QgsFeatureSource subclass which proxies methods to an underlying QgsFeatureSource, modifying results according to the settings in a QgsProcessingContext. More...

#include <qgsprocessingutils.h>

Inheritance diagram for QgsProcessingFeatureSource:

[legend]

Public Member Functions
	QgsProcessingFeatureSource (QgsFeatureSource *originalSource, const QgsProcessingContext &context, bool ownsOriginalSource=false, long long featureLimit=-1, const QString &filterExpression=QString())
	Constructor for QgsProcessingFeatureSource, accepting an original feature source originalSource and processing context.

	~QgsProcessingFeatureSource () override

QgsFeatureIds	allFeatureIds () const override
	Returns a list of all feature IDs for features present in the source.

QgsExpressionContextScope *	createExpressionContextScope () const
	Returns an expression context scope suitable for this source.

long long	featureCount () const override
	Returns the number of features contained in the source, or -1 if the feature count is unknown.

QgsFields	fields () const override
	Returns the fields associated with features in the source.

QgsFeatureIterator	getFeatures (const QgsFeatureRequest &request, Qgis::ProcessingFeatureSourceFlags flags) const
	Returns an iterator for the features in the source, respecting the supplied feature flags.

QgsFeatureIterator	getFeatures (const QgsFeatureRequest &request=QgsFeatureRequest()) const override
	Returns an iterator for the features in the source.

Qgis::FeatureAvailability	hasFeatures () const override
	Determines if there are any features available in the source.

Qgis::SpatialIndexPresence	hasSpatialIndex () const override
	Returns an enum value representing the presence of a valid spatial index on the source, if it can be determined.

Qgis::InvalidGeometryCheck	invalidGeometryCheck () const
	Returns the geometry check method for the source.

QVariant	maximumValue (int fieldIndex) const override
	Returns the maximum value for an attribute column or an invalid variant in case of error.

QVariant	minimumValue (int fieldIndex) const override
	Returns the minimum value for an attribute column or an invalid variant in case of error.

void	setInvalidGeometryCheck (Qgis::InvalidGeometryCheck method)
	Overrides the default geometry check method for the source.

QgsCoordinateReferenceSystem	sourceCrs () const override
	Returns the coordinate reference system for features in the source.

QgsRectangle	sourceExtent () const override
	Returns the extent of all geometries from the source.

QString	sourceName () const override
	Returns a friendly display name for the source.

QSet< QVariant >	uniqueValues (int fieldIndex, int limit=-1) const override
	Returns the set of unique values contained within the specified fieldIndex from this source.

Qgis::WkbType	wkbType () const override
	Returns the geometry type for features returned by this source.

Public Member Functions inherited from QgsFeatureSource
virtual	~QgsFeatureSource ()=default

QgsVectorLayer *	materialize (const QgsFeatureRequest &request, QgsFeedback *feedback=nullptr)
	Materializes a request (query) made against this feature source, by running it over the source and returning a new memory based vector layer containing the result.

virtual QgsBox3D	sourceExtent3D () const
	Returns the 3D extent of all geometries from the source.

Detailed Description

QgsFeatureSource subclass which proxies methods to an underlying QgsFeatureSource, modifying results according to the settings in a QgsProcessingContext.

Definition at line 685 of file qgsprocessingutils.h.

Constructor & Destructor Documentation

◆ QgsProcessingFeatureSource()

QgsProcessingFeatureSource::QgsProcessingFeatureSource	(	QgsFeatureSource *	originalSource,
		const QgsProcessingContext &	context,
		bool	ownsOriginalSource = `false`,
		long long	featureLimit = `-1`,
		const QString &	filterExpression = `QString()`
	)

Constructor for QgsProcessingFeatureSource, accepting an original feature source originalSource and processing context.

Ownership of originalSource is dictated by ownsOriginalSource. If ownsOriginalSource is false, ownership is not transferred, and callers must ensure that originalSource exists for the lifetime of this object. If ownsOriginalSource is true, then this object will take ownership of originalSource.

If featureLimit is set to a value > 0, then a limit is placed on the maximum number of features which will be read from the source.

Since QGIS 3.32, the optional filterExpression can be used to specify an expression based filter for the source.

Definition at line 1715 of file qgsprocessingutils.cpp.

◆ ~QgsProcessingFeatureSource()

QgsProcessingFeatureSource::~QgsProcessingFeatureSource ( )

override

Definition at line 1735 of file qgsprocessingutils.cpp.

Member Function Documentation

◆ allFeatureIds()

QgsFeatureIds QgsProcessingFeatureSource::allFeatureIds ( ) const

overridevirtual

Returns a list of all feature IDs for features present in the source.

Reimplemented from QgsFeatureSource.

Definition at line 1914 of file qgsprocessingutils.cpp.

◆ createExpressionContextScope()

QgsExpressionContextScope * QgsProcessingFeatureSource::createExpressionContextScope ( ) const

Returns an expression context scope suitable for this source.

Definition at line 1940 of file qgsprocessingutils.cpp.

◆ featureCount()

long long QgsProcessingFeatureSource::featureCount ( ) const

overridevirtual

Returns the number of features contained in the source, or -1 if the feature count is unknown.

Implements QgsFeatureSource.

Definition at line 1810 of file qgsprocessingutils.cpp.

◆ fields()

QgsFields QgsProcessingFeatureSource::fields ( ) const

overridevirtual

Returns the fields associated with features in the source.

Implements QgsFeatureSource.

Definition at line 1800 of file qgsprocessingutils.cpp.

◆ getFeatures() [1/2]

QgsFeatureIterator QgsProcessingFeatureSource::getFeatures	(	const QgsFeatureRequest &	request,
		Qgis::ProcessingFeatureSourceFlags	flags
	)		const

Returns an iterator for the features in the source, respecting the supplied feature flags.

An optional request can be used to optimise the returned iterator, eg by restricting the returned attributes or geometry.

Definition at line 1741 of file qgsprocessingutils.cpp.

◆ getFeatures() [2/2]

QgsFeatureIterator QgsProcessingFeatureSource::getFeatures ( const QgsFeatureRequest & request = QgsFeatureRequest() ) const

overridevirtual

Returns an iterator for the features in the source.

An optional request can be used to optimise the returned iterator, eg by restricting the returned attributes or geometry.

Implements QgsFeatureSource.

Definition at line 1777 of file qgsprocessingutils.cpp.

◆ hasFeatures()

Qgis::FeatureAvailability QgsProcessingFeatureSource::hasFeatures ( ) const

overridevirtual

Determines if there are any features available in the source.

Since: QGIS 3.2

Reimplemented from QgsFeatureSource.

Definition at line 1765 of file qgsprocessingutils.cpp.

◆ hasSpatialIndex()

Qgis::SpatialIndexPresence QgsProcessingFeatureSource::hasSpatialIndex ( ) const

overridevirtual

Returns an enum value representing the presence of a valid spatial index on the source, if it can be determined.

If QgsFeatureSource::SpatialIndexUnknown is returned then the presence of an index cannot be determined.

Since: QGIS 3.10.1

Reimplemented from QgsFeatureSource.

Definition at line 1935 of file qgsprocessingutils.cpp.

◆ invalidGeometryCheck()

Qgis::InvalidGeometryCheck QgsProcessingFeatureSource::invalidGeometryCheck ( ) const

Returns the geometry check method for the source.

See also: setInvalidGeometryCheck()

Since: QGIS 3.36

Definition at line 1971 of file qgsprocessingutils.cpp.

◆ maximumValue()

QVariant QgsProcessingFeatureSource::maximumValue ( int fieldIndex ) const

overridevirtual

Returns the maximum value for an attribute column or an invalid variant in case of error.

The base class implementation uses a non-optimised approach of looping through all features in the source.

See also: minimumValue(); uniqueValues()

Reimplemented from QgsFeatureSource.

Definition at line 1881 of file qgsprocessingutils.cpp.

◆ minimumValue()

QVariant QgsProcessingFeatureSource::minimumValue ( int fieldIndex ) const

overridevirtual

Returns the minimum value for an attribute column or an invalid variant in case of error.

The base class implementation uses a non-optimised approach of looping through all features in the source.

See also: maximumValue(); uniqueValues()

Reimplemented from QgsFeatureSource.

Definition at line 1853 of file qgsprocessingutils.cpp.

◆ setInvalidGeometryCheck()

void QgsProcessingFeatureSource::setInvalidGeometryCheck ( Qgis::InvalidGeometryCheck method )

Overrides the default geometry check method for the source.

See also: invalidGeometryCheck()

Since: QGIS 3.14

Definition at line 1951 of file qgsprocessingutils.cpp.

◆ sourceCrs()

QgsCoordinateReferenceSystem QgsProcessingFeatureSource::sourceCrs ( ) const

overridevirtual

Returns the coordinate reference system for features in the source.

Implements QgsFeatureSource.

Definition at line 1795 of file qgsprocessingutils.cpp.

◆ sourceExtent()

QgsRectangle QgsProcessingFeatureSource::sourceExtent ( ) const

overridevirtual

Returns the extent of all geometries from the source.

The base class implementation uses a non-optimised approach of looping through all features in the source.

Reimplemented from QgsFeatureSource.

Definition at line 1909 of file qgsprocessingutils.cpp.

◆ sourceName()

QString QgsProcessingFeatureSource::sourceName ( ) const

overridevirtual

Returns a friendly display name for the source.

The returned value can be an empty string.

Implements QgsFeatureSource.

Definition at line 1821 of file qgsprocessingutils.cpp.

◆ uniqueValues()

QSet< QVariant > QgsProcessingFeatureSource::uniqueValues	(	int	fieldIndex,
		int	limit = `-1`
	)		const

overridevirtual

Returns the set of unique values contained within the specified fieldIndex from this source.

If specified, the limit option can be used to limit the number of returned values. The base class implementation uses a non-optimised approach of looping through all features in the source.

See also: minimumValue(); maximumValue()

Reimplemented from QgsFeatureSource.

Definition at line 1826 of file qgsprocessingutils.cpp.

◆ wkbType()

Qgis::WkbType QgsProcessingFeatureSource::wkbType ( ) const

overridevirtual

Returns the geometry type for features returned by this source.

Implements QgsFeatureSource.

Definition at line 1805 of file qgsprocessingutils.cpp.

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

/home/fischer/src/qgis-3.38/src/core/processing/qgsprocessingutils.h
/home/fischer/src/qgis-3.38/src/core/processing/qgsprocessingutils.cpp

Public Member Functions

Detailed Description

Constructor & Destructor Documentation

◆ QgsProcessingFeatureSource()

◆ ~QgsProcessingFeatureSource()

Member Function Documentation

◆ allFeatureIds()

◆ createExpressionContextScope()

◆ featureCount()

◆ fields()

◆ getFeatures() [1/2]

◆ getFeatures() [2/2]

◆ hasFeatures()

◆ hasSpatialIndex()

◆ invalidGeometryCheck()

◆ maximumValue()

◆ minimumValue()

◆ setInvalidGeometryCheck()

◆ sourceCrs()

◆ sourceExtent()

◆ sourceName()

◆ uniqueValues()

◆ wkbType()