A registry / canonical manager of data providers. More...

#include <qgsproviderregistry.h>

Classes
class	ProviderCandidateDetails
	Contains information pertaining to a candidate provider. More...

class	UnusableUriDetails
	Contains information about unusable URIs which aren't handled by any registered providers. More...

class	UnusableUriHandlerInterface
	An interface used to handle unusable URIs which aren't handled by any registered providers, and construct user-friendly warnings as to why the URI is unusable. More...

Public Types
typedef std::map< QString, QgsProviderMetadata * >	Providers
	Type for data provider metadata associative container. More...

enum	WidgetMode { None , Embedded , Manager }
	Different ways a source select dialog can be used. More...

Public Member Functions
	~QgsProviderRegistry ()

QString	absoluteToRelativeUri (const QString &providerKey, const QString &uri, const QgsReadWriteContext &context) const
	Converts absolute path(s) to relative path(s) in the given provider-specific URI. More...

bool	createDb (const QString &providerKey, const QString &dbPath, QString &errCause)
	Creates database by the provider on the path. More...

Qgis::VectorExportResult	createEmptyLayer (const QString &providerKey, const QString &uri, const QgsFields &fields, Qgis::WkbType wkbType, const QgsCoordinateReferenceSystem &srs, bool overwrite, QMap< int, int > &oldToNewAttrIdxMap, QString &errorMessage, const QMap< QString, QVariant > *options)
	Creates new empty vector layer. More...

QgsDataProvider *	createProvider (const QString &providerKey, const QString &dataSource, const QgsDataProvider::ProviderOptions &options=QgsDataProvider::ProviderOptions(), QgsDataProvider::ReadFlags flags=QgsDataProvider::ReadFlags())
	Creates a new instance of a provider. More...

Q_DECL_DEPRECATED QLibrary *	createProviderLibrary (const QString &providerKey) const
	Returns a new QLibrary for the specified providerKey. More...

QgsRasterDataProvider *	createRasterDataProvider (const QString &providerKey, const QString &uri, const QString &format, int nBands, Qgis::DataType type, int width, int height, double *geoTransform, const QgsCoordinateReferenceSystem &crs, const QStringList &createOptions=QStringList())
	Creates new instance of raster data provider. More...

Q_DECL_DEPRECATED QWidget *	createSelectionWidget (const QString &providerKey, QWidget *parent=nullptr, Qt::WindowFlags fl=Qt::WindowFlags(), QgsProviderRegistry::WidgetMode widgetMode=QgsProviderRegistry::WidgetMode::None)
	Returns a new widget for selecting layers from a provider. More...

QgsTransaction *	createTransaction (const QString &providerKey, const QString &connString)
	Returns new instance of transaction. More...

QString	databaseDrivers () const
	Returns a string containing the available database drivers. More...

QList< QgsDataItemProvider * >	dataItemProviders (const QString &providerKey) const
	Returns list of data item providers of the provider. More...

QVariantMap	decodeUri (const QString &providerKey, const QString &uri)
	Breaks a provider data source URI into its component paths (e.g. More...

bool	deleteStyleById (const QString &providerKey, const QString &uri, const QString &styleId, QString &errCause)
	Deletes a layer style defined by styleId. More...

QString	directoryDrivers () const
	Returns a string containing the available directory drivers. More...

QString	encodeUri (const QString &providerKey, const QVariantMap &parts)
	Reassembles a provider data source URI from its component paths (e.g. More...

QString	fileMeshDatasetFilters () const
	Returns a file filter string for supported mesh dataset files. More...

QString	fileMeshFilters () const
	Returns a file filter string for supported mesh files. More...

QString	filePointCloudFilters () const
	Returns a file filter string for supported point clouds. More...

QString	fileRasterFilters () const
	Returns a file filter string for supported raster files. More...

QString	fileVectorFilters () const
	Returns a file filter string for supported vector files. More...

QString	fileVectorTileFilters () const
	Returns a file filter string for supported vector tile files. More...

Q_DECL_DEPRECATED QFunctionPointer	function (const QString &providerKey, const QString &functionName) const
	Gets pointer to provider function. More...

QString	getStyleById (const QString &providerKey, const QString &uri, const QString &styleId, QString &errCause)
	Gets a layer style defined by styleId. More...

bool	handleUnusableUri (const QString &uri, UnusableUriDetails &details) const
	Returns `true` if the specified uri can potentially be handled by QGIS, if additional dependencies or build-time requirements are present. More...

Q_DECL_DEPRECATED QString	library (const QString &providerKey) const
	Returns path for the library of the provider. More...

QDir	libraryDirectory () const
	Returns the library directory where plugins are found. More...

int	listStyles (const QString &providerKey, const QString &uri, QStringList &ids, QStringList &names, QStringList &descriptions, QString &errCause)
	Lists stored layer styles in the provider defined by providerKey and uri. More...

QString	loadStoredStyle (const QString &providerKey, const QString &uri, QString &styleName, QString &errCause)
	Loads a layer style from the provider storage, reporting its name. More...

QString	loadStyle (const QString &providerKey, const QString &uri, QString &errCause)
	Loads a layer style defined by uri. More...

QString	pluginList (bool asHtml=false) const
	Returns list of provider plugins found. More...

QList< QgsProviderRegistry::ProviderCandidateDetails >	preferredProvidersForUri (const QString &uri) const
	Returns the details for the preferred provider(s) for opening the specified uri. More...

QString	protocolDrivers () const
	Returns a string containing the available protocol drivers. More...

Q_DECL_DEPRECATED int	providerCapabilities (const QString &providerKey) const
	Returns the provider capabilities. More...

QStringList	providerList () const
	Returns list of available providers by their keys. More...

QgsProviderMetadata *	providerMetadata (const QString &providerKey) const
	Returns metadata of the provider or `nullptr` if not found. More...

QSet< QString >	providersForLayerType (Qgis::LayerType type) const
	Returns a list of the provider keys for available providers which handle the specified layer type. More...

QList< QPair< QString, QString > >	pyramidResamplingMethods (const QString &providerKey)
	Returns list of raster pyramid resampling methods. More...

QList< QgsProviderSublayerDetails >	querySublayers (const QString &uri, Qgis::SublayerQueryFlags flags=Qgis::SublayerQueryFlags(), QgsFeedback *feedback=nullptr) const
	Queries the specified uri and returns a list of any valid sublayers found in the dataset which can be handled by any registered data provider. More...

Q_DECL_DEPRECATED void	registerGuis (QWidget *widget)

bool	registerProvider (QgsProviderMetadata *providerMetadata)
	register a new vector data provider from its providerMetadata More...

bool	registerUnusableUriHandler (UnusableUriHandlerInterface *handler)
	Registers an unusable URI handler, used to handle unusable URIs which aren't handled by any registered providers, and construct user-friendly warnings as to why the URI is unusable. More...

QString	relativeToAbsoluteUri (const QString &providerKey, const QString &uri, const QgsReadWriteContext &context) const
	Converts relative path(s) to absolute path(s) in the given provider-specific URI. More...

bool	saveLayerMetadata (const QString &providerKey, const QString &uri, const QgsLayerMetadata &metadata, QString &errorMessage) SIP_THROW(QgsNotSupportedException)
	Saves metadata to the layer corresponding to the specified uri. More...

bool	saveStyle (const QString &providerKey, const QString &uri, const QString &qmlStyle, const QString &sldStyle, const QString &styleName, const QString &styleDescription, const QString &uiFileContent, bool useAsDefault, QString &errCause)
	Saves a layer style to provider. More...

void	setLibraryDirectory (const QDir &path)
	Sets library directory where to search for plugins. More...

bool	shouldDeferUriForOtherProviders (const QString &uri, const QString &providerKey) const
	Returns `true` if the provider with matching providerKey should defer handling of the specified uri to another provider. More...

bool	styleExists (const QString &providerKey, const QString &uri, const QString &styleId, QString &errorCause)
	Returns `true` if a layer style with the specified styleId exists in the provider defined by providerKey and uri. More...

bool	uriIsBlocklisted (const QString &uri) const
	Returns `true` if the specified uri is known by any registered provider to be something which should be blocklisted from the QGIS interface, e.g. More...

Static Public Member Functions
static QgsProviderRegistry *	instance (const QString &pluginPath=QString())
	Means of accessing canonical single instance. More...

Friends
class	QgsApplication

Detailed Description

A registry / canonical manager of data providers.

This is a Singleton class that manages data provider access.

Providers can be either loaded via libraries or native providers that are included in the core QGIS installation and accessed through function pointers.

Loaded providers may be restricted using QGIS_PROVIDER_FILE environment variable. QGIS_PROVIDER_FILE is regexp pattern applied to provider file name (not provider key). For example, if the variable is set to gdal|ogr|postgres it will load only providers gdal, ogr and postgres.

Definition at line 60 of file qgsproviderregistry.h.

Member Typedef Documentation

◆ Providers

typedef std::map<QString, QgsProviderMetadata *> QgsProviderRegistry::Providers

Type for data provider metadata associative container.

Definition at line 730 of file qgsproviderregistry.h.

Member Enumeration Documentation

◆ WidgetMode

enum QgsProviderRegistry::WidgetMode

Different ways a source select dialog can be used.

Enumerator

None

Basic mode when the widget is used as a standalone dialog.

Originally used as GUI for individual "Add XXX layer" buttons in the main window. Likely not used in live code anymore.

Embedded

Used for the data source manager dialog where the widget is embedded as the main content for a particular tab.

Manager

Used by data items for QgsDataItem::paramWidget().

Originally used by QGIS Browser, but does not seem to be in live code anymore. The mode was meant to avoid some actions to keep the browser interface simple (supposedly).

Definition at line 70 of file qgsproviderregistry.h.

Constructor & Destructor Documentation

◆ ~QgsProviderRegistry()

QgsProviderRegistry::~QgsProviderRegistry ( )

Definition at line 496 of file qgsproviderregistry.cpp.

Member Function Documentation

◆ absoluteToRelativeUri()

QString QgsProviderRegistry::absoluteToRelativeUri	(	const QString &	providerKey,
		const QString &	uri,
		const QgsReadWriteContext &	context
	)		const

Converts absolute path(s) to relative path(s) in the given provider-specific URI.

and returns modified URI according to the context object's configuration. This is commonly used when writing project files. If a provider does not work with paths, unmodified URI will be returned.

Returns: modified URI with relative path(s)

Note: this function may not be supported by all providers. The default implementation uses QgsPathResolver::writePath() on the whole URI.

See also: relativeToAbsoluteUri()

Since: QGIS 3.30

Definition at line 619 of file qgsproviderregistry.cpp.

◆ createDb()

bool QgsProviderRegistry::createDb	(	const QString &	providerKey,
		const QString &	dbPath,
		QString &	errCause
	)

Creates database by the provider on the path.

Since: QGIS 3.10

Definition at line 798 of file qgsproviderregistry.cpp.

◆ createEmptyLayer()

Qgis::VectorExportResult QgsProviderRegistry::createEmptyLayer	(	const QString &	providerKey,
		const QString &	uri,
		const QgsFields &	fields,
		Qgis::WkbType	wkbType,
		const QgsCoordinateReferenceSystem &	srs,
		bool	overwrite,
		QMap< int, int > &	oldToNewAttrIdxMap,
		QString &	errorMessage,
		const QMap< QString, QVariant > *	options
	)

Creates new empty vector layer.

Note: not available in Python bindings

Since: QGIS 3.10

Definition at line 637 of file qgsproviderregistry.cpp.

◆ createProvider()

QgsDataProvider * QgsProviderRegistry::createProvider	(	const QString &	providerKey,
		const QString &	dataSource,
		const QgsDataProvider::ProviderOptions &	options = `QgsDataProvider::ProviderOptions()`,
		QgsDataProvider::ReadFlags	flags = `QgsDataProvider::ReadFlags()`
	)

Creates a new instance of a provider.

Parameters

providerKey	identifier of the provider
dataSource	string containing data source for the provider
options	provider options
flags	provider flags since QGIS 3.16

Returns: new instance of provider or nullptr on error

See also: createRasterDataProvider()

Definition at line 572 of file qgsproviderregistry.cpp.

◆ createProviderLibrary()

QLibrary * QgsProviderRegistry::createProviderLibrary ( const QString & providerKey ) const

Returns a new QLibrary for the specified providerKey.

Ownership of the returned object is transferred to the caller and the caller is responsible for deleting it.

If the provider uses direct provider function pointers instead of a library nullptr will be returned.

Deprecated:: QGIS 3.10 - providers may not need to be loaded from a library

Definition at line 854 of file qgsproviderregistry.cpp.

◆ createRasterDataProvider()

QgsRasterDataProvider * QgsProviderRegistry::createRasterDataProvider	(	const QString &	providerKey,
		const QString &	uri,
		const QString &	format,
		int	nBands,
		Qgis::DataType	type,
		int	width,
		int	height,
		double *	geoTransform,
		const QgsCoordinateReferenceSystem &	crs,
		const QStringList &	createOptions = `QStringList()`
	)

Creates new instance of raster data provider.

See also: createProvider()

Since: QGIS 3.10

Definition at line 656 of file qgsproviderregistry.cpp.

◆ createSelectionWidget()

QWidget * QgsProviderRegistry::createSelectionWidget	(	const QString &	providerKey,
		QWidget *	parent = `nullptr`,
		Qt::WindowFlags	fl = `Qt::WindowFlags()`,
		QgsProviderRegistry::WidgetMode	widgetMode = `QgsProviderRegistry::WidgetMode::None`
	)

Returns a new widget for selecting layers from a provider.

Either the parent widget must be set or the caller becomes responsible for deleting the returned widget.

Deprecated:: QGIS 3.10 - use QgsGui::sourceSelectProviderRegistry()->createDataSourceWidget() instead

Definition at line 819 of file qgsproviderregistry.cpp.

◆ createTransaction()

QgsTransaction * QgsProviderRegistry::createTransaction	(	const QString &	providerKey,
		const QString &	connString
	)

Returns new instance of transaction.

Ownership is transferred to the caller

Since: QGIS 3.10

Definition at line 810 of file qgsproviderregistry.cpp.

◆ databaseDrivers()

QString QgsProviderRegistry::databaseDrivers ( ) const

Returns a string containing the available database drivers.

Definition at line 930 of file qgsproviderregistry.cpp.

◆ dataItemProviders()

QList< QgsDataItemProvider * > QgsProviderRegistry::dataItemProviders ( const QString & providerKey ) const

Returns list of data item providers of the provider.

Note: Ownership of created data item providers is passed to the caller.

Since: QGIS 3.10

Definition at line 677 of file qgsproviderregistry.cpp.

◆ decodeUri()

QVariantMap QgsProviderRegistry::decodeUri	(	const QString &	providerKey,
		const QString &	uri
	)

Breaks a provider data source URI into its component paths (e.g.

file path, layer name).

Parameters

providerKey	identifier of the provider
uri	uri string

Returns: map containing components. Standard components include "path", "layerName", "url".

Note: this function may not be supported by all providers, an empty map will be returned in such case

Since: QGIS 3.4

Definition at line 601 of file qgsproviderregistry.cpp.

◆ deleteStyleById()

bool QgsProviderRegistry::deleteStyleById	(	const QString &	providerKey,
		const QString &	uri,
		const QString &	styleId,
		QString &	errCause
	)

Deletes a layer style defined by styleId.

Since: QGIS 3.10

Definition at line 731 of file qgsproviderregistry.cpp.

◆ directoryDrivers()

QString QgsProviderRegistry::directoryDrivers ( ) const

Returns a string containing the available directory drivers.

Definition at line 935 of file qgsproviderregistry.cpp.

◆ encodeUri()

QString QgsProviderRegistry::encodeUri	(	const QString &	providerKey,
		const QVariantMap &	parts
	)

Reassembles a provider data source URI from its component paths (e.g.

file path, layer name).

Parameters

providerKey	identifier of the provider
parts	parts as returned by decodeUri

Returns: datasource uri string

Note: this function may not be supported by all providers, an empty string will be returned in such case

See also: decodeUri()

Since: QGIS 3.12

Definition at line 610 of file qgsproviderregistry.cpp.

◆ fileMeshDatasetFilters()

QString QgsProviderRegistry::fileMeshDatasetFilters ( ) const

Returns a file filter string for supported mesh dataset files.

Returns a string suitable for a QFileDialog of mesh datasets file formats supported by all data providers.

See also: fileMeshFilters()

Since: QGIS 3.6

Definition at line 915 of file qgsproviderregistry.cpp.

◆ fileMeshFilters()

QString QgsProviderRegistry::fileMeshFilters ( ) const

Returns a file filter string for supported mesh files.

Returns a string suitable for a QFileDialog of mesh file formats supported by all data providers.

See also: fileMeshDatasetFilters(); fileRasterFilters(); fileVectorFilters(); filePointCloudFilters(); fileVectorTileFilters()

Since: QGIS 3.6

Definition at line 910 of file qgsproviderregistry.cpp.

◆ filePointCloudFilters()

QString QgsProviderRegistry::filePointCloudFilters ( ) const

Returns a file filter string for supported point clouds.

Returns a string suitable for a QFileDialog of point cloud file formats supported by all data providers.

See also: fileMeshFilters(); fileRasterFilters(); fileVectorFilters(); fileVectorTileFilters()

Since: QGIS 3.18

Definition at line 920 of file qgsproviderregistry.cpp.

◆ fileRasterFilters()

QString QgsProviderRegistry::fileRasterFilters ( ) const

Returns a file filter string for supported raster files.

Returns a string suitable for a QFileDialog of raster file formats supported by all data providers.

Note: This replaces QgsRasterLayer::buildSupportedRasterFileFilter()

See also: fileVectorFilters(); fileMeshFilters(); filePointCloudFilters(); fileVectorTileFilters()

Definition at line 905 of file qgsproviderregistry.cpp.

◆ fileVectorFilters()

QString QgsProviderRegistry::fileVectorFilters ( ) const

Returns a file filter string for supported vector files.

Returns a string suitable for a QFileDialog of vector file formats supported by all data providers.

See also: fileRasterFilters(); fileMeshFilters(); filePointCloudFilters(); fileVectorTileFilters()

Definition at line 900 of file qgsproviderregistry.cpp.

◆ fileVectorTileFilters()

QString QgsProviderRegistry::fileVectorTileFilters ( ) const

Returns a file filter string for supported vector tile files.

Returns a string suitable for a QFileDialog of vector tile file formats supported by all data providers.

See also: fileMeshFilters(); fileRasterFilters(); fileVectorFilters(); filePointCloudFilters()

Since: QGIS 3.32

Definition at line 925 of file qgsproviderregistry.cpp.

◆ function()

QFunctionPointer QgsProviderRegistry::function	(	const QString &	providerKey,
		const QString &	functionName
	)		const

Gets pointer to provider function.

Parameters

providerKey	identifier of the provider
functionName	name of function

Returns: pointer to function or nullptr on error. If the provider uses direct provider function pointers instead of a library nullptr will be returned.

Deprecated:: QGIS 3.10 - any provider functionality should be accessed through QgsProviderMetadata

Definition at line 830 of file qgsproviderregistry.cpp.

◆ getStyleById()

QString QgsProviderRegistry::getStyleById	(	const QString &	providerKey,
		const QString &	uri,
		const QString &	styleId,
		QString &	errCause
	)

Gets a layer style defined by styleId.

See also: styleExists()

Since: QGIS 3.10

Definition at line 716 of file qgsproviderregistry.cpp.

◆ handleUnusableUri()

bool QgsProviderRegistry::handleUnusableUri	(	const QString &	uri,
		UnusableUriDetails &	details
	)		const

Returns true if the specified uri can potentially be handled by QGIS, if additional dependencies or build-time requirements are present.

This can be used to show user-friendly warning messages advising them why a particular uri cannot be opened on their QGIS install. For example, if a QGIS install is built without the PDAL library then las/laz files are unusable, and this method can be used to retrieve a user-friendly warning as to why the las/laz files cannot be used on their QGIS build.

Warning: This method does not perform the test to actually determine if the given uri can be handled by any registered provider. It is assumed that prior to calling this method the caller has already determined in advance that the uri could not be handled.

Parameters

uri	URI to test
details	will be populated with details allowing construction of a user-friendly warning message

Returns: true if the uri was matched to a registered QgsProviderRegistry::UnusableUriHandlerInterface.

See also: registerUnusableUriHandler()

Since: QGIS 3.18.1

Definition at line 1003 of file qgsproviderregistry.cpp.

◆ instance()

QgsProviderRegistry * QgsProviderRegistry::instance ( const QString & pluginPath = QString() )

static

Means of accessing canonical single instance.

Definition at line 78 of file qgsproviderregistry.cpp.

◆ library()

QString QgsProviderRegistry::library ( const QString & providerKey ) const

Returns path for the library of the provider.

If the provider uses direct provider function pointers instead of a library an empty string will be returned.

Deprecated:: QGIS 3.10 - providers may not need to be loaded from a library (empty string returned)

Definition at line 505 of file qgsproviderregistry.cpp.

◆ libraryDirectory()

QDir QgsProviderRegistry::libraryDirectory ( ) const

Returns the library directory where plugins are found.

Definition at line 559 of file qgsproviderregistry.cpp.

◆ listStyles()

int QgsProviderRegistry::listStyles	(	const QString &	providerKey,
		const QString &	uri,
		QStringList &	ids,
		QStringList &	names,
		QStringList &	descriptions,
		QString &	errCause
	)

Lists stored layer styles in the provider defined by providerKey and uri.

Returns: -1 if not implemented by provider, otherwise number of styles stored

Since: QGIS 3.10

Definition at line 686 of file qgsproviderregistry.cpp.

◆ loadStoredStyle()

QString QgsProviderRegistry::loadStoredStyle	(	const QString &	providerKey,
		const QString &	uri,
		QString &	styleName,
		QString &	errCause
	)

Loads a layer style from the provider storage, reporting its name.

Parameters

providerKey	name of the data provider
uri	data source uri
styleName	the name of the style if available, empty otherwise
errCause	report errors

Returns: the style QML (XML)

Since: QGIS 3.30

Definition at line 774 of file qgsproviderregistry.cpp.

◆ loadStyle()

QString QgsProviderRegistry::loadStyle	(	const QString &	providerKey,
		const QString &	uri,
		QString &	errCause
	)

Loads a layer style defined by uri.

Returns: the style QML (XML)

Since: QGIS 3.10

Definition at line 761 of file qgsproviderregistry.cpp.

◆ pluginList()

QString QgsProviderRegistry::pluginList ( bool asHtml = false ) const

Returns list of provider plugins found.

Definition at line 519 of file qgsproviderregistry.cpp.

◆ preferredProvidersForUri()

QList< QgsProviderRegistry::ProviderCandidateDetails > QgsProviderRegistry::preferredProvidersForUri ( const QString & uri ) const

Returns the details for the preferred provider(s) for opening the specified uri.

The preferred provider is determined by comparing the priority returned by QgsProviderMetadata::priorityForUri() for all registered providers, and selecting the provider with the largest non-zero priority.

An empty list may be returned, which indicates that no providers are available which returned a non-zero priority for the specified URI.

In the case that multiple providers returned the same priority for the URI then all of these providers will be returned.

See also: shouldDeferUriForOtherProviders()

Since: QGIS 3.18

Definition at line 971 of file qgsproviderregistry.cpp.

◆ protocolDrivers()

QString QgsProviderRegistry::protocolDrivers ( ) const

Returns a string containing the available protocol drivers.

Definition at line 940 of file qgsproviderregistry.cpp.

◆ providerCapabilities()

int QgsProviderRegistry::providerCapabilities ( const QString & providerKey ) const

Returns the provider capabilities.

Parameters

providerKey identifier of the provider

Since: QGIS 2.6

Deprecated:: QGIS 3.10 (use instead capabilities() method of individual data item provider)

Definition at line 589 of file qgsproviderregistry.cpp.

◆ providerList()

QStringList QgsProviderRegistry::providerList ( ) const

Returns list of available providers by their keys.

Definition at line 945 of file qgsproviderregistry.cpp.

◆ providerMetadata()

QgsProviderMetadata * QgsProviderRegistry::providerMetadata ( const QString & providerKey ) const

Returns metadata of the provider or nullptr if not found.

Definition at line 955 of file qgsproviderregistry.cpp.

◆ providersForLayerType()

QSet< QString > QgsProviderRegistry::providersForLayerType ( Qgis::LayerType type ) const

Returns a list of the provider keys for available providers which handle the specified layer type.

Since: QGIS 3.26

Definition at line 960 of file qgsproviderregistry.cpp.

◆ pyramidResamplingMethods()

QList< QPair< QString, QString > > QgsProviderRegistry::pyramidResamplingMethods ( const QString & providerKey )

Returns list of raster pyramid resampling methods.

Since: QGIS 3.10

Definition at line 668 of file qgsproviderregistry.cpp.

◆ querySublayers()

QList< QgsProviderSublayerDetails > QgsProviderRegistry::querySublayers	(	const QString &	uri,
		Qgis::SublayerQueryFlags	flags = `Qgis::SublayerQueryFlags()`,
		QgsFeedback *	feedback = `nullptr`
	)		const

Queries the specified uri and returns a list of any valid sublayers found in the dataset which can be handled by any registered data provider.

This method iteratively queries each registered data provider and returns the complete collated list of all valid sublayers found in the dataset which can be opened by the data providers.

The optional flags argument can be used to control the behavior of the query.

The optional feedback argument can be used to provide cancellation support for long-running queries.

Since: QGIS 3.22

Definition at line 1040 of file qgsproviderregistry.cpp.

◆ registerGuis()

void QgsProviderRegistry::registerGuis ( QWidget * widget )

Deprecated:: since QGIS 3.10 - does nothing - use QgsGui::providerGuiRegistry()

Definition at line 874 of file qgsproviderregistry.cpp.

◆ registerProvider()

bool QgsProviderRegistry::registerProvider ( QgsProviderMetadata * providerMetadata )

register a new vector data provider from its providerMetadata

Returns: true on success, false if a provider with the same key was already registered

Note: ownership of the QgsProviderMetadata instance is transferred to the registry

Since: QGIS 3.2

Definition at line 879 of file qgsproviderregistry.cpp.

◆ registerUnusableUriHandler()

bool QgsProviderRegistry::registerUnusableUriHandler ( QgsProviderRegistry::UnusableUriHandlerInterface * handler )

Registers an unusable URI handler, used to handle unusable URIs which aren't handled by any registered providers, and construct user-friendly warnings as to why the URI is unusable.

Returns: true on success

Note: ownership of the UnusableUriHandlerInterface instance is transferred to the registry

Since: QGIS 3.18.1

Definition at line 997 of file qgsproviderregistry.cpp.

◆ relativeToAbsoluteUri()

QString QgsProviderRegistry::relativeToAbsoluteUri	(	const QString &	providerKey,
		const QString &	uri,
		const QgsReadWriteContext &	context
	)		const

Converts relative path(s) to absolute path(s) in the given provider-specific URI.

and returns modified URI according to the context object's configuration. This is commonly used when reading project files. If a provider does not work with paths, unmodified URI will be returned.

Returns: modified URI with absolute path(s)

Note: this function may not be supported by all providers. The default implementation uses QgsPathResolver::readPath() on the whole URI.

See also: absoluteToRelativeUri()

Since: QGIS 3.30

Definition at line 628 of file qgsproviderregistry.cpp.

◆ saveLayerMetadata()

bool QgsProviderRegistry::saveLayerMetadata	(	const QString &	providerKey,
		const QString &	uri,
		const QgsLayerMetadata &	metadata,
		QString &	errorMessage
	)

Saves metadata to the layer corresponding to the specified uri.

Parameters

providerKey	identifier of the provider
uri	uri of layer to store metadata for
metadata	layer metadata
errorMessage	descriptive string of error if encountered

Returns: true if the metadata was successfully saved.

Exceptions

QgsNotSupportedException if the provider does not support saving layer metadata for the specified uri.

Since: QGIS 3.20

Definition at line 787 of file qgsproviderregistry.cpp.

◆ saveStyle()

bool QgsProviderRegistry::saveStyle	(	const QString &	providerKey,
		const QString &	uri,
		const QString &	qmlStyle,
		const QString &	sldStyle,
		const QString &	styleName,
		const QString &	styleDescription,
		const QString &	uiFileContent,
		bool	useAsDefault,
		QString &	errCause
	)

Saves a layer style to provider.

Since: QGIS 3.10

Definition at line 745 of file qgsproviderregistry.cpp.

◆ setLibraryDirectory()

void QgsProviderRegistry::setLibraryDirectory ( const QDir & path )

Sets library directory where to search for plugins.

Definition at line 552 of file qgsproviderregistry.cpp.

◆ shouldDeferUriForOtherProviders()

bool QgsProviderRegistry::shouldDeferUriForOtherProviders	(	const QString &	uri,
		const QString &	providerKey
	)		const

Returns true if the provider with matching providerKey should defer handling of the specified uri to another provider.

This method tests whether any providers are listed as the preferred provider for uri (see preferredProvidersForUri()), and if so tests whether the specified provider is included in that preferred providers list. Returns true only if the specified provider is calculated as one of the preferred providers for the URI.

In the case that there is no registered preferred provider for the URI then false will be returned, and the provider must use another metric to determine whether it should handle the URI.

See also: preferredProvidersForUri()

Since: QGIS 3.18

Definition at line 1016 of file qgsproviderregistry.cpp.

◆ styleExists()

bool QgsProviderRegistry::styleExists	(	const QString &	providerKey,
		const QString &	uri,
		const QString &	styleId,
		QString &	errorCause
	)

Returns true if a layer style with the specified styleId exists in the provider defined by providerKey and uri.

Parameters

providerKey	provider key
uri	provider URI
styleId	style ID to test for
errorCause	will be set to a descriptive error message, if an error occurs while checking if the style exists

Returns: true if the layer style already exists

See also: getStyleById()

Since: QGIS 3.24

Definition at line 701 of file qgsproviderregistry.cpp.

◆ uriIsBlocklisted()

bool QgsProviderRegistry::uriIsBlocklisted ( const QString & uri ) const

Returns true if the specified uri is known by any registered provider to be something which should be blocklisted from the QGIS interface, e.g.

an internal detail only.

Specifically, this method can be utilized by the browser panel to hide noisy internal details for URIs which are known to be sidecar files only, such as ".aux.xml" files or ".shp.xml" files, or the "ept-build.json" files which sit alongside Entwine "ept.json" point cloud sources.

This method tests whether any of the registered providers return true for the their QgsProviderMetadata::uriIsBlocklisted() implementation for the specified URI.

Since: QGIS 3.18

Definition at line 1030 of file qgsproviderregistry.cpp.

Friends And Related Function Documentation

◆ QgsApplication

friend class QgsApplication

friend

Definition at line 815 of file qgsproviderregistry.h.

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

/build/qgis-3.32.0+99sid/src/core/providers/qgsproviderregistry.h
/build/qgis-3.32.0+99sid/src/core/providers/qgsproviderregistry.cpp

Classes

Public Types

Public Member Functions

Static Public Member Functions

Friends

Detailed Description

Member Typedef Documentation

◆ Providers

Member Enumeration Documentation

◆ WidgetMode

Constructor & Destructor Documentation

◆ ~QgsProviderRegistry()

Member Function Documentation

◆ absoluteToRelativeUri()

◆ createDb()

◆ createEmptyLayer()

◆ createProvider()

◆ createProviderLibrary()

◆ createRasterDataProvider()

◆ createSelectionWidget()

◆ createTransaction()

◆ databaseDrivers()

◆ dataItemProviders()

◆ decodeUri()

◆ deleteStyleById()

◆ directoryDrivers()

◆ encodeUri()

◆ fileMeshDatasetFilters()

◆ fileMeshFilters()

◆ filePointCloudFilters()

◆ fileRasterFilters()

◆ fileVectorFilters()

◆ fileVectorTileFilters()

◆ function()

◆ getStyleById()

◆ handleUnusableUri()

◆ instance()

◆ library()

◆ libraryDirectory()

◆ listStyles()

◆ loadStoredStyle()

◆ loadStyle()

◆ pluginList()

◆ preferredProvidersForUri()

◆ protocolDrivers()

◆ providerCapabilities()

◆ providerList()

◆ providerMetadata()

◆ providersForLayerType()

◆ pyramidResamplingMethods()

◆ querySublayers()

◆ registerGuis()

◆ registerProvider()

◆ registerUnusableUriHandler()

◆ relativeToAbsoluteUri()

◆ saveLayerMetadata()

◆ saveStyle()

◆ setLibraryDirectory()

◆ shouldDeferUriForOtherProviders()

◆ styleExists()

◆ uriIsBlocklisted()

Friends And Related Function Documentation

◆ QgsApplication