QgsFeatureExpressionFilterProvider Class Reference

A feature filter provider allowing to set filter expressions on a per-layer basis. More...

#include <qgsfeatureexpressionfilterprovider.h>

Inheritance diagram for QgsFeatureExpressionFilterProvider:

Public Member Functions
	QgsFeatureExpressionFilterProvider ()=default
	Constructor.
QgsFeatureExpressionFilterProvider *	clone () const override
	Create a clone of the feature filter provider.
Q_DECL_DEPRECATED void	filterFeatures (const QgsVectorLayer *layer, QgsFeatureRequest &filterFeatures) const override
	Add additional filters to the feature request to further restrict the features returned by the request.
void	filterFeatures (const QString &layerId, QgsFeatureRequest &filterFeatures) const override
	Add additional filters to the feature request to further restrict the features returned by the request.
QStringList	layerAttributes (const QgsVectorLayer *layer, const QStringList &attributes) const override
	Returns the list of visible attribute names from a list of attributes names for the given layer.
void	setFilter (const QString &layerId, const QgsExpression &expression)
	Set a filter for the given layer.
Public Member Functions inherited from QgsFeatureFilterProvider
	QgsFeatureFilterProvider ()=default
virtual	~QgsFeatureFilterProvider ()=default
virtual Q_DECL_DEPRECATED bool	isFilterThreadSafe () const
	Returns true if the filterFeature function is thread safe, which will lead to reliance on layer ID instead of the raw layer pointer.

Detailed Description

A feature filter provider allowing to set filter expressions on a per-layer basis.

Since

QGIS 4.0

Definition at line 34 of file qgsfeatureexpressionfilterprovider.h.

Constructor & Destructor Documentation

QgsFeatureExpressionFilterProvider()

QgsFeatureExpressionFilterProvider::QgsFeatureExpressionFilterProvider ( )

default

Constructor.

Member Function Documentation

clone()

QgsFeatureExpressionFilterProvider * QgsFeatureExpressionFilterProvider::clone ( ) const

overridevirtual

Create a clone of the feature filter provider.

Returns

a new clone

Implements QgsFeatureFilterProvider.

Definition at line 43 of file qgsfeatureexpressionfilterprovider.cpp.

filterFeatures() [1/2]

void QgsFeatureExpressionFilterProvider::filterFeatures ( const QgsVectorLayer *  layer, QgsFeatureRequest &  featureRequest  ) const

overridevirtual

Add additional filters to the feature request to further restrict the features returned by the request.

Derived classes must implement this method.

Parameters

layer	the layer to filter
featureRequest	the feature request to update

Deprecated:

QGIS 4.0. Use the layer ID variant.

Reimplemented from QgsFeatureFilterProvider.

Definition at line 23 of file qgsfeatureexpressionfilterprovider.cpp.

filterFeatures() [2/2]

void QgsFeatureExpressionFilterProvider::filterFeatures ( const QString &  layerId, QgsFeatureRequest &  featureRequest  ) const

overridevirtual

Add additional filters to the feature request to further restrict the features returned by the request.

Derived classes must implement this method.

Parameters

layerId	the layer ID to filter
featureRequest	the feature request to update

Since

QGIS 4.0

Reimplemented from QgsFeatureFilterProvider.

Definition at line 28 of file qgsfeatureexpressionfilterprovider.cpp.

layerAttributes()

QStringList QgsFeatureExpressionFilterProvider::layerAttributes ( const QgsVectorLayer *  layer, const QStringList &  attributes  ) const

overridevirtual

Returns the list of visible attribute names from a list of attributes names for the given layer.

Since

QGIS 3.18

Implements QgsFeatureFilterProvider.

Definition at line 37 of file qgsfeatureexpressionfilterprovider.cpp.

setFilter()

void QgsFeatureExpressionFilterProvider::setFilter	(	const QString &	layerId,
		const QgsExpression &	expression
	)

Set a filter for the given layer.

Parameters

layerId	the layer to filter
expression	the filter expression

Definition at line 50 of file qgsfeatureexpressionfilterprovider.cpp.

---

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

• /build/qgis-3.99.0+git20250718+f78f5286a64+99sid/src/core/qgsfeatureexpressionfilterprovider.h
• /build/qgis-3.99.0+git20250718+f78f5286a64+99sid/src/core/qgsfeatureexpressionfilterprovider.cpp