgsLabelingEngineRuleAvoidLabelOverlapWithFeature::prepare ( QgsRenderContext & context )

overridevirtual

Prepares the rule.

This must be called on the main render thread, prior to commencing the render operation. Thread sensitive logic (such as creation of feature sources) can be performed in this method.

Implements QgsAbstractLabelingEngineRule.

Definition at line 529 of file qgslabelingenginerule_impl.cpp.

◆ readXml()

void QgsLabelingEngineRuleAvoidLabelOverlapWithFeature::readXml	(	const QDomElement &	element,
		const QgsReadWriteContext &	context
	)

overridevirtual

Reads the rule properties from an XML element.

See also: resolveReferences(); writeXml()

Implements QgsAbstractLabelingEngineRule.

Definition at line 557 of file qgslabelingenginerule_impl.cpp.

◆ resolveReferences()

void QgsLabelingEngineRuleAvoidLabelOverlapWithFeature::resolveReferences ( const QgsProject * project )

overridevirtual

Resolves reference to layers from stored layer ID.

Should be called following a call readXml().

Reimplemented from QgsAbstractLabelingEngineRule.

Definition at line 575 of file qgslabelingenginerule_impl.cpp.

◆ setLabeledLayer()

void QgsLabelingEngineRuleAvoidLabelOverlapWithFeature::setLabeledLayer ( QgsMapLayer * layer )

Sets the layer providing the labels.

See also: labeledLayer()

Definition at line 626 of file qgslabelingenginerule_impl.cpp.

◆ setTargetLayer()

void QgsLabelingEngineRuleAvoidLabelOverlapWithFeature::setTargetLayer ( QgsVectorLayer * layer )

Sets the layer providing the features which labels must not overlap.

See also: targetLayer()

Definition at line 636 of file qgslabelingenginerule_impl.cpp.

◆ targetLayer()

QgsVectorLayer * QgsLabelingEngineRuleAvoidLabelOverlapWithFeature::targetLayer ( ) const

Returns the layer providing the features which labels must not overlap.

See also: setTargetLayer()

Definition at line 631 of file qgslabelingenginerule_impl.cpp.

◆ writeXml()

void QgsLabelingEngineRuleAvoidLabelOverlapWithFeature::writeXml	(	QDomDocument &	doc,
		QDomElement &	element,
		const QgsReadWriteContext &	context
	)		const

overridevirtual

Writes the rule properties to an XML element.

See also: readXml()

Implements QgsAbstractLabelingEngineRule.

Definition at line 539 of file qgslabelingenginerule_impl.cpp.

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

/build/qgis-3.40.0+99sid/src/core/labeling/rules/qgslabelingenginerule_impl.h
/build/qgis-3.40.0+99sid/src/core/labeling/rules/qgslabelingenginerule_impl.cpp

Public Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ QgsLabelingEngineRuleAvoidLabelOverlapWithFeature()

◆ ~QgsLabelingEngineRuleAvoidLabelOverlapWithFeature()

Member Function Documentation

◆ candidateIsIllegal()

◆ clone()

◆ description()

◆ displayType()

◆ id()

◆ labeledLayer()

◆ prepare()

◆ readXml()

◆ resolveReferences()

◆ setLabeledLayer()

◆ setTargetLayer()

◆ targetLayer()

◆ writeXml()