QgsVirtualLayerDefinition Class Reference

Class to manipulate the definition of a virtual layer. More...

#include <qgsvirtuallayerdefinition.h>

Classes
class	SourceLayer
	A SourceLayer is either a reference to a live layer in the registry or all the parameters needed to load it (provider key, source, etc.) More...

Public Types
typedef QList< QgsVirtualLayerDefinition::SourceLayer >	SourceLayers
	List of source layers.

Public Member Functions
	QgsVirtualLayerDefinition (const QString &filePath="")
	Constructor with an optional file path.
void	addSource (const QString &name, const QString &ref)
	Add a live layer source layer.
void	addSource (const QString &name, const QString &source, const QString &provider, const QString &encoding="")
	Add a layer with a source, a provider and an encoding.
QgsFields	fields () const
	Gets field definitions.
QString	filePath () const
	Gets the file path. May be empty.
QString	geometryField () const
	Gets the name of the geometry field. Empty if no geometry field.
long	geometrySrid () const
	Gets the SRID of the geometry.
Qgis::WkbType	geometryWkbType () const
	Gets the type of the geometry QgsWkbTypes::NoGeometry to hide any geometry QgsWkbTypes::Unknown for unknown types.
bool	hasDefinedGeometry () const
	Convenient method to test if the geometry is defined (not NoGeometry and not Unknown)
bool	hasReferencedLayers () const
	Convenience method to test whether the definition has referenced (live) layers.
bool	hasSourceLayer (const QString &name) const
	Convenience method to test if a given source layer is part of the definition.
bool	isLazy () const
	Returns the lazy mode.
QString	query () const
	Gets the SQL query.
void	setFields (const QgsFields &fields)
	Sets field definitions.
void	setFilePath (const QString &filePath)
	Sets the file path.
void	setGeometryField (const QString &geometryField)
	Sets the name of the geometry field.
void	setGeometrySrid (long srid)
	Sets the SRID of the geometry.
void	setGeometryWkbType (Qgis::WkbType t)
	Sets the type of the geometry.
void	setLazy (bool lazy)
	Sets the lazy mode.
void	setQuery (const QString &query)
	Sets the SQL query.
void	setSubsetString (const QString &subsetString)
	Sets the subsetString.
void	setUid (const QString &uid)
	Sets the name of the field with unique identifiers.
const QgsVirtualLayerDefinition::SourceLayers &	sourceLayers () const
	Gets access to the source layers.
QString	subsetString () const
	Returns the subset string.
QString	toString () const
	Convert into a QString that can be read by the virtual layer provider.
QUrl	toUrl () const
	Convert the definition into a QUrl.
QString	uid () const
	Gets the name of the field with unique identifiers.

Static Public Member Functions
static QgsVirtualLayerDefinition	fromUrl (const QUrl &url)
	Constructor to build a definition from a QUrl The path part of the URL is extracted as well as the following optional keys: layer_ref=layer_id[:name] represents a live layer referenced by its ID.

Detailed Description

Class to manipulate the definition of a virtual layer.

It is used to extract parameters from an initial virtual layer definition as well as to store the complete, expanded definition once types have been detected.

Definition at line 31 of file qgsvirtuallayerdefinition.h.

Member Typedef Documentation

SourceLayers

typedef QList<QgsVirtualLayerDefinition::SourceLayer> QgsVirtualLayerDefinition::SourceLayers

List of source layers.

Definition at line 115 of file qgsvirtuallayerdefinition.h.

Constructor & Destructor Documentation

QgsVirtualLayerDefinition()

QgsVirtualLayerDefinition::QgsVirtualLayerDefinition

(

const QString &

filePath = ""

)

Constructor with an optional file path.

Definition at line 26 of file qgsvirtuallayerdefinition.cpp.

Member Function Documentation

addSource() [1/2]

void QgsVirtualLayerDefinition::addSource	(	const QString &	name,
		const QString &	ref
	)

Add a live layer source layer.

Definition at line 252 of file qgsvirtuallayerdefinition.cpp.

addSource() [2/2]

void QgsVirtualLayerDefinition::addSource	(	const QString &	name,
		const QString &	source,
		const QString &	provider,
		const QString &	encoding = ""
	)

Add a layer with a source, a provider and an encoding.

Definition at line 257 of file qgsvirtuallayerdefinition.cpp.

fields()

QgsFields QgsVirtualLayerDefinition::fields ( ) const

inline

Gets field definitions.

Definition at line 173 of file qgsvirtuallayerdefinition.h.

filePath()

QString QgsVirtualLayerDefinition::filePath ( ) const

inline

Gets the file path. May be empty.

Definition at line 126 of file qgsvirtuallayerdefinition.h.

fromUrl()

QgsVirtualLayerDefinition QgsVirtualLayerDefinition::fromUrl ( const QUrl &  url )

static

Constructor to build a definition from a QUrl The path part of the URL is extracted as well as the following optional keys: layer_ref=layer_id[:name] represents a live layer referenced by its ID.

An optional name can be given layer=provider:source[:name[:encoding]] represents a layer given by its provider key, its source url (URL-encoded). An optional name and encoding can be given geometry=column_name[:type:srid] gives the definition of the geometry column. Type can be either a WKB type code or a string (point, linestring, etc.) srid is an integer uid=column_name is the name of a column with unique integer values. nogeometry is a flag to force the layer to be a non-geometry layer query=sql represents the SQL query. Must be URL-encoded field=column_name:[int|real|text] represents a field with its name and its type subsetstring=subset_string represents the subsetstring

Definition at line 31 of file qgsvirtuallayerdefinition.cpp.

geometryField()

QString QgsVirtualLayerDefinition::geometryField ( ) const

inline

Gets the name of the geometry field. Empty if no geometry field.

Definition at line 154 of file qgsvirtuallayerdefinition.h.

geometrySrid()

long QgsVirtualLayerDefinition::geometrySrid ( ) const

inline

Gets the SRID of the geometry.

Definition at line 168 of file qgsvirtuallayerdefinition.h.

geometryWkbType()

Qgis::WkbType QgsVirtualLayerDefinition::geometryWkbType ( ) const

inline

Gets the type of the geometry QgsWkbTypes::NoGeometry to hide any geometry QgsWkbTypes::Unknown for unknown types.

Definition at line 163 of file qgsvirtuallayerdefinition.h.

hasDefinedGeometry()

bool QgsVirtualLayerDefinition::hasDefinedGeometry ( ) const

inline

Convenient method to test if the geometry is defined (not NoGeometry and not Unknown)

Definition at line 184 of file qgsvirtuallayerdefinition.h.

hasReferencedLayers()

bool QgsVirtualLayerDefinition::hasReferencedLayers

(

)

const

Convenience method to test whether the definition has referenced (live) layers.

Definition at line 275 of file qgsvirtuallayerdefinition.cpp.

hasSourceLayer()

bool QgsVirtualLayerDefinition::hasSourceLayer

(

const QString &

name

)

const

Convenience method to test if a given source layer is part of the definition.

Definition at line 262 of file qgsvirtuallayerdefinition.cpp.

isLazy()

bool QgsVirtualLayerDefinition::isLazy ( ) const

inline

Returns the lazy mode.

Returns

true if the loading is delayed, false otherwise.

See also

setLazy()

Since

QGIS 3.2

Definition at line 151 of file qgsvirtuallayerdefinition.h.

query()

QString QgsVirtualLayerDefinition::query ( ) const

inline

Gets the SQL query.

Definition at line 121 of file qgsvirtuallayerdefinition.h.

setFields()

void QgsVirtualLayerDefinition::setFields ( const QgsFields &  fields )

inline

Sets field definitions.

Definition at line 175 of file qgsvirtuallayerdefinition.h.

setFilePath()

void QgsVirtualLayerDefinition::setFilePath ( const QString &  filePath )

inline

Sets the file path.

Definition at line 128 of file qgsvirtuallayerdefinition.h.

setGeometryField()

void QgsVirtualLayerDefinition::setGeometryField ( const QString &  geometryField )

inline

Sets the name of the geometry field.

Definition at line 156 of file qgsvirtuallayerdefinition.h.

setGeometrySrid()

void QgsVirtualLayerDefinition::setGeometrySrid ( long  srid )

inline

Sets the SRID of the geometry.

Definition at line 170 of file qgsvirtuallayerdefinition.h.

setGeometryWkbType()

void QgsVirtualLayerDefinition::setGeometryWkbType ( Qgis::WkbType  t )

inline

Sets the type of the geometry.

Definition at line 165 of file qgsvirtuallayerdefinition.h.

setLazy()

void QgsVirtualLayerDefinition::setLazy ( bool  lazy )

inline

Sets the lazy mode.

If lazy is true, then the loading is delayed until an explicit reloading of the layer.

Parameters

lazy	true to delay the loading, false otherwise

See also

QgsDataProvider::reloadData()

isLazy()

Since

QGIS 3.2

Definition at line 143 of file qgsvirtuallayerdefinition.h.

setQuery()

void QgsVirtualLayerDefinition::setQuery ( const QString &  query )

inline

Sets the SQL query.

Definition at line 123 of file qgsvirtuallayerdefinition.h.

setSubsetString()

void QgsVirtualLayerDefinition::setSubsetString

(

const QString &

subsetString

)

Sets the subsetString.

Since

QGIS 3.16

Definition at line 293 of file qgsvirtuallayerdefinition.cpp.

setUid()

void QgsVirtualLayerDefinition::setUid ( const QString &  uid )

inline

Sets the name of the field with unique identifiers.

Definition at line 133 of file qgsvirtuallayerdefinition.h.

sourceLayers()

const QgsVirtualLayerDefinition::SourceLayers & QgsVirtualLayerDefinition::sourceLayers ( ) const

inline

Gets access to the source layers.

Definition at line 118 of file qgsvirtuallayerdefinition.h.

subsetString()

QString QgsVirtualLayerDefinition::subsetString

(

)

const

Returns the subset string.

Since

QGIS 3.16

Definition at line 288 of file qgsvirtuallayerdefinition.cpp.

toString()

QString QgsVirtualLayerDefinition::toString

(

)

const

Convert into a QString that can be read by the virtual layer provider.

Definition at line 247 of file qgsvirtuallayerdefinition.cpp.

toUrl()

QUrl QgsVirtualLayerDefinition::toUrl

(

)

const

Convert the definition into a QUrl.

Definition at line 176 of file qgsvirtuallayerdefinition.cpp.

uid()

QString QgsVirtualLayerDefinition::uid ( ) const

inline

Gets the name of the field with unique identifiers.

Definition at line 131 of file qgsvirtuallayerdefinition.h.

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

• /build/qgis-3.34.0+99sid/src/core/qgsvirtuallayerdefinition.h
• /build/qgis-3.34.0+99sid/src/core/qgsvirtuallayerdefinition.cpp