Uses another iterator as backend and writes features to the cache. More...

Inheritance diagram for QgsCachedFeatureWriterIterator:

Public Member Functions
	QgsCachedFeatureWriterIterator (QgsVectorLayerCache *vlCache, const QgsFeatureRequest &featureRequest)
	This constructor creates a feature iterator, which queries the backend and caches retrieved features.

bool	close () override
	Close this iterator.

bool	rewind () override
	Rewind to the beginning of the iterator.

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

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

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

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

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

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

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

Protected Member Functions
bool	fetchFeature (QgsFeature &f) override
	Implementation for fetching a feature.

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

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

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

virtual bool	nextFeatureFilterExpression (QgsFeature &f)
	By default, the iterator will fetch all features and check if the feature matches the expression.

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

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

void	ref ()
	Add reference.

RequestToSourceCrsResult	updateRequestToSourceCrs (QgsFeatureRequest &request, const QgsCoordinateTransform &transform) const
	Update a QgsFeatureRequest so that spatial filters are transformed to the source's coordinate reference system.

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

enum class	RequestToSourceCrsResult : int { Success , DistanceWithinMustBeCheckedManually }
	Possible results from the updateRequestToSourceCrs() method. More...

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

bool	mCompileFailed = false

CompileStatus	mCompileStatus = NoCompilation
	Status of compilation of filter expression.

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

QgsFeatureRequest	mRequest
	A copy of the feature request.

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

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

int	refs = 0
	reference counting (to allow seamless copying of QgsFeatureIterator instances)