Null symbol renderer. More...

#include <qgsnullsymbolrenderer.h>

Inheritance diagram for QgsNullSymbolRenderer:

Public Member Functions
	QgsNullSymbolRenderer ()

virtual	~QgsNullSymbolRenderer ()

virtual QgsFeatureRendererV2 *	clone () const override

virtual QString	dump () const override
	for debugging More...

virtual QgsSymbolV2 *	originalSymbolForFeature (QgsFeature &feature, QgsRenderContext &context) override
	Return symbol for feature. More...

virtual bool	renderFeature (QgsFeature &feature, QgsRenderContext &context, int layer=-1, bool selected=false, bool drawVertexMarker=false) override
	Render a feature using this renderer in the given context. More...

virtual QDomElement	save (QDomDocument &doc) override
	store renderer info to XML element More...

virtual void	startRender (QgsRenderContext &context, const QgsFields &fields) override
	Needs to be called when a new render cycle is started. More...

virtual void	stopRender (QgsRenderContext &context) override
	Needs to be called when a render cycle has finished to clean up. More...

virtual QgsSymbolV2 *	symbolForFeature (QgsFeature &feature, QgsRenderContext &context) override
	To be overridden. More...

virtual QgsSymbolV2List	symbols (QgsRenderContext &context) override
	Returns list of symbols used by the renderer. More...

virtual QList< QString >	usedAttributes () override
	Returns a set of attributes required for this renderer. More...

virtual bool	willRenderFeature (QgsFeature &feat, QgsRenderContext &context) override
	Returns whether the renderer will render a feature or not. More...

Public Member Functions inherited from QgsFeatureRendererV2
virtual	~QgsFeatureRendererV2 ()

virtual int	capabilities ()
	returns bitwise OR-ed capabilities of the renderer More...

virtual void	checkLegendSymbolItem (const QString &key, bool state=true)
	item in symbology was checked More...

virtual const QgsFeatureRendererV2 *	embeddedRenderer () const
	Returns the current embedded renderer (subrenderer) for this feature renderer. More...

virtual QString	filter (const QgsFields &fields=QgsFields())
	If a renderer does not require all the features this method may be overridden and return an expression used as where clause. More...

virtual bool	filterNeedsGeometry () const
	Returns true if this renderer requires the geometry to apply the filter. More...

bool	forceRasterRender () const
	Returns whether the renderer must render as a raster. More...

virtual QString	legendClassificationAttribute () const
	If supported by the renderer, return classification attribute for the use in legend. More...

virtual QSet< QString >	legendKeysForFeature (QgsFeature &feature, QgsRenderContext &context)
	Return legend keys matching a specified feature. More...

virtual bool	legendSymbolItemChecked (const QString &key)
	items of symbology items in legend is checked More...

virtual QgsLegendSymbolList	legendSymbolItems (double scaleDenominator=-1, const QString &rule="")
	return a list of item text / symbol More...

virtual bool	legendSymbolItemsCheckable () const
	items of symbology items in legend should be checkable More...

virtual QgsLegendSymbolListV2	legendSymbolItemsV2 () const
	Return a list of symbology items for the legend. More...

virtual QgsLegendSymbologyList	legendSymbologyItems (QSize iconSize)
	return a list of symbology items for the legend More...

virtual void	modifyRequestExtent (QgsRectangle &extent, QgsRenderContext &context)
	Allows for a renderer to modify the extent of a feature request prior to rendering. More...

QgsFeatureRequest::OrderBy	orderBy () const
	Get the order in which features shall be processed by this renderer. More...

bool	orderByEnabled () const
	Returns whether custom ordering will be applied before features are processed by this renderer. More...

virtual Q_DECL_DEPRECATED QgsSymbolV2 *	originalSymbolForFeature (QgsFeature &feature)
	Return symbol for feature. More...

virtual Q_DECL_DEPRECATED QgsSymbolV2List	originalSymbolsForFeature (QgsFeature &feat)
	Equivalent of originalSymbolsForFeature() call extended to support renderers that may use more symbols per feature - similar to symbolsForFeature() More...

virtual QgsSymbolV2List	originalSymbolsForFeature (QgsFeature &feat, QgsRenderContext &context)
	Equivalent of originalSymbolsForFeature() call extended to support renderers that may use more symbols per feature - similar to symbolsForFeature() More...

QgsPaintEffect *	paintEffect () const
	Returns the current paint effect for the renderer. More...

virtual Q_DECL_DEPRECATED QString	rotationField () const
	return rotation field name (or empty string if not set or not supported by renderer) More...

virtual void	setEmbeddedRenderer (QgsFeatureRendererV2 *subRenderer)
	Sets an embedded renderer (subrenderer) for this feature renderer. More...

void	setForceRasterRender (bool forceRaster)
	Sets whether the renderer should be rendered to a raster destination. More...

virtual void	setLegendSymbolItem (const QString &key, QgsSymbolV2 *symbol)
	Sets the symbol to be used for a legend symbol item. More...

void	setOrderBy (const QgsFeatureRequest::OrderBy &orderBy)
	Define the order in which features shall be processed by this renderer. More...

void	setOrderByEnabled (bool enabled)
	Sets whether custom ordering should be applied before features are processed by this renderer. More...

void	setPaintEffect (QgsPaintEffect *effect)
	Sets the current paint effect for the renderer. More...

virtual Q_DECL_DEPRECATED void	setRotationField (const QString &fieldName)
	sets rotation field of renderer (if supported by the renderer) More...

void	setUsingSymbolLevels (bool usingSymbolLevels)

void	setVertexMarkerAppearance (int type, int size)
	set type and size of editing vertex markers for subsequent rendering More...

virtual Q_DECL_DEPRECATED void	startRender (QgsRenderContext &context, const QgsVectorLayer *vlayer)

virtual Q_DECL_DEPRECATED QgsSymbolV2 *	symbolForFeature (QgsFeature &feature)
	To be overridden. More...

virtual Q_DECL_DEPRECATED QgsSymbolV2List	symbols ()
	For symbol levels. More...

virtual Q_DECL_DEPRECATED QgsSymbolV2List	symbolsForFeature (QgsFeature &feat)
	Returns list of symbols used for rendering the feature. More...

virtual QgsSymbolV2List	symbolsForFeature (QgsFeature &feat, QgsRenderContext &context)
	Returns list of symbols used for rendering the feature. More...

virtual void	toSld (QDomDocument &doc, QDomElement &element) const
	used from subclasses to create SLD Rule elements following SLD v1.1 specs More...

virtual void	toSld (QDomDocument &doc, QDomElement &element, const QgsStringMap &props) const
	used from subclasses to create SLD Rule elements following SLD v1.1 specs More...

QString	type () const

bool	usingSymbolLevels () const

virtual Q_DECL_DEPRECATED bool	willRenderFeature (QgsFeature &feat)
	Returns whether the renderer will render a feature or not. More...

virtual Q_DECL_DEPRECATED QDomElement	writeSld (QDomDocument &doc, const QgsVectorLayer &layer) const
	create the SLD UserStyle element following the SLD v1.1 specs More...

virtual QDomElement	writeSld (QDomDocument &doc, const QString &styleName) const
	create the SLD UserStyle element following the SLD v1.1 specs with the given name More...

virtual QDomElement	writeSld (QDomDocument &doc, const QString &styleName, const QgsStringMap &props) const
	create the SLD UserStyle element following the SLD v1.1 specs with the given name More...

Static Public Member Functions
static QgsNullSymbolRenderer *	convertFromRenderer (const QgsFeatureRendererV2 *renderer)
	Creates a QgsNullSymbolRenderer from an existing renderer. More...

static QgsFeatureRendererV2 *	create (QDomElement &element)
	Creates a null renderer from XML element. More...

Static Public Member Functions inherited from QgsFeatureRendererV2
static QgsFeatureRendererV2 *	defaultRenderer (QGis::GeometryType geomType)
	return a new renderer - used by default in vector layers More...

static QgsFeatureRendererV2 *	load (QDomElement &symbologyElem)
	create a renderer from XML element More...

static QgsFeatureRendererV2 *	loadSld (const QDomNode &node, QGis::GeometryType geomType, QString &errorMessage)
	Create a new renderer according to the information contained in the UserStyle element of a SLD style document. More...

Additional Inherited Members
Public Types inherited from QgsFeatureRendererV2
enum	Capabilities { SymbolLevels = 1, RotationField = 1 << 1, MoreSymbolsPerFeature = 1 << 2, Filter = 1 << 3, ScaleDependent = 1 << 4 }

Protected Member Functions inherited from QgsFeatureRendererV2
	QgsFeatureRendererV2 (const QString &type)

Q_DECL_DEPRECATED void	copyPaintEffect (QgsFeatureRendererV2 *destRenderer) const
	Copies paint effect of this renderer to another renderer. More...

void	copyRendererData (QgsFeatureRendererV2 *destRenderer) const
	Clones generic renderer data to another renderer. More...

void	renderFeatureWithSymbol (QgsFeature &feature, QgsSymbolV2 *symbol, QgsRenderContext &context, int layer, bool selected, bool drawVertexMarker)

void	renderVertexMarker (QPointF pt, QgsRenderContext &context)
	render editing vertex marker at specified point More...

void	renderVertexMarkerPolygon (QPolygonF &pts, QList< QPolygonF > *rings, QgsRenderContext &context)
	render editing vertex marker for a polygon More...

void	renderVertexMarkerPolyline (QPolygonF &pts, QgsRenderContext &context)
	render editing vertex marker for a polyline More...

void	setScaleMethodToSymbol (QgsSymbolV2 *symbol, int scaleMethod)

Static Protected Member Functions inherited from QgsFeatureRendererV2
static QgsConstWkbPtr	_getLineString (QPolygonF &pts, QgsRenderContext &context, QgsConstWkbPtr &wkb, bool clipToExtent=true)
	Creates a line string in screen coordinates from a wkb string in map coordinates. More...

static QgsConstWkbPtr	_getPoint (QPointF &pt, QgsRenderContext &context, QgsConstWkbPtr &wkb)
	Creates a point in screen coordinates from a wkb string in map coordinates. More...

static QgsConstWkbPtr	_getPolygon (QPolygonF &pts, QList< QPolygonF > &holes, QgsRenderContext &context, QgsConstWkbPtr &wkb, bool clipToExtent=true)
	Creates a polygon in screen coordinates from a wkb string in map coordinates. More...

static void	convertSymbolRotation (QgsSymbolV2 *symbol, const QString &field)

static void	convertSymbolSizeScale (QgsSymbolV2 *symbol, QgsSymbolV2::ScaleMethod method, const QString &field)

Protected Attributes inherited from QgsFeatureRendererV2
int	mCurrentVertexMarkerSize
	The current size of editing marker. More...

int	mCurrentVertexMarkerType
	The current type of editing marker. More...

bool	mForceRaster

QgsFeatureRequest::OrderBy	mOrderBy

bool	mOrderByEnabled

QgsPaintEffect *	mPaintEffect

QString	mType

bool	mUsingSymbolLevels

Detailed Description

Null symbol renderer.

Renderer which draws no symbols for features by default, but allows for labeling and diagrams for the layer. Selected features will also be drawn with a default symbol.

Note: Added in version 2.16

Definition at line 29 of file qgsnullsymbolrenderer.h.

Constructor & Destructor Documentation

◆ QgsNullSymbolRenderer()

QgsNullSymbolRenderer::QgsNullSymbolRenderer ( )

Definition at line 22 of file qgsnullsymbolrenderer.cpp.

◆ ~QgsNullSymbolRenderer()

QgsNullSymbolRenderer::~QgsNullSymbolRenderer ( )

virtual

Definition at line 27 of file qgsnullsymbolrenderer.cpp.

Member Function Documentation

◆ clone()

QgsFeatureRendererV2 * QgsNullSymbolRenderer::clone ( ) const

overridevirtual

Implements QgsFeatureRendererV2.

Definition at line 96 of file qgsnullsymbolrenderer.cpp.

◆ convertFromRenderer()

QgsNullSymbolRenderer * QgsNullSymbolRenderer::convertFromRenderer ( const QgsFeatureRendererV2 * renderer )

static

Creates a QgsNullSymbolRenderer from an existing renderer.

Parameters

renderer renderer to convert from

Returns: a new renderer if the conversion was possible, otherwise nullptr.

Definition at line 121 of file qgsnullsymbolrenderer.cpp.

◆ create()

QgsFeatureRendererV2 * QgsNullSymbolRenderer::create ( QDomElement & element )

static

Creates a null renderer from XML element.

Parameters

element DOM element

Returns: new null symbol renderer

Definition at line 107 of file qgsnullsymbolrenderer.cpp.

◆ dump()

QString QgsNullSymbolRenderer::dump ( ) const

overridevirtual

for debugging

Reimplemented from QgsFeatureRendererV2.

Definition at line 91 of file qgsnullsymbolrenderer.cpp.

◆ originalSymbolForFeature()

QgsSymbolV2 * QgsNullSymbolRenderer::originalSymbolForFeature	(	QgsFeature &	feature,
		QgsRenderContext &	context
	)

overridevirtual

Return symbol for feature.

The difference compared to symbolForFeature() is that it returns original symbol which can be used as an identifier for renderer's rule - the former may return a temporary replacement of a symbol for use in rendering.

Note: added in 2.12; available in Python bindings as originalSymbolForFeature2

Reimplemented from QgsFeatureRendererV2.

Definition at line 36 of file qgsnullsymbolrenderer.cpp.

◆ renderFeature()

bool QgsNullSymbolRenderer::renderFeature	(	QgsFeature &	feature,
		QgsRenderContext &	context,
		int	layer = `-1`,
		bool	selected = `false`,
		bool	drawVertexMarker = `false`
	)

overridevirtual

Render a feature using this renderer in the given context.

Must be called between startRender() and stopRender() calls. Default implementation renders a symbol as determined by symbolForFeature() call. Returns true if the feature has been returned (this is used for example to determine whether the feature may be labelled).

If layer is not -1, the renderer should draw only a particula layer from symbols (in order to support symbol level rendering).

Reimplemented from QgsFeatureRendererV2.

Definition at line 41 of file qgsnullsymbolrenderer.cpp.

◆ save()

QDomElement QgsNullSymbolRenderer::save ( QDomDocument & doc )

overridevirtual

store renderer info to XML element

Reimplemented from QgsFeatureRendererV2.

Definition at line 114 of file qgsnullsymbolrenderer.cpp.

◆ startRender()

void QgsNullSymbolRenderer::startRender	(	QgsRenderContext &	context,
		const QgsFields &	fields
	)

overridevirtual

Needs to be called when a new render cycle is started.

Parameters

context	Additional information passed to the renderer about the job which will be rendered
fields	The fields available for rendering

Returns: Information passed back from the renderer that can e.g. be used to reduce the amount of requested features

Implements QgsFeatureRendererV2.

Definition at line 66 of file qgsnullsymbolrenderer.cpp.

◆ stopRender()

void QgsNullSymbolRenderer::stopRender ( QgsRenderContext & context )

overridevirtual

Needs to be called when a render cycle has finished to clean up.

Implements QgsFeatureRendererV2.

Definition at line 72 of file qgsnullsymbolrenderer.cpp.

◆ symbolForFeature()

QgsSymbolV2 * QgsNullSymbolRenderer::symbolForFeature	(	QgsFeature &	feature,
		QgsRenderContext &	context
	)

overridevirtual

To be overridden.

Must be called between startRender() and stopRender() calls.

Parameters

feature	feature
context	render context

Returns: returns pointer to symbol or 0 if symbol was not found

Note: added in QGIS 2.12; available in Python bindings as symbolForFeature2

Reimplemented from QgsFeatureRendererV2.

Definition at line 31 of file qgsnullsymbolrenderer.cpp.

◆ symbols()

QgsSymbolV2List QgsNullSymbolRenderer::symbols ( QgsRenderContext & context )

overridevirtual

Returns list of symbols used by the renderer.

Parameters

context render context

Note: added in QGIS 2.12; available in Python bindings as symbols2

Reimplemented from QgsFeatureRendererV2.

Definition at line 102 of file qgsnullsymbolrenderer.cpp.

◆ usedAttributes()

QList< QString > QgsNullSymbolRenderer::usedAttributes ( )

overridevirtual

Returns a set of attributes required for this renderer.

TODO QGIS3: Change QList to QSet

Implements QgsFeatureRendererV2.

Definition at line 86 of file qgsnullsymbolrenderer.cpp.

◆ willRenderFeature()

bool QgsNullSymbolRenderer::willRenderFeature	(	QgsFeature &	feat,
		QgsRenderContext &	context
	)

overridevirtual

Returns whether the renderer will render a feature or not.

Must be called between startRender() and stopRender() calls. Default implementation uses symbolForFeature().

Note: added in QGIS 2.12; available in Python bindings as willRenderFeature2

Reimplemented from QgsFeatureRendererV2.

Definition at line 80 of file qgsnullsymbolrenderer.cpp.

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

/tmp/buildd/qgis-2.18.21+99unstable/src/core/symbology-ng/qgsnullsymbolrenderer.h
/tmp/buildd/qgis-2.18.21+99unstable/src/core/symbology-ng/qgsnullsymbolrenderer.cpp

Public Member Functions

Static Public Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ QgsNullSymbolRenderer()

◆ ~QgsNullSymbolRenderer()

Member Function Documentation

◆ clone()

◆ convertFromRenderer()

◆ create()

◆ dump()

◆ originalSymbolForFeature()

◆ renderFeature()

◆ save()

◆ startRender()

◆ stopRender()

◆ symbolForFeature()

◆ symbols()

◆ usedAttributes()

◆ willRenderFeature()