An abstract interface for legend items returned from QgsMapLayerLegend implementation. More...

#include <qgslayertreemodellegendnode.h>

Inheritance diagram for QgsLayerTreeModelLegendNode:

[legend]

Classes
struct	ItemContext
struct	ItemMetrics

Public Types
enum class	CustomRole : int { RuleKey = Qt::UserRole , ParentRuleKey , NodeType , IsDataDefinedSize }
	Legend node data roles. More...
enum	NodeTypes { SimpleLegend , SymbolLegend , RasterSymbolLegend , ImageLegend , WmsLegend , DataDefinedSizeLegend , EmbeddedWidget , ColorRampLegend }
	Types of legend nodes. More...

Public Slots
void	checkAllItems ()
	Checks all checkable items belonging to the same layer as this node.
void	toggleAllItems ()
	Toggle all checkable items belonging to the same layer as this node.
void	uncheckAllItems ()
	Unchecks all checkable items belonging to the same layer as this node.

Signals
void	dataChanged ()
	Emitted on internal data change so the layer tree model can forward the signal to views.
void	sizeChanged ()
	Emitted when the size of this node changes.

Public Member Functions
virtual bool	columnBreak () const
	Returns whether a forced column break should occur before the node.
virtual QVariant	data (int role) const =0
	Returns data associated with the item. Must be implemented in derived class.
virtual ItemMetrics	draw (const QgsLegendSettings &settings, ItemContext &ctx)
	Entry point called from QgsLegendRenderer to do the rendering.
virtual QSizeF	drawSymbol (const QgsLegendSettings &settings, ItemContext *ctx, double itemHeight) const
	Draws symbol on the left side of the item.
virtual QSizeF	drawSymbolText (const QgsLegendSettings &settings, ItemContext *ctx, QSizeF symbolSize) const
	Draws label on the right side of the item.
virtual QJsonObject	exportSymbolToJson (const QgsLegendSettings &settings, const QgsRenderContext &context) const
	Adds a symbol in base64 string within a JSON object with the key "icon".
QJsonObject	exportToJson (const QgsLegendSettings &settings, const QgsRenderContext &context)
	Entry point called from QgsLegendRenderer to do the rendering in a JSON object.
virtual Qt::ItemFlags	flags () const
	Returns item flags associated with the item. Default implementation returns Qt::ItemIsEnabled.
virtual void	invalidateMapBasedData ()
	Notification from model that information from associated map view has changed.
virtual bool	isEmbeddedInParent () const
virtual bool	isScaleOK (double scale) const
QgsLayerTreeLayer *	layerNode () const
	Returns pointer to the parent layer node.
QgsLayerTreeModel *	model () const
	Returns pointer to model owning this legend node.
virtual void	setColumnBreak (bool breakBeforeNode)
	Sets whether a forced column break should occur before the node.
virtual bool	setData (const QVariant &value, int role)
	Sets some data associated with the item. Default implementation does nothing and returns `false`.
virtual void	setEmbeddedInParent (bool embedded)
virtual void	setUserLabel (const QString &userLabel)
virtual void	setUserPatchSize (QSizeF size)
	Sets the user (overridden) size for the legend node.
virtual QString	userLabel () const
virtual QSizeF	userPatchSize () const
	Returns the user (overridden) size for the legend node.

Protected Member Functions
	QgsLayerTreeModelLegendNode (QgsLayerTreeLayer nodeL, QObject parent=nullptr)
	Construct the node with pointer to its parent layer node.
QgsRenderContext *	createTemporaryRenderContext () const
	Returns a temporary context or `nullptr` if legendMapViewData are not valid.

Protected Attributes
bool	mColumnBreakBeforeNode = false
bool	mEmbeddedInParent = false
QgsLayerTreeLayer *	mLayerNode = nullptr
QgsLegendPatchShape	mPatchShape
QString	mUserLabel
QSizeF	mUserSize

Detailed Description

An abstract interface for legend items returned from QgsMapLayerLegend implementation.

The objects are used in QgsLayerTreeModel. Custom implementations may offer additional interactivity and customized look.

Definition at line 49 of file qgslayertreemodellegendnode.h.

Member Enumeration Documentation

◆ CustomRole

enum class QgsLayerTreeModelLegendNode::CustomRole : int

strong

Legend node data roles.

Note: Prior to QGIS 3.36 this was available as QgsLayerTreeModelLegendNode::LegendNodeRoles

Since: QGIS 3.36

Enumerator
RuleKey	Rule key of the node (QString).
ParentRuleKey	Rule key of the parent legend node - for legends with tree hierarchy (QString). Added in 2.8.
NodeType	Type of node. Added in 3.16.
IsDataDefinedSize	Set when a node is related to data defined size (title or separated legend items). Added in 3.38.

Definition at line 86 of file qgslayertreemodellegendnode.h.

◆ NodeTypes

enum QgsLayerTreeModelLegendNode::NodeTypes

Types of legend nodes.

Enumerator
SimpleLegend	Simple label with icon legend node type.
SymbolLegend	Vector symbol legend node type.
RasterSymbolLegend	Raster symbol legend node type.
ImageLegend	Raster image legend node type.
WmsLegend	WMS legend node type.
DataDefinedSizeLegend	Marker symbol legend node type.
EmbeddedWidget	Embedded widget placeholder node type.
ColorRampLegend	Color ramp legend. Since QGIS 3.18

Definition at line 97 of file qgslayertreemodellegendnode.h.

Constructor & Destructor Documentation

◆ QgsLayerTreeModelLegendNode()

QgsLayerTreeModelLegendNode::QgsLayerTreeModelLegendNode	(	QgsLayerTreeLayer *	nodeL,
		QObject *	parent = nullptr )

explicitprotected

Construct the node with pointer to its parent layer node.

Definition at line 50 of file qgslayertreemodellegendnode.cpp.

Member Function Documentation

◆ checkAllItems

void QgsLayerTreeModelLegendNode::checkAllItems ( )

slot

Checks all checkable items belonging to the same layer as this node.

See also: uncheckAllItems(); toggleAllItems()

Since: QGIS 3.18 (previously was available in QgsSymbolLegendNode subclass only)

Definition at line 283 of file qgslayertreemodellegendnode.cpp.

◆ columnBreak()

virtual bool QgsLayerTreeModelLegendNode::columnBreak ( ) const

inlinevirtual

Returns whether a forced column break should occur before the node.

See also: setColumnBreak()

Since: QGIS 3.14

Definition at line 166 of file qgslayertreemodellegendnode.h.

◆ createTemporaryRenderContext()

QgsRenderContext * QgsLayerTreeModelLegendNode::createTemporaryRenderContext ( ) const

protected

Returns a temporary context or nullptr if legendMapViewData are not valid.

Definition at line 490 of file qgslayertreemodellegendnode.cpp.

◆ data()

virtual QVariant QgsLayerTreeModelLegendNode::data ( int role ) const

pure virtual

Returns data associated with the item. Must be implemented in derived class.

Implemented in QgsColorRampLegendNode, QgsDataDefinedSizeLegendNode, QgsImageLegendNode, QgsRasterSymbolLegendNode, QgsSimpleLegendNode, QgsSymbolLegendNode, QgsVectorLabelLegendNode, and QgsWmsLegendNode.

◆ dataChanged

void QgsLayerTreeModelLegendNode::dataChanged ( )

signal

Emitted on internal data change so the layer tree model can forward the signal to views.

◆ draw()

QgsLayerTreeModelLegendNode::ItemMetrics QgsLayerTreeModelLegendNode::draw	(	const QgsLegendSettings &	settings,
		ItemContext &	ctx )

virtual

Entry point called from QgsLegendRenderer to do the rendering.

Default implementation calls drawSymbol() and drawSymbolText() methods.

Reimplemented in QgsDataDefinedSizeLegendNode.

Definition at line 90 of file qgslayertreemodellegendnode.cpp.

◆ drawSymbol()

QSizeF QgsLayerTreeModelLegendNode::drawSymbol	(	const QgsLegendSettings &	settings,
		ItemContext *	ctx,
		double	itemHeight ) const

virtual

Draws symbol on the left side of the item.

Parameters

settings	Legend layout configuration
ctx	Context for rendering - may be `nullptr` if only doing layout without actual rendering
itemHeight	Minimal height of the legend item - used for correct positioning when rendering

Returns: Real size of the symbol (may be bigger than "normal" symbol size from settings)

Reimplemented in QgsColorRampLegendNode, QgsImageLegendNode, QgsRasterSymbolLegendNode, QgsSymbolLegendNode, QgsVectorLabelLegendNode, and QgsWmsLegendNode.

Definition at line 141 of file qgslayertreemodellegendnode.cpp.

◆ drawSymbolText()

QSizeF QgsLayerTreeModelLegendNode::drawSymbolText	(	const QgsLegendSettings &	settings,
		ItemContext *	ctx,
		QSizeF	symbolSize ) const

virtual

Draws label on the right side of the item.

Parameters

settings	Legend layout configuration
ctx	Context for rendering - may be `nullptr` if only doing layout without actual rendering
symbolSize	Real size of the associated symbol - used for correct positioning when rendering

Returns: Size of the label (may span multiple lines)

Reimplemented in QgsColorRampLegendNode.

Definition at line 197 of file qgslayertreemodellegendnode.cpp.

◆ exportSymbolToJson()

QJsonObject QgsLayerTreeModelLegendNode::exportSymbolToJson	(	const QgsLegendSettings &	settings,
		const QgsRenderContext &	context ) const

virtual

Adds a symbol in base64 string within a JSON object with the key "icon".

Parameters

settings	Legend layout configuration
context	Rendering context

Since: QGIS 3.8

Reimplemented in QgsColorRampLegendNode, QgsImageLegendNode, QgsRasterSymbolLegendNode, QgsSymbolLegendNode, QgsVectorLabelLegendNode, and QgsWmsLegendNode.

Definition at line 180 of file qgslayertreemodellegendnode.cpp.

◆ exportToJson()

QJsonObject QgsLayerTreeModelLegendNode::exportToJson	(	const QgsLegendSettings &	settings,
		const QgsRenderContext &	context )

Entry point called from QgsLegendRenderer to do the rendering in a JSON object.

Parameters

settings	Legend layout configuration
context	Rendering context

Since: QGIS 3.8

Definition at line 133 of file qgslayertreemodellegendnode.cpp.

◆ flags()

Qt::ItemFlags QgsLayerTreeModelLegendNode::flags ( ) const

virtual

Returns item flags associated with the item. Default implementation returns Qt::ItemIsEnabled.

Reimplemented in QgsRasterSymbolLegendNode, and QgsSymbolLegendNode.

Definition at line 61 of file qgslayertreemodellegendnode.cpp.

◆ invalidateMapBasedData()

virtual void QgsLayerTreeModelLegendNode::invalidateMapBasedData ( )

inlinevirtual

Notification from model that information from associated map view has changed.

Default implementation does nothing.

Reimplemented in QgsSymbolLegendNode, and QgsWmsLegendNode.

Definition at line 174 of file qgslayertreemodellegendnode.h.

◆ isEmbeddedInParent()

virtual bool QgsLayerTreeModelLegendNode::isEmbeddedInParent ( ) const

inlinevirtual

Definition at line 124 of file qgslayertreemodellegendnode.h.

◆ isScaleOK()

virtual bool QgsLayerTreeModelLegendNode::isScaleOK ( double scale ) const

inlinevirtual

Reimplemented in QgsSymbolLegendNode.

Definition at line 168 of file qgslayertreemodellegendnode.h.

◆ layerNode()

QgsLayerTreeLayer * QgsLayerTreeModelLegendNode::layerNode ( ) const

inline

Returns pointer to the parent layer node.

Definition at line 110 of file qgslayertreemodellegendnode.h.

◆ model()

QgsLayerTreeModel * QgsLayerTreeModelLegendNode::model ( ) const

Returns pointer to model owning this legend node.

Definition at line 56 of file qgslayertreemodellegendnode.cpp.

◆ setColumnBreak()

virtual void QgsLayerTreeModelLegendNode::setColumnBreak ( bool breakBeforeNode )

inlinevirtual

Sets whether a forced column break should occur before the node.

See also: columnBreak()

Since: QGIS 3.14

Definition at line 158 of file qgslayertreemodellegendnode.h.

◆ setData()

bool QgsLayerTreeModelLegendNode::setData	(	const QVariant &	value,
		int	role )

virtual

Sets some data associated with the item. Default implementation does nothing and returns false.

Reimplemented in QgsRasterSymbolLegendNode, and QgsSymbolLegendNode.

Definition at line 66 of file qgslayertreemodellegendnode.cpp.

◆ setEmbeddedInParent()

virtual void QgsLayerTreeModelLegendNode::setEmbeddedInParent ( bool embedded )

inlinevirtual

Reimplemented in QgsSymbolLegendNode.

Definition at line 125 of file qgslayertreemodellegendnode.h.

◆ setUserLabel()

virtual void QgsLayerTreeModelLegendNode::setUserLabel ( const QString & userLabel )

inlinevirtual

Reimplemented in QgsSymbolLegendNode.

Definition at line 128 of file qgslayertreemodellegendnode.h.

◆ setUserPatchSize()

void QgsLayerTreeModelLegendNode::setUserPatchSize ( QSizeF size )

virtual

Sets the user (overridden) size for the legend node.

If either the width or height are non-zero, they will be used when rendering the legend node instead of the default symbol width or height from QgsLegendSettings.

See also: userPatchSize()

Since: QGIS 3.14

Definition at line 81 of file qgslayertreemodellegendnode.cpp.

◆ sizeChanged

void QgsLayerTreeModelLegendNode::sizeChanged ( )

signal

Emitted when the size of this node changes.

Since: QGIS 3.16

◆ toggleAllItems

void QgsLayerTreeModelLegendNode::toggleAllItems ( )

slot

Toggle all checkable items belonging to the same layer as this node.

See also: checkAllItems(); uncheckAllItems()

Since: QGIS 3.18 (previously was available in QgsSymbolLegendNode subclass only)

Definition at line 293 of file qgslayertreemodellegendnode.cpp.

◆ uncheckAllItems

void QgsLayerTreeModelLegendNode::uncheckAllItems ( )

slot

Unchecks all checkable items belonging to the same layer as this node.

See also: checkAllItems(); toggleAllItems()

Since: QGIS 3.18 (previously was available in QgsSymbolLegendNode subclass only)

Definition at line 288 of file qgslayertreemodellegendnode.cpp.

◆ userLabel()

virtual QString QgsLayerTreeModelLegendNode::userLabel ( ) const

inlinevirtual

Definition at line 127 of file qgslayertreemodellegendnode.h.

◆ userPatchSize()

QSizeF QgsLayerTreeModelLegendNode::userPatchSize ( ) const

virtual

Returns the user (overridden) size for the legend node.

If either the width or height are non-zero, they will be used when rendering the legend node instead of the default symbol width or height from QgsLegendSettings.

See also: setUserPatchSize()

Since: QGIS 3.14

Definition at line 73 of file qgslayertreemodellegendnode.cpp.

Member Data Documentation

◆ mColumnBreakBeforeNode

bool QgsLayerTreeModelLegendNode::mColumnBreakBeforeNode = false

protected

Definition at line 372 of file qgslayertreemodellegendnode.h.

◆ mEmbeddedInParent

bool QgsLayerTreeModelLegendNode::mEmbeddedInParent = false

protected

Definition at line 368 of file qgslayertreemodellegendnode.h.

◆ mLayerNode

QgsLayerTreeLayer* QgsLayerTreeModelLegendNode::mLayerNode = nullptr

protected

Definition at line 367 of file qgslayertreemodellegendnode.h.

◆ mPatchShape

QgsLegendPatchShape QgsLayerTreeModelLegendNode::mPatchShape

protected

Definition at line 370 of file qgslayertreemodellegendnode.h.

◆ mUserLabel

QString QgsLayerTreeModelLegendNode::mUserLabel

protected

Definition at line 369 of file qgslayertreemodellegendnode.h.

◆ mUserSize

QSizeF QgsLayerTreeModelLegendNode::mUserSize

protected

Definition at line 371 of file qgslayertreemodellegendnode.h.

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

/build/qgis-3.99.0+git20251210+2fe06baccd8+99sid/src/core/layertree/qgslayertreemodellegendnode.h
/build/qgis-3.99.0+git20251210+2fe06baccd8+99sid/src/core/layertree/qgslayertreemodellegendnode.cpp

Classes

Public Types

Public Slots

Signals

Public Member Functions

Protected Member Functions

Protected Attributes

Detailed Description

Member Enumeration Documentation

◆ CustomRole

◆ NodeTypes

Constructor & Destructor Documentation

◆ QgsLayerTreeModelLegendNode()

Member Function Documentation

◆ checkAllItems

◆ columnBreak()

◆ createTemporaryRenderContext()

◆ data()

◆ dataChanged

◆ draw()

◆ drawSymbol()

◆ drawSymbolText()

◆ exportSymbolToJson()

◆ exportToJson()

◆ flags()

◆ invalidateMapBasedData()

◆ isEmbeddedInParent()

◆ isScaleOK()

◆ layerNode()

◆ model()

◆ setColumnBreak()

◆ setData()

◆ setEmbeddedInParent()

◆ setUserLabel()

◆ setUserPatchSize()

◆ sizeChanged

◆ toggleAllItems

◆ uncheckAllItems

◆ userLabel()

◆ userPatchSize()

Member Data Documentation

◆ mColumnBreakBeforeNode

◆ mEmbeddedInParent

◆ mLayerNode

◆ mPatchShape

◆ mUserLabel

◆ mUserSize