#include <qgsvectorlayerfeatureiterator.h>

Inheritance diagram for QgsVectorLayerFeatureIterator:

Classes
struct	FetchJoinInfo
	Join information prepared for fast attribute id mapping in QgsVectorLayerJoinBuffer::updateFeatureAttributes(). More...

Public Member Functions
	QgsVectorLayerFeatureIterator (QgsVectorLayerFeatureSource *source, bool ownSource, const QgsFeatureRequest &request)

	~QgsVectorLayerFeatureIterator () override

bool	close () override
	end of iterating: free the resources / lock More...

bool	isValid () const override
	Returns if this iterator is valid. More...

bool	rewind () override
	reset the iterator to the starting position More...

void	setInterruptionChecker (QgsFeedback *interruptionChecker) override
	Attach an object that can be queried regularly by the iterator to check if it must stopped. More...

Public Member Functions inherited from QgsAbstractFeatureIteratorFromSource< QgsVectorLayerFeatureSource >
	QgsAbstractFeatureIteratorFromSource (QgsVectorLayerFeatureSource *source, bool ownSource, const QgsFeatureRequest &request)

	~QgsAbstractFeatureIteratorFromSource () override

Public Member Functions inherited from QgsAbstractFeatureIterator
	QgsAbstractFeatureIterator (const QgsFeatureRequest &request)
	base class constructor - stores the iteration parameters More...

virtual	~QgsAbstractFeatureIterator ()=default
	destructor makes sure that the iterator is closed properly More...

bool	compileFailed () const
	Indicator if there was an error when sending the compiled query to the server. More...

CompileStatus	compileStatus () const
	Returns the status of expression compilation for filter expression requests. More...

virtual bool	nextFeature (QgsFeature &f)
	fetch next feature, return true on success More...

Protected Member Functions
void	addExpressionAttribute (QgsFeature &f, int attrIndex)
	Adds an expression based attribute to a feature. More...

void	addJoinedAttributes (QgsFeature &f)

void	addVirtualAttributes (QgsFeature &f)
	Adds attributes that don't source from the provider but are added inside QGIS Includes. More...

bool	fetchFeature (QgsFeature &feature) override
	fetch next feature, return true on success More...

bool	fetchNextAddedFeature (QgsFeature &f)

bool	fetchNextChangedAttributeFeature (QgsFeature &f)

bool	fetchNextChangedGeomFeature (QgsFeature &f)

bool	nextFeatureFid (QgsFeature &f)

bool	nextFeatureFilterExpression (QgsFeature &f) override
	Overrides default method as we only need to filter features in the edit buffer while for others filtering is left to the provider implementation. More...

void	prepareExpression (int fieldIdx)

void	prepareField (int fieldIdx)

void	prepareFields ()

void	prepareJoin (int fieldIdx)

bool	prepareSimplification (const QgsSimplifyMethod &simplifyMethod) override
	Setup the simplification of geometries to fetch using the specified simplify method. More...

void	rewindEditBuffer ()

void	updateChangedAttributes (QgsFeature &f)
	Update feature with uncommitted attribute updates. More...

void	updateFeatureGeometry (QgsFeature &f)
	Update feature with uncommitted geometry updates. More...

void	useAddedFeature (const QgsFeature &src, QgsFeature &f)

void	useChangedAttributeFeature (QgsFeatureId fid, const QgsGeometry &geom, QgsFeature &f)

Protected Member Functions inherited from QgsAbstractFeatureIteratorFromSource< QgsVectorLayerFeatureSource >
void	iteratorClosed ()
	to be called by from subclass in close() More...

Protected Member Functions inherited from QgsAbstractFeatureIterator
void	deref ()
	Remove reference, delete if refs == 0. More...

QgsRectangle	filterRectToSourceCrs (const QgsCoordinateTransform &transform) const SIP_THROW(QgsCsException)
	Returns a rectangle representing the original request's QgsFeatureRequest::filterRect(). More...

void	geometryToDestinationCrs (QgsFeature &feature, const QgsCoordinateTransform &transform) const
	Transforms feature's geometry according to the specified coordinate transform. More...

virtual bool	nextFeatureFilterFids (QgsFeature &f)
	By default, the iterator will fetch all features and check if the id is in the request. More...

void	ref ()
	Add reference. More...

Protected Attributes
QgsFeatureIterator	mChangedFeaturesIterator

QgsFeatureRequest	mChangedFeaturesRequest

QMap< int, QgsExpression * >	mExpressionFieldInfo

QgsFeatureMap::ConstIterator	mFetchAddedFeaturesIt

QgsGeometryMap::ConstIterator	mFetchChangedGeomIt

QSet< QgsFeatureId >	mFetchConsidered

bool	mFetchedFid

QMap< const QgsVectorLayerJoinInfo *, QgsVectorLayerFeatureIterator::FetchJoinInfo >	mFetchJoinInfo
	Information about joins used in the current select() statement. More...

QgsRectangle	mFilterRect

bool	mHasVirtualAttributes

QgsFeatureIterator	mProviderIterator

QgsFeatureRequest	mProviderRequest

QgsCoordinateTransform	mTransform

Protected Attributes inherited from QgsAbstractFeatureIteratorFromSource< QgsVectorLayerFeatureSource >
bool	mOwnSource

QgsVectorLayerFeatureSource *	mSource

Protected Attributes inherited from QgsAbstractFeatureIterator
bool	mClosed = false
	Sets to true, as soon as the iterator is closed. More...

bool	mCompileFailed = false

CompileStatus	mCompileStatus = NoCompilation
	Status of compilation of filter expression. More...

long	mFetchedCount = 0
	Number of features already fetched by iterator. More...

QgsFeatureRequest	mRequest
	A copy of the feature request. More...

bool	mValid = true
	An invalid state of a feature iterator indicates that there was a problem with even getting it up and running. More...

bool	mZombie = false
	A feature iterator may be closed already but still be serving features from the cache. More...

int	refs = 0
	reference counting (to allow seamless copying of QgsFeatureIterator instances) TODO QGIS3: make this private More...

Additional Inherited Members
Public Types inherited from QgsAbstractFeatureIterator
enum	CompileStatus { NoCompilation, PartiallyCompiled, Compiled }
	Status of expression compilation for filter expression requests. More...

Detailed Description

Definition at line 120 of file qgsvectorlayerfeatureiterator.h.

Constructor & Destructor Documentation

QgsVectorLayerFeatureIterator::QgsVectorLayerFeatureIterator	(	QgsVectorLayerFeatureSource *	source,
		bool	ownSource,
		const QgsFeatureRequest &	request
	)

Definition at line 117 of file qgsvectorlayerfeatureiterator.cpp.

QgsVectorLayerFeatureIterator::~QgsVectorLayerFeatureIterator ( )

override

Definition at line 279 of file qgsvectorlayerfeatureiterator.cpp.

Member Function Documentation

void QgsVectorLayerFeatureIterator::addExpressionAttribute	(	QgsFeature &	f,
		int	attrIndex
	)

protected

Adds an expression based attribute to a feature.

Parameters

f	feature
attrIndex	attribute index

Note: not available in Python bindings

Since: QGIS 2.14

Definition at line 883 of file qgsvectorlayerfeatureiterator.cpp.

void QgsVectorLayerFeatureIterator::addJoinedAttributes ( QgsFeature & f )

protected

Note: not available in Python bindings

Definition at line 826 of file qgsvectorlayerfeatureiterator.cpp.

void QgsVectorLayerFeatureIterator::addVirtualAttributes ( QgsFeature & f )

protected

Adds attributes that don't source from the provider but are added inside QGIS Includes.

Joined fields
Expression fields

Parameters

f	The feature will be modified

Note: not available in Python bindings

Definition at line 843 of file qgsvectorlayerfeatureiterator.cpp.

bool QgsVectorLayerFeatureIterator::close ( )

overridevirtual

end of iterating: free the resources / lock

Implements QgsAbstractFeatureIterator.

Definition at line 405 of file qgsvectorlayerfeatureiterator.cpp.

bool QgsVectorLayerFeatureIterator::fetchFeature ( QgsFeature & feature )

overrideprotectedvirtual

fetch next feature, return true on success

Implements QgsAbstractFeatureIterator.

Definition at line 288 of file qgsvectorlayerfeatureiterator.cpp.

bool QgsVectorLayerFeatureIterator::fetchNextAddedFeature ( QgsFeature & f )

protected

Note: not available in Python bindings

Definition at line 429 of file qgsvectorlayerfeatureiterator.cpp.

bool QgsVectorLayerFeatureIterator::fetchNextChangedAttributeFeature ( QgsFeature & f )

protected

Note: not available in Python bindings

Definition at line 512 of file qgsvectorlayerfeatureiterator.cpp.

bool QgsVectorLayerFeatureIterator::fetchNextChangedGeomFeature ( QgsFeature & f )

protected

Note: not available in Python bindings

Definition at line 473 of file qgsvectorlayerfeatureiterator.cpp.

bool QgsVectorLayerFeatureIterator::isValid ( ) const

overridevirtual

Returns if this iterator is valid.

An invalid feature iterator is not able to provide a reliable source for data. If an iterator is invalid, either give up or try to send the request again (preferably after a timeout to give the system some time to stay responsive).

If you want to check if the iterator successfully completed, better use QgsFeatureIterator::isClosed().

Since: QGIS 3.0

Reimplemented from QgsAbstractFeatureIterator.

Definition at line 424 of file qgsvectorlayerfeatureiterator.cpp.

bool QgsVectorLayerFeatureIterator::nextFeatureFid ( QgsFeature & f )

protected

Note: not available in Python bindings

Definition at line 1011 of file qgsvectorlayerfeatureiterator.cpp.

bool QgsVectorLayerFeatureIterator::nextFeatureFilterExpression ( QgsFeature & f )

inlineoverrideprotectedvirtual

Overrides default method as we only need to filter features in the edit buffer while for others filtering is left to the provider implementation.

Reimplemented from QgsAbstractFeatureIterator.

Definition at line 163 of file qgsvectorlayerfeatureiterator.h.

void QgsVectorLayerFeatureIterator::prepareExpression ( int fieldIdx )

protected

Note: not available in Python bindings

Definition at line 623 of file qgsvectorlayerfeatureiterator.cpp.

void QgsVectorLayerFeatureIterator::prepareField ( int fieldIdx )

protected

Note: not available in Python bindings

Definition at line 804 of file qgsvectorlayerfeatureiterator.cpp.

void QgsVectorLayerFeatureIterator::prepareFields ( )

protected

Note: not available in Python bindings

Definition at line 667 of file qgsvectorlayerfeatureiterator.cpp.

void QgsVectorLayerFeatureIterator::prepareJoin ( int fieldIdx )

protected

Note: not available in Python bindings

Definition at line 584 of file qgsvectorlayerfeatureiterator.cpp.

bool QgsVectorLayerFeatureIterator::prepareSimplification ( const QgsSimplifyMethod & simplifyMethod )

overrideprotectedvirtual

Setup the simplification of geometries to fetch using the specified simplify method.

Reimplemented from QgsAbstractFeatureIterator.

Definition at line 899 of file qgsvectorlayerfeatureiterator.cpp.

bool QgsVectorLayerFeatureIterator::rewind ( )

overridevirtual

reset the iterator to the starting position

Implements QgsAbstractFeatureIterator.

Definition at line 387 of file qgsvectorlayerfeatureiterator.cpp.

void QgsVectorLayerFeatureIterator::rewindEditBuffer ( )

protected

Note: not available in Python bindings

Definition at line 576 of file qgsvectorlayerfeatureiterator.cpp.

void QgsVectorLayerFeatureIterator::setInterruptionChecker ( QgsFeedback * interruptionChecker )

overridevirtual

Attach an object that can be queried regularly by the iterator to check if it must stopped.

This is mostly useful for iterators where a single nextFeature()/fetchFeature() iteration might be very long. A typical use case is the WFS provider. When nextFeature()/fetchFeature() is reasonably fast, it is not necessary to implement this method. The default implementation does nothing.