QgsProject Class Reference

Encapsulates a QGIS project, including sets of map layers and their styles, layouts, annotations, canvases, etc. More...

#include <qgsproject.h>

Inheritance diagram for QgsProject:

Public Types
enum class	DataDefinedServerProperty : int { NoProperty = 0 , AllProperties = 1 , WMSOnlineResource = 2 }
	Data defined properties. More...

Public Slots
bool	commitChanges (QStringList &commitErrors, bool stopEditing=true, QgsVectorLayer *vectorLayer=nullptr)
	Attempts to commit to the underlying data provider any buffered changes made since the last to call to startEditing().
QgsPropertyCollection	dataDefinedServerProperties () const
	Returns the data defined properties used for overrides in user defined server parameters.
void	registerTranslatableContainers (QgsTranslationContext *translationContext, QgsAttributeEditorContainer *parent, const QString &layerId)
	Registers the containers that require translation into the translationContext.
void	registerTranslatableObjects (QgsTranslationContext *translationContext)
	Registers the objects that require translation into the translationContext.
bool	rollBack (QStringList &rollbackErrors, bool stopEditing=true, QgsVectorLayer *vectorLayer=nullptr)
	Stops a current editing operation on vectorLayer and discards any uncommitted edits.
void	setDataDefinedServerProperties (const QgsPropertyCollection &properties)
	Sets the data defined properties used for overrides in user defined server parameters to properties.
void	setDirty (bool b=true)
	Flag the project as dirty (modified).
void	setPresetHomePath (const QString &path)
	Sets the project's home path.
void	setSnappingConfig (const QgsSnappingConfig &snappingConfig)
	The snapping configuration for this project.
bool	startEditing (QgsVectorLayer *vectorLayer=nullptr)
	Makes the layer editable.

Signals
void	aboutToBeCleared ()
	Emitted when the project is about to be cleared.
void	areaUnitsChanged ()
	Emitted when the default area units changes.
void	avoidIntersectionsLayersChanged ()
	Emitted whenever avoidIntersectionsLayers has changed.
void	avoidIntersectionsModeChanged ()
	Emitted whenever the avoid intersections mode has changed.
void	backgroundColorChanged ()
	Emitted whenever the project's canvas background color has been changed.
void	cleared ()
	Emitted when the project is cleared (and additionally when an open project is cleared just before a new project is read).
void	crs3DChanged ()
	Emitted when the crs3D() of the project has changed.
void	crsChanged ()
	Emitted when the crs() of the project has changed.
void	customVariablesChanged ()
	Emitted whenever the expression variables stored in the project have been changed.
void	dirtySet ()
	Emitted when setDirty(true) is called.
void	distanceUnitsChanged ()
	Emitted when the default distance units changes.
void	elevationShadingRendererChanged ()
	Emitted when the map shading renderer changes.
void	ellipsoidChanged (const QString &ellipsoid)
	Emitted when the project ellipsoid is changed.
void	fileNameChanged ()
	Emitted when the file name of the project changes.
void	homePathChanged ()
	Emitted when the home path of the project changes.
void	isDirtyChanged (bool dirty)
	Emitted when the project dirty status changes.
void	labelingEngineSettingsChanged ()
	Emitted when global configuration of the labeling engine changes.
void	layerLoaded (int i, int n)
	Emitted when a layer from a projects was read.
void	layerRemoved (const QString &layerId)
	Emitted after a layer was removed from the registry.
void	layersAdded (const QList< QgsMapLayer * > &layers)
	Emitted when one or more layers were added to the registry.
void	layersRemoved (const QStringList &layerIds)
	Emitted after one or more layers were removed from the registry.
void	layersWillBeRemoved (const QList< QgsMapLayer * > &layers)
	Emitted when one or more layers are about to be removed from the registry.
void	layersWillBeRemoved (const QStringList &layerIds)
	Emitted when one or more layers are about to be removed from the registry.
void	layerWasAdded (QgsMapLayer *layer)
	Emitted when a layer was added to the registry.
void	layerWillBeRemoved (const QString &layerId)
	Emitted when a layer is about to be removed from the registry.
void	layerWillBeRemoved (QgsMapLayer *layer)
	Emitted when a layer is about to be removed from the registry.
void	legendLayersAdded (const QList< QgsMapLayer * > &layers)
	Emitted, when a layer was added to the registry and the legend.
void	loadingLayer (const QString &layerName)
	Emitted when a layer is loaded.
void	loadingLayerMessageReceived (const QString &layerName, const QList< QgsReadWriteContext::ReadWriteMessage > &messages)
	Emitted when loading layers has produced some messages.
Q_DECL_DEPRECATED void	mapScalesChanged ()
	Emitted when the list of custom project map scales changes.
void	mapThemeCollectionChanged ()
	Emitted when the map theme collection changes.
void	metadataChanged ()
	Emitted when the project's metadata is changed.
void	missingDatumTransforms (const QStringList &missingTransforms)
	Emitted when datum transforms stored in the project are not available locally.
Q_DECL_DEPRECATED void	nonIdentifiableLayersChanged (QStringList nonIdentifiableLayers)
	Emitted when the list of layer which are excluded from map identification changes.
Q_DECL_DEPRECATED void	oldProjectVersionWarning (const QString &warning)
	Emitted when an old project file is read.
void	projectColorsChanged ()
	Emitted whenever the project's color scheme has been changed.
void	projectSaved ()
	Emitted when the project file has been written and closed.
void	readMapLayer (QgsMapLayer *mapLayer, const QDomElement &layerNode)
	Emitted after the basic initialization of a layer from the project file is done.
void	readProject (const QDomDocument &document)
	Emitted when a project is being read.
void	readProjectWithContext (const QDomDocument &document, QgsReadWriteContext &context)
	Emitted when a project is being read.
void	readVersionMismatchOccurred (const QString &fileVersion)
	Emitted when a project is read and the version of QGIS used to save the project differs from the current QGIS version.
void	removeAll ()
	Emitted when all layers are removed, before layersWillBeRemoved() and layerWillBeRemoved() signals are emitted.
void	selectionColorChanged ()
	Emitted whenever the project's selection color has been changed.
void	snappingConfigChanged (const QgsSnappingConfig &config)
	Emitted whenever the configuration for snapping has changed.
void	topologicalEditingChanged ()
	Emitted when the topological editing flag has changed.
void	transactionGroupsChanged ()
	Emitted whenever a new transaction group has been created or a transaction group has been removed.
void	transactionModeChanged ()
	Emitted when the transaction mode has changed.
void	transformContextChanged ()
	Emitted when the project transformContext() is changed.
void	verticalCrsChanged ()
	Emitted when the verticalCrs() of the project has changed.
void	writeMapLayer (QgsMapLayer *mapLayer, QDomElement &layerElem, QDomDocument &doc)
	Emitted when a layer is being saved.
void	writeProject (QDomDocument &document)
	Emitted when the project is being written.

Public Member Functions
	QgsProject (QObject *parent=nullptr, Qgis::ProjectCapabilities capabilities=Qgis::ProjectCapability::ProjectStyles)
	Create a new QgsProject.
	~QgsProject () override
QString	absoluteFilePath () const
	Returns full absolute path to the project file if the project is stored in a file system - derived from fileName().
QString	absolutePath () const
	Returns full absolute path to the project folder if the project is stored in a file system - derived from fileName().
bool	accept (QgsStyleEntityVisitorInterface *visitor) const
	Accepts the specified style entity visitor, causing it to visit all style entities associated with the project.
QgsMapLayer *	addMapLayer (QgsMapLayer *mapLayer, bool addToLegend=true, bool takeOwnership=true)
	Add a layer to the map of loaded layers.
QList< QgsMapLayer * >	addMapLayers (const QList< QgsMapLayer * > &mapLayers, bool addToLegend=true, bool takeOwnership=true)
	Add a list of layers to the map of loaded layers.
QgsAnnotationManager *	annotationManager ()
	Returns pointer to the project's annotation manager.
const QgsAnnotationManager *	annotationManager () const
	Returns a const pointer to the project's annotation manager.
Qgis::AreaUnit	areaUnits () const
	Convenience function to query default area measurement units for project.
QStringList	attachedFiles () const
	Returns a map of all attached files with identifier and real paths.
QString	attachmentIdentifier (const QString &attachedFile) const
	Returns an identifier for an attachment file path An attachment identifier is a string which does not depend on the project archive storage location.
Q_DECL_DEPRECATED bool	autoTransaction () const
	Transactional editing means that on supported datasources (postgres databases) the edit state of all tables that originate from the same database are synchronized and executed in a server side transaction.
QgsAuxiliaryStorage *	auxiliaryStorage ()
	Returns the current auxiliary storage.
const QgsAuxiliaryStorage *	auxiliaryStorage () const
	Returns the current const auxiliary storage.
QList< QgsVectorLayer * >	avoidIntersectionsLayers () const
	A list of layers with which intersections should be avoided.
Qgis::AvoidIntersectionsMode	avoidIntersectionsMode () const
	Returns the current avoid intersections mode.
QColor	backgroundColor () const
	Returns the default background color used by default map canvases.
QString	baseName () const
	Returns the base name of the project file without the path and without extension - derived from fileName().
QgsBookmarkManager *	bookmarkManager ()
	Returns the project's bookmark manager, which manages bookmarks within the project.
const QgsBookmarkManager *	bookmarkManager () const
	Returns the project's bookmark manager, which manages bookmarks within the project.
Qgis::ProjectCapabilities	capabilities () const
	Returns the project's capabilities, which dictate optional functionality which can be selectively enabled for a QgsProject object.
void	cleanFunctionsFromProject ()
	Unloads python expression functions stored in the current project and reloads local functions from the user profile.
void	clear ()
	Clears the project, removing all settings and resetting it back to an empty, default state.
int	count () const
	Returns the number of registered layers.
QString	createAttachedFile (const QString &nameTemplate)
	Attaches a file to the project.
QgsLayerTreeGroup *	createEmbeddedGroup (const QString &groupName, const QString &projectFilePath, const QStringList &invisibleLayers, Qgis::ProjectReadFlags flags=Qgis::ProjectReadFlags())
	Create layer group instance defined in an arbitrary project file.
bool	createEmbeddedLayer (const QString &layerId, const QString &projectFilePath, QList< QDomNode > &brokenNodes, bool saveFlag=true, Qgis::ProjectReadFlags flags=Qgis::ProjectReadFlags())
	Creates a maplayer instance defined in an arbitrary project file.
QgsExpressionContext	createExpressionContext () const override
	This method needs to be reimplemented in all classes which implement this interface and return an expression context.
QgsExpressionContextScope *	createExpressionContextScope () const override
	This method needs to be reimplemented in all classes which implement this interface and return an expression context scope.
QgsCoordinateReferenceSystem	crs () const
	Returns the project's native coordinate reference system.
QgsCoordinateReferenceSystem	crs3D () const
	Returns the CRS to use for the project when transforming 3D data, or when z/elevation value handling is important.
QVariantMap	customVariables () const
	A map of custom project variables.
QgsCoordinateReferenceSystem	defaultCrsForNewLayers () const
	Returns the default CRS for new layers based on the settings and the current project CRS.
QgsProjectDisplaySettings *	displaySettings ()
	Returns the project's display settings, which contains settings and properties relating to how a QgsProject should display values such as map coordinates and bearings.
const QgsProjectDisplaySettings *	displaySettings () const
	Returns the project's display settings, which contains settings and properties relating to how a QgsProject should display values such as map coordinates and bearings.
Qgis::DistanceUnit	distanceUnits () const
	Convenience function to query default distance measurement units for project.
void	dumpProperties () const
	Dump out current project properties to stderr.
QgsVectorLayerEditBufferGroup *	editBufferGroup ()
	Returns the edit buffer group.
QgsProjectElevationProperties *	elevationProperties ()
	Returns the project's elevation properties, which contains the project's elevation related settings.
const QgsProjectElevationProperties *	elevationProperties () const
	Returns the project's elevation properties, which contains the project's elevation related settings.
QgsElevationShadingRenderer	elevationShadingRenderer () const
	Returns the elevation shading renderer used for map shading.
QString	ellipsoid () const
	Returns a proj string representing the project's ellipsoid setting, e.g., "WGS84".
QStringList	entryList (const QString &scope, const QString &key) const
	Returns a list of child keys with values which exist within the the specified scope and key.
QString	error () const
	Returns error message from previous read/write.
Q_DECL_DEPRECATED bool	evaluateDefaultValues () const
	Should default values be evaluated on provider side when requested and not when committed.
Q_DECL_DEPRECATED QFileInfo	fileInfo () const
	Returns QFileInfo object for the project's associated file.
QString	fileName () const
	Returns the project's file name.
Qgis::FilePathType	filePathStorage () const
	Returns the type of paths used when storing file paths in a QGS/QGZ project file.
Qgis::ProjectFlags	flags () const
	Returns the project's flags, which dictate the behavior of the project.
void	generateTsFile (const QString &locale)
	Triggers the collection strings of .qgs to be included in ts file and calls writeTsFile()
QgsProjectGpsSettings *	gpsSettings ()
	Returns the project's GPS settings, which contains settings and properties relating to how a QgsProject should interact with a GPS device.
const QgsProjectGpsSettings *	gpsSettings () const
	Returns the project's GPS settings, which contains settings and properties relating to how a QgsProject should interact with a GPS device.
QString	homePath () const
	Returns the project's home path.
bool	isDirty () const
	Returns true if the project has been modified since the last write()
bool	isZipped () const
	Returns true if the project comes from a zip archive, false otherwise.
const QgsLabelingEngineSettings &	labelingEngineSettings () const
	Returns project's global labeling engine settings.
QDateTime	lastModified () const
	Returns last modified time of the project file as returned by the file system (or other project storage).
QDateTime	lastSaveDateTime () const
	Returns the date and time when the project was last saved.
QgsProjectVersion	lastSaveVersion () const
	Returns the QGIS version which the project was last saved using.
QString	layerIsEmbedded (const QString &id) const
	Returns the source project file path if the layer with matching id is embedded from other project file.
template<typename T >
QVector< T >	layers () const
	Returns a list of registered map layers with a specified layer type.
QgsMapLayerStore *	layerStore ()
	Returns a pointer to the project's internal layer store.
const QgsMapLayerStore *	layerStore () const
	Returns a pointer to the project's internal layer store.
QgsLayerTreeRegistryBridge *	layerTreeRegistryBridge () const
	Returns pointer to the helper class that synchronizes map layer registry with layer tree.
QgsLayerTree *	layerTreeRoot () const
	Returns pointer to the root (invisible) node of the project's layer tree.
QgsLayoutManager *	layoutManager ()
	Returns the project's layout manager, which manages print layouts, atlases and reports within the project.
const QgsLayoutManager *	layoutManager () const
	Returns the project's layout manager, which manages print layouts, atlases and reports within the project.
bool	loadFunctionsFromProject (bool force=false)
	Loads python expression functions stored in the currrent project.
QgsAnnotationLayer *	mainAnnotationLayer ()
	Returns the main annotation layer associated with the project.
Q_INVOKABLE QgsMapLayer *	mapLayer (const QString &layerId) const
	Retrieve a pointer to a registered layer by layer ID.
template<class T >
T	mapLayer (const QString &layerId) const
	Retrieve a pointer to a registered layer by layerId converted to type T.
QMap< QString, QgsMapLayer * >	mapLayers (const bool validOnly=false) const
	Returns a map of all registered layers by layer ID.
Q_INVOKABLE QList< QgsMapLayer * >	mapLayersByName (const QString &layerName) const
	Retrieve a list of matching registered layers by layer name.
QList< QgsMapLayer * >	mapLayersByShortName (const QString &shortName) const
	Retrieves a list of matching registered layers by layer shortName.
template<typename T >
QVector< T >	mapLayersByShortName (const QString &shortName) const
	Retrieves a list of matching registered layers by layer shortName with a specified layer type, if layer's short name is empty a match with layer's name is attempted.
Q_DECL_DEPRECATED QVector< double >	mapScales () const
	Returns the list of custom project map scales.
QgsMapThemeCollection *	mapThemeCollection ()
	Returns pointer to the project's map theme collection.
const QgsProjectMetadata &	metadata () const
	Returns a reference to the project's metadata store.
Q_DECL_DEPRECATED QStringList	nonIdentifiableLayers () const
	Gets the list of layers which currently should not be taken into account on map identification.
QString	originalPath () const
	Returns the original path associated with the project.
QgsPathResolver	pathResolver () const
	Returns path resolver object with considering whether the project uses absolute or relative paths and using current project's path.
QString	presetHomePath () const
	Returns any manual project home path setting, or an empty string if not set.
QgsProjectStorage *	projectStorage () const
	Returns pointer to project storage implementation that handles read/write of the project file.
bool	read (const QString &filename, Qgis::ProjectReadFlags flags=Qgis::ProjectReadFlags())
	Reads given project file from the given file.
bool	read (Qgis::ProjectReadFlags flags=Qgis::ProjectReadFlags())
	Reads the project from its currently associated file (see fileName() ).
bool	readBoolEntry (const QString &scope, const QString &key, bool def=false, bool *ok=nullptr) const
	Reads a boolean from the specified scope and key.
double	readDoubleEntry (const QString &scope, const QString &key, double def=0, bool *ok=nullptr) const
	Reads a double from the specified scope and key.
QString	readEntry (const QString &scope, const QString &key, const QString &def=QString(), bool *ok=nullptr) const
	Reads a string from the specified scope and key.
bool	readLayer (const QDomNode &layerNode)
	Reads the layer described in the associated DOM node.
QStringList	readListEntry (const QString &scope, const QString &key, const QStringList &def=QStringList(), bool *ok=nullptr) const
	Reads a string list from the specified scope and key.
int	readNumEntry (const QString &scope, const QString &key, int def=0, bool *ok=nullptr) const
	Reads an integer from the specified scope and key.
QString	readPath (const QString &filename) const
	Transforms a filename read from the project file to an absolute path.
QgsRelationManager *	relationManager () const
void	reloadAllLayers ()
	Reload all registered layer's provider data caches, synchronising the layer with any changes in the datasource.
void	removeAllMapLayers ()
	Removes all registered layers.
bool	removeAttachedFile (const QString &path)
	Removes the attached file.
bool	removeEntry (const QString &scope, const QString &key)
	Remove the given key from the specified scope.
void	removeMapLayer (const QString &layerId)
	Remove a layer from the registry by layer ID.
void	removeMapLayer (QgsMapLayer *layer)
	Remove a layer from the registry.
void	removeMapLayers (const QList< QgsMapLayer * > &layers)
	Remove a set of layers from the registry.
void	removeMapLayers (const QStringList &layerIds)
	Remove a set of layers from the registry by layer ID.
Q_DECL_DEPRECATED QSet< QgsMapLayer * >	requiredLayers () const
	Returns a set of map layers that are required in the project and therefore they should not get removed from the project.
QString	resolveAttachmentIdentifier (const QString &identifier) const
	Resolves an attachment identifier to a attachment file path.
QString	saveUser () const
	Returns the user name that did the last save.
QString	saveUserFullName () const
	Returns the full user name that did the last save.
QColor	selectionColor () const
	Returns the color used to highlight selected features.
QgsSensorManager *	sensorManager ()
	Returns the project's sensor manager, which manages sensors within the project.
const QgsSensorManager *	sensorManager () const
	Returns the project's sensor manager, which manages sensors within the project.
void	setAreaUnits (Qgis::AreaUnit unit)
	Sets the default area measurement units for the project.
Q_DECL_DEPRECATED void	setAutoTransaction (bool autoTransaction)
	Transactional editing means that on supported datasources (postgres databases) the edit state of all tables that originate from the same database are synchronized and executed in a server side transaction.
void	setAvoidIntersectionsLayers (const QList< QgsVectorLayer * > &layers)
	Sets the list of layers with which intersections should be avoided.
void	setAvoidIntersectionsMode (const Qgis::AvoidIntersectionsMode mode)
	Sets the avoid intersections mode.
void	setBackgroundColor (const QColor &color)
	Sets the default background color used by default map canvases.
void	setBadLayerHandler (QgsProjectBadLayerHandler *handler)
	Change handler for missing layers.
void	setCrs (const QgsCoordinateReferenceSystem &crs, bool adjustEllipsoid=false)
	Sets the project's native coordinate reference system.
void	setCustomVariables (const QVariantMap &customVariables)
	A map of custom project variables.
void	setDistanceUnits (Qgis::DistanceUnit unit)
	Sets the default distance measurement units for the project.
void	setElevationShadingRenderer (const QgsElevationShadingRenderer &elevationShadingRenderer)
	Sets the elevation shading renderer used for global map shading.
void	setEllipsoid (const QString &ellipsoid)
	Sets the project's ellipsoid from a proj string representation, e.g., "WGS84".
Q_DECL_DEPRECATED void	setEvaluateDefaultValues (bool evaluateDefaultValues)
	Defines if default values should be evaluated on provider side when requested and not when committed.
void	setFileName (const QString &name)
	Sets the file name associated with the project.
void	setFilePathStorage (Qgis::FilePathType type)
	Sets the type of paths used when storing file paths in a QGS/QGZ project file.
void	setFlag (Qgis::ProjectFlag flag, bool enabled=true)
	Sets whether a project flag is enabled.
void	setFlags (Qgis::ProjectFlags flags)
	Sets the project's flags, which dictate the behavior of the project.
void	setLabelingEngineSettings (const QgsLabelingEngineSettings &settings)
	Sets project's global labeling engine settings.
Q_DECL_DEPRECATED void	setMapScales (const QVector< double > &scales)
	Sets the list of custom project map scales.
void	setMetadata (const QgsProjectMetadata &metadata)
	Sets the project's metadata store.
Q_DECL_DEPRECATED void	setNonIdentifiableLayers (const QList< QgsMapLayer * > &layers)
	Set a list of layers which should not be taken into account on map identification.
Q_DECL_DEPRECATED void	setNonIdentifiableLayers (const QStringList &layerIds)
	Set a list of layers which should not be taken into account on map identification.
void	setOriginalPath (const QString &path)
	Sets the original path associated with the project.
void	setProjectColors (const QgsNamedColorList &colors)
	Sets the colors for the project's color scheme (see QgsProjectColorScheme).
Q_DECL_DEPRECATED void	setRequiredLayers (const QSet< QgsMapLayer * > &layers)
	Configures a set of map layers that are required in the project and therefore they should not get removed from the project.
void	setSelectionColor (const QColor &color)
	Sets the color used to highlight selected features.
void	setTitle (const QString &title)
	Sets the project's title.
void	setTopologicalEditing (bool enabled)
	Convenience function to set topological editing.
bool	setTransactionMode (Qgis::TransactionMode transactionMode)
	Set transaction mode.
void	setTransformContext (const QgsCoordinateTransformContext &context)
	Sets the project's coordinate transform context, which stores various information regarding which datum transforms should be used when transforming points from a source to destination coordinate reference system.
Q_DECL_DEPRECATED void	setTrustLayerMetadata (bool trust)
	Sets the trust option allowing to indicate if the extent has to be read from the XML document when data source has no metadata or if the data provider has to determine it.
Q_DECL_DEPRECATED void	setUseProjectScales (bool enabled)
	Sets whether project mapScales() are enabled.
bool	setVerticalCrs (const QgsCoordinateReferenceSystem &crs, QString *errorMessage=nullptr)
	Sets the project's vertical coordinate reference system.
QgsSnappingConfig	snappingConfig () const
	The snapping configuration for this project.
QgsProjectStyleSettings *	styleSettings ()
	Returns the project's style settings, which contains settings and properties relating to how a QgsProject should handle styling.
const QgsProjectStyleSettings *	styleSettings () const
	Returns the project's style settings, which contains settings and properties relating to how a QgsProject should handle styling.
QStringList	subkeyList (const QString &scope, const QString &key) const
	Returns a list of child keys which contain other keys that exist within the the specified scope and key.
QgsMapLayer *	takeMapLayer (QgsMapLayer *layer)
	Takes a layer from the registry.
QgsProjectTimeSettings *	timeSettings ()
	Returns the project's time settings, which contains the project's temporal range and other time based settings.
const QgsProjectTimeSettings *	timeSettings () const
	Returns the project's time settings, which contains the project's temporal range and other time based settings.
QString	title () const
	Returns the project's title.
bool	topologicalEditing () const
	Convenience function to query topological editing status.
QgsTransactionGroup *	transactionGroup (const QString &providerKey, const QString &connString)
	Returns the matching transaction group from a provider key and connection string.
QMap< QPair< QString, QString >, QgsTransactionGroup * >	transactionGroups ()
	Map of transaction groups.
Qgis::TransactionMode	transactionMode () const
	Returns the transaction mode.
QgsCoordinateTransformContext	transformContext () const
	Returns a copy of the project's coordinate transform context, which stores various information regarding which datum transforms should be used when transforming points from a source to destination coordinate reference system.
QString	translate (const QString &context, const QString &sourceText, const char *disambiguation=nullptr, int n=-1) const override
	Translates a string using the Qt QTranslator mechanism.
Q_DECL_DEPRECATED bool	trustLayerMetadata () const
	Returns true if the trust option is activated, false otherwise.
Q_DECL_DEPRECATED bool	useProjectScales () const
	Returns true if project mapScales() are enabled.
int	validCount () const
	Returns the number of registered valid layers.
QgsCoordinateReferenceSystem	verticalCrs () const
	Returns the project's vertical coordinate reference system.
QgsProjectViewSettings *	viewSettings ()
	Returns the project's view settings, which contains settings and properties relating to how a QgsProject should be viewed and behave inside a map canvas (e.g.
const QgsProjectViewSettings *	viewSettings () const
	Returns the project's view settings, which contains settings and properties relating to how a QgsProject should be viewed and behave inside a map canvas (e.g.
QgsMapViewsManager *	viewsManager ()
	Returns the project's views manager, which manages map views (including 3d maps) in the project.
const QgsMapViewsManager *	viewsManager () const
	Returns the project's views manager, which manages map views (including 3d maps) in the project.
bool	write ()
	Writes the project to its current associated file (see fileName() ).
bool	write (const QString &filename)
	Writes the project to a file.
bool	writeEntry (const QString &scope, const QString &key, bool value)
	Write a boolean value to the project file.
bool	writeEntry (const QString &scope, const QString &key, const QString &value)
	Write a string value to the project file.
bool	writeEntry (const QString &scope, const QString &key, const QStringList &value)
	Write a string list value to the project file.
bool	writeEntry (const QString &scope, const QString &key, double value)
	Write a double value to the project file.
bool	writeEntry (const QString &scope, const QString &key, int value)
	Write an integer value to the project file.
QString	writePath (const QString &filename) const
	Prepare a filename to save it to the project file.
Public Member Functions inherited from QgsExpressionContextGenerator
virtual	~QgsExpressionContextGenerator ()=default
Public Member Functions inherited from QgsExpressionContextScopeGenerator
virtual	~QgsExpressionContextScopeGenerator ()=default
Public Member Functions inherited from QgsProjectTranslator
virtual	~QgsProjectTranslator ()=default

Static Public Member Functions
static QgsProject *	instance ()
	Returns the QgsProject singleton instance.
static void	setInstance (QgsProject *project)
	Set the current project singleton instance to project.

Properties
Qgis::AreaUnit	areaUnits
QList< QgsVectorLayer * >	avoidIntersectionsLayers
Qgis::AvoidIntersectionsMode	avoidIntersectionsMode
QColor	backgroundColor
QgsCoordinateReferenceSystem	crs
QgsProjectDisplaySettings *	displaySettings
Qgis::DistanceUnit	distanceUnits
QString	ellipsoid
QString	fileName
QString	homePath
QgsMapThemeCollection *	mapThemeCollection
QgsProjectMetadata	metadata
QStringList	nonIdentifiableLayers
QgsRelationManager *	relationManager
QColor	selectionColor
QgsSnappingConfig	snappingConfig
bool	topologicalEditing
Qgis::TransactionMode	transactionMode
QgsCoordinateTransformContext	transformContext

Friends
class	QgsApplication
class	QgsProjectDirtyBlocker
class	QgsProviderRegistry
class	QgsServer
class	TestQgsProject

Detailed Description

Encapsulates a QGIS project, including sets of map layers and their styles, layouts, annotations, canvases, etc.

QgsProject is available both as a singleton (QgsProject.instance()) and for use as standalone objects. The QGIS project singleton always gives access to the canonical project reference open within the main QGIS application.

Note

QgsProject has two general kinds of state to make persistent. (I.e., to read and write.) First, QGIS proprietary information. Second plugin information.

Definition at line 106 of file qgsproject.h.

Member Enumeration Documentation

DataDefinedServerProperty

enum class QgsProject::DataDefinedServerProperty : int

strong

Data defined properties.

Overrides of user defined server parameters are stored in a property collection and they can be retrieved using the indexes specified in this enum.

Since

QGIS 3.14

Enumerator
NoProperty	No property.
AllProperties	All properties for item.
WMSOnlineResource	Alias.

Definition at line 141 of file qgsproject.h.

Constructor & Destructor Documentation

QgsProject()

QgsProject::QgsProject ( QObject *  parent = nullptr, Qgis::ProjectCapabilities  capabilities = Qgis::ProjectCapability::ProjectStyles  )

explicit

Create a new QgsProject.

Most of the time you want to use QgsProject.instance() instead as many components of QGIS work with the singleton.

Since QGIS 3.26.1 the capabilities argument specifies optional capabilities which can be selectively enabled for the project. These affect the QgsProject object for its entire lifetime.

Definition at line 371 of file qgsproject.cpp.

~QgsProject()

QgsProject::~QgsProject ( )

override

Definition at line 461 of file qgsproject.cpp.

Member Function Documentation

aboutToBeCleared

void QgsProject::aboutToBeCleared ( )

signal

Emitted when the project is about to be cleared.

See also

clear()

Since

QGIS 3.34

absoluteFilePath()

QString QgsProject::absoluteFilePath

(

)

const

Returns full absolute path to the project file if the project is stored in a file system - derived from fileName().

Returns empty string when the project is stored in a project storage (there is no concept of paths for custom project storages).

Since

QGIS 3.2

Definition at line 884 of file qgsproject.cpp.

absolutePath()

QString QgsProject::absolutePath

(

)

const

Returns full absolute path to the project folder if the project is stored in a file system - derived from fileName().

Returns empty string when the project is stored in a project storage (there is no concept of paths for custom project storages).

Since

QGIS 3.2

Definition at line 871 of file qgsproject.cpp.

accept()

bool QgsProject::accept

(

QgsStyleEntityVisitorInterface *

visitor

)

const

Accepts the specified style entity visitor, causing it to visit all style entities associated with the project.

Returns true if the visitor should continue visiting other objects, or false if visiting should be canceled.

Since

QGIS 3.10

Definition at line 5236 of file qgsproject.cpp.

addMapLayer()

QgsMapLayer * QgsProject::addMapLayer	(	QgsMapLayer *	mapLayer,
		bool	addToLegend = true,
		bool	takeOwnership = true
	)

Add a layer to the map of loaded layers.

The layersAdded() and layerWasAdded() signals will always be emitted. The legendLayersAdded() signal is emitted only if addToLegend is true. If you are adding multiple layers at once, you should use addMapLayers() instead.

Parameters

mapLayer	A layer to add to the registry
addToLegend	If true (by default), the layer will be added to the legend and to the main canvas. If you have a private layer you can set this parameter to false to hide it.
takeOwnership	Ownership will be transferred to the layer registry. If you specify false here you have take care of deleting the layer yourself. Not available in Python.

Returns

nullptr if unable to add layer, otherwise pointer to newly added layer

See also

addMapLayers

Note

As a side-effect QgsProject is made dirty.

Use addMapLayers if adding more than one layer at a time

takeOwnership is not available in the Python bindings - the registry will always take ownership

See also

addMapLayers()

Definition at line 4772 of file qgsproject.cpp.

addMapLayers()

QList< QgsMapLayer * > QgsProject::addMapLayers	(	const QList< QgsMapLayer * > &	mapLayers,
		bool	addToLegend = true,
		bool	takeOwnership = true
	)

Add a list of layers to the map of loaded layers.

The layersAdded() and layerWasAdded() signals will always be emitted. The legendLayersAdded() signal is emitted only if addToLegend is true.

Parameters

mapLayers	A list of layer which should be added to the registry
addToLegend	If true (by default), the layers will be added to the legend and to the main canvas. If you have a private layer you can set this parameter to false to hide it.
takeOwnership	Ownership will be transferred to the layer registry. If you specify false here you have take care of deleting the layers yourself. Not available in Python.

Returns

a list of the map layers that were added successfully. If a layer or already exists in the registry, it will not be part of the returned QList.

Note

As a side-effect QgsProject is made dirty.

takeOwnership is not available in the Python bindings - the registry will always take ownership

See also

addMapLayer()

Definition at line 4730 of file qgsproject.cpp.

annotationManager() [1/2]

QgsAnnotationManager * QgsProject::annotationManager

(

)

Returns pointer to the project's annotation manager.

Definition at line 4395 of file qgsproject.cpp.

annotationManager() [2/2]

const QgsAnnotationManager * QgsProject::annotationManager

(

)

const

Returns a const pointer to the project's annotation manager.

Definition at line 4402 of file qgsproject.cpp.

areaUnits()

Qgis::AreaUnit QgsProject::areaUnits ( ) const

inline

Convenience function to query default area measurement units for project.

See also

distanceUnits()

Definition at line 783 of file qgsproject.h.

areaUnitsChanged

void QgsProject::areaUnitsChanged ( )

signal

Emitted when the default area units changes.

See also

setAreaUnits()

Since

QGIS 3.28

attachedFiles()

QStringList QgsProject::attachedFiles

(

)

const

Returns a map of all attached files with identifier and real paths.

See also

createAttachedFile()

Since

QGIS 3.22

Definition at line 5019 of file qgsproject.cpp.

attachmentIdentifier()

QString QgsProject::attachmentIdentifier

(

const QString &

attachedFile

)

const

Returns an identifier for an attachment file path An attachment identifier is a string which does not depend on the project archive storage location.

Parameters

attachedFile

An attachment file path

Returns

An identifier for the attached file

Since

QGIS 3.22

Definition at line 5044 of file qgsproject.cpp.

autoTransaction()

bool QgsProject::autoTransaction

(

)

const

Transactional editing means that on supported datasources (postgres databases) the edit state of all tables that originate from the same database are synchronized and executed in a server side transaction.

Deprecated:

QGIS 3.26. Use transactionMode instead.

Definition at line 4464 of file qgsproject.cpp.

auxiliaryStorage() [1/2]

QgsAuxiliaryStorage * QgsProject::auxiliaryStorage

(

)

Returns the current auxiliary storage.

Definition at line 5000 of file qgsproject.cpp.

auxiliaryStorage() [2/2]

const QgsAuxiliaryStorage * QgsProject::auxiliaryStorage

(

)

const

Returns the current const auxiliary storage.

Definition at line 4993 of file qgsproject.cpp.

avoidIntersectionsLayers()

QList< QgsVectorLayer * > QgsProject::avoidIntersectionsLayers

(

)

const

A list of layers with which intersections should be avoided.

Definition at line 2806 of file qgsproject.cpp.

avoidIntersectionsLayersChanged

void QgsProject::avoidIntersectionsLayersChanged ( )

signal

Emitted whenever avoidIntersectionsLayers has changed.

avoidIntersectionsMode()

Qgis::AvoidIntersectionsMode QgsProject::avoidIntersectionsMode ( ) const

inline

Returns the current avoid intersections mode.

Since

QGIS 3.14

Definition at line 1133 of file qgsproject.h.

avoidIntersectionsModeChanged

void QgsProject::avoidIntersectionsModeChanged ( )

signal

Emitted whenever the avoid intersections mode has changed.

Since

QGIS 3.14

backgroundColor()

QColor QgsProject::backgroundColor

(

)

const

Returns the default background color used by default map canvases.

See also

setBackgroundColor()

Since

QGIS 3.10

Definition at line 5152 of file qgsproject.cpp.

backgroundColorChanged

void QgsProject::backgroundColorChanged ( )

signal

Emitted whenever the project's canvas background color has been changed.

See also

setBackgroundColor()

Since

QGIS 3.10

baseName()

QString QgsProject::baseName

(

)

const

Returns the base name of the project file without the path and without extension - derived from fileName().

Since

QGIS 3.2

Definition at line 898 of file qgsproject.cpp.

bookmarkManager() [1/2]

QgsBookmarkManager * QgsProject::bookmarkManager

(

)

Returns the project's bookmark manager, which manages bookmarks within the project.

Since

QGIS 3.10

Definition at line 4275 of file qgsproject.cpp.

bookmarkManager() [2/2]

const QgsBookmarkManager * QgsProject::bookmarkManager

(

)

const

Returns the project's bookmark manager, which manages bookmarks within the project.

Note

not available in Python bindings

Since

QGIS 3.10

Definition at line 4268 of file qgsproject.cpp.

capabilities()

Qgis::ProjectCapabilities QgsProject::capabilities ( ) const

inline

Returns the project's capabilities, which dictate optional functionality which can be selectively enabled for a QgsProject object.

Since

QGIS 3.26.1

Definition at line 198 of file qgsproject.h.

cleanFunctionsFromProject()

void QgsProject::cleanFunctionsFromProject

(

)

Unloads python expression functions stored in the current project and reloads local functions from the user profile.

Note

not available in Python bindings

Since

QGIS 3.40

Definition at line 5322 of file qgsproject.cpp.

clear()

void QgsProject::clear

(

)

Clears the project, removing all settings and resetting it back to an empty, default state.

See also

cleared()

Definition at line 1164 of file qgsproject.cpp.

cleared

void QgsProject::cleared ( )

signal

Emitted when the project is cleared (and additionally when an open project is cleared just before a new project is read).

See also

clear()

Since

QGIS 3.2

commitChanges

bool QgsProject::commitChanges ( QStringList &  commitErrors, bool  stopEditing = true, QgsVectorLayer *  vectorLayer = nullptr  )

slot

Attempts to commit to the underlying data provider any buffered changes made since the last to call to startEditing().

Returns the result of the attempt. If a commit fails (i.e. false is returned), the in-memory changes are left untouched and are not discarded. This allows editing to continue if the commit failed on e.g. a disallowed value in a Postgres database - the user can re-edit and try again.

The commits occur in distinct stages, (add attributes, add features, change attribute values, change geometries, delete features, delete attributes) so if a stage fails, it can be difficult to roll back cleanly. Therefore any error message returned by commitErrors also includes which stage failed so that the user has some chance of repairing the damage cleanly.

Parameters

commitErrors	will be set to a list of descriptive errors if the commit fails.
stopEditing	if set to false, the layer will stay in editing mode. Otherwise the layer editing mode will be disabled if the commit is successful.
vectorLayer	for which the changes will be committed. For buffered transactions this parameter is not mandatory, as the changes from all layers will be committed.

Returns

true if the commit was successful.

See also

startEditing()

rollBack()

Since

QGIS 3.26

Definition at line 744 of file qgsproject.cpp.

count()

int QgsProject::count

(

)

const

Returns the number of registered layers.

Definition at line 4535 of file qgsproject.cpp.

createAttachedFile()

QString QgsProject::createAttachedFile

(

const QString &

nameTemplate

)

Attaches a file to the project.

Parameters

nameTemplate

Any filename template, used as a basename for attachment file, i.e. "myfile.ext"

Returns

The path to the file where the contents can be written to.

Note

If the attachment file is used as a source for a project layer, the attachment will be removed automatically when the layer is deleted.

Since

QGIS 3.22

Definition at line 5007 of file qgsproject.cpp.

createEmbeddedGroup()

QgsLayerTreeGroup * QgsProject::createEmbeddedGroup	(	const QString &	groupName,
		const QString &	projectFilePath,
		const QStringList &	invisibleLayers,
		Qgis::ProjectReadFlags	flags = Qgis::ProjectReadFlags()
	)

Create layer group instance defined in an arbitrary project file.

The optional flags argument can be used to control layer reading behavior.

Definition at line 4016 of file qgsproject.cpp.

createEmbeddedLayer()

bool QgsProject::createEmbeddedLayer	(	const QString &	layerId,
		const QString &	projectFilePath,
		QList< QDomNode > &	brokenNodes,
		bool	saveFlag = true,
		Qgis::ProjectReadFlags	flags = Qgis::ProjectReadFlags()
	)

Creates a maplayer instance defined in an arbitrary project file.

Caller takes ownership.

The optional flags argument can be used to specify flags which control layer reading.

Returns

the layer or 0 in case of error

Note

not available in Python bindings

Definition at line 3920 of file qgsproject.cpp.

createExpressionContext()

QgsExpressionContext QgsProject::createExpressionContext ( ) const

overridevirtual

This method needs to be reimplemented in all classes which implement this interface and return an expression context.

Implements QgsExpressionContextGenerator.

Definition at line 2838 of file qgsproject.cpp.

createExpressionContextScope()

QgsExpressionContextScope * QgsProject::createExpressionContextScope ( ) const

overridevirtual

This method needs to be reimplemented in all classes which implement this interface and return an expression context scope.

Implements QgsExpressionContextScopeGenerator.

Definition at line 2850 of file qgsproject.cpp.

crs()

QgsCoordinateReferenceSystem QgsProject::crs

(

)

const

Returns the project's native coordinate reference system.

Warning

Since QGIS 3.38, consider using crs3D() whenever transforming 3D data or whenever z/elevation value handling is important.

See also

setCrs()

crs3D()

verticalCrs()

ellipsoid()

crsChanged()

Definition at line 938 of file qgsproject.cpp.

crs3D()

QgsCoordinateReferenceSystem QgsProject::crs3D

(

)

const

Returns the CRS to use for the project when transforming 3D data, or when z/elevation value handling is important.

The returned CRS will take into account verticalCrs() when appropriate, e.g. it may return a compound CRS consisting of crs() + verticalCrs(). This method may still return a 2D CRS, e.g in the case that crs() is a 2D CRS and no verticalCrs() has been set for the project. Check QgsCoordinateReferenceSystem::type() on the returned value to determine the type of CRS returned by this method.

Warning

It is NOT guaranteed that the returned CRS will actually be a 3D CRS, but rather it is guaranteed that the returned CRS is ALWAYS the most appropriate CRS to use when handling 3D data.

See also

crs()

verticalCrs()

crs3DChanged()

Since

QGIS 3.38

Definition at line 946 of file qgsproject.cpp.

crs3DChanged

void QgsProject::crs3DChanged ( )

signal

Emitted when the crs3D() of the project has changed.

See also

crs3D()

crsChanged()

verticalCrsChanged()

ellipsoidChanged()

Since

QGIS 3.38

crsChanged

void QgsProject::crsChanged ( )

signal

Emitted when the crs() of the project has changed.

See also

crs()

setCrs()

verticalCrsChanged()

ellipsoidChanged()

customVariables()

QVariantMap QgsProject::customVariables

(

)

const

A map of custom project variables.

To get all available variables including generated ones use QgsExpressionContextUtils::projectScope() instead.

Definition at line 2741 of file qgsproject.cpp.

customVariablesChanged

void QgsProject::customVariablesChanged ( )

signal

Emitted whenever the expression variables stored in the project have been changed.

dataDefinedServerProperties

QgsPropertyCollection QgsProject::dataDefinedServerProperties ( ) const

slot

Returns the data defined properties used for overrides in user defined server parameters.

Since

QGIS 3.14

Definition at line 716 of file qgsproject.cpp.

defaultCrsForNewLayers()

QgsCoordinateReferenceSystem QgsProject::defaultCrsForNewLayers

(

)

const

Returns the default CRS for new layers based on the settings and the current project CRS.

Definition at line 4904 of file qgsproject.cpp.

dirtySet

void QgsProject::dirtySet ( )

signal

Emitted when setDirty(true) is called.

Note

As opposed to isDirtyChanged(), this signal is invoked every time setDirty(true) is called, regardless of whether the project was already dirty.

Since

QGIS 3.20

displaySettings() [1/2]

QgsProjectDisplaySettings * QgsProject::displaySettings

(

)

Returns the project's display settings, which contains settings and properties relating to how a QgsProject should display values such as map coordinates and bearings.

Since

QGIS 3.12

displaySettings() [2/2]

const QgsProjectDisplaySettings * QgsProject::displaySettings

(

)

const

Returns the project's display settings, which contains settings and properties relating to how a QgsProject should display values such as map coordinates and bearings.

Note

not available in Python bindings

Since

QGIS 3.12

Definition at line 4353 of file qgsproject.cpp.

distanceUnits()

Qgis::DistanceUnit QgsProject::distanceUnits ( ) const

inline

Convenience function to query default distance measurement units for project.

See also

setDistanceUnits()

areaUnits()

Definition at line 770 of file qgsproject.h.

distanceUnitsChanged

void QgsProject::distanceUnitsChanged ( )

signal

Emitted when the default distance units changes.

See also

setDistanceUnits()

Since

QGIS 3.28

dumpProperties()

void QgsProject::dumpProperties

(

)

const

Dump out current project properties to stderr.

Definition at line 3828 of file qgsproject.cpp.

editBufferGroup()

QgsVectorLayerEditBufferGroup * QgsProject::editBufferGroup

(

)

Returns the edit buffer group.

Since

QGIS 3.26

Definition at line 4897 of file qgsproject.cpp.

elevationProperties() [1/2]

QgsProjectElevationProperties * QgsProject::elevationProperties

(

)

Returns the project's elevation properties, which contains the project's elevation related settings.

Since

QGIS 3.26

Definition at line 4346 of file qgsproject.cpp.

elevationProperties() [2/2]

const QgsProjectElevationProperties * QgsProject::elevationProperties

(

)

const

Returns the project's elevation properties, which contains the project's elevation related settings.

Note

not available in Python bindings

Since

QGIS 3.26

Definition at line 4339 of file qgsproject.cpp.

elevationShadingRenderer()

QgsElevationShadingRenderer QgsProject::elevationShadingRenderer

(

)

const

Returns the elevation shading renderer used for map shading.

Since

QGIS 3.30

Definition at line 5266 of file qgsproject.cpp.

elevationShadingRendererChanged

void QgsProject::elevationShadingRendererChanged ( )

signal

Emitted when the map shading renderer changes.

Since

QGIS 3.30

ellipsoid()

QString QgsProject::ellipsoid

(

)

const

Returns a proj string representing the project's ellipsoid setting, e.g., "WGS84".

See also

setEllipsoid()

crs()

verticalCrs()

Definition at line 985 of file qgsproject.cpp.

ellipsoidChanged

void QgsProject::ellipsoidChanged ( const QString &  ellipsoid )

signal

Emitted when the project ellipsoid is changed.

See also

setEllipsoid()

ellipsoid()

entryList()

QStringList QgsProject::entryList	(	const QString &	scope,
		const QString &	key
	)		const

Returns a list of child keys with values which exist within the the specified scope and key.

This method does not return keys that contain other keys. See subkeyList() to retrieve keys which contain other keys.

Note

equivalent to QgsSettings entryList()

Definition at line 3790 of file qgsproject.cpp.

error()

QString QgsProject::error

(

)

const

Returns error message from previous read/write.

Definition at line 3886 of file qgsproject.cpp.

evaluateDefaultValues()

bool QgsProject::evaluateDefaultValues

(

)

const

Should default values be evaluated on provider side when requested and not when committed.

Deprecated:

QGIS 3.40. Test whether the flags() method returns the Qgis::ProjectFlag::EvaluateDefaultValuesOnProviderSide flag instead.

Definition at line 4117 of file qgsproject.cpp.

fileInfo()

QFileInfo QgsProject::fileInfo

(

)

const

Returns QFileInfo object for the project's associated file.

Note

The use of this method is discouraged since QGIS 3.2 as it only works with project files stored in the file system. It is recommended to use absoluteFilePath(), baseName(), lastModifiedTime() as replacements that are aware of the fact that projects may be saved in other project storages.

See also

fileName()

Deprecated:

QGIS 3.2. Use absoluteFilePath(), baseName() or lastModifiedTime() instead.

Definition at line 840 of file qgsproject.cpp.

fileName()

QString QgsProject::fileName

(

)

const

Returns the project's file name.

This is the file or the storage URI which contains the project's XML representation.

See also

setFileName()

fileInfo()

Definition at line 818 of file qgsproject.cpp.

fileNameChanged

void QgsProject::fileNameChanged ( )

signal

Emitted when the file name of the project changes.

filePathStorage()

Qgis::FilePathType QgsProject::filePathStorage

(

)

const

Returns the type of paths used when storing file paths in a QGS/QGZ project file.

See also

setFilePathStorage()

Since

QGIS 3.22

Definition at line 915 of file qgsproject.cpp.

flags()

Qgis::ProjectFlags QgsProject::flags ( ) const

inline

Returns the project's flags, which dictate the behavior of the project.

See also

setFlags()

setFlag()

Since

QGIS 3.26

Definition at line 208 of file qgsproject.h.

generateTsFile()

void QgsProject::generateTsFile

(

const QString &

locale

)

Triggers the collection strings of .qgs to be included in ts file and calls writeTsFile()

Since

QGIS 3.4

Definition at line 5205 of file qgsproject.cpp.

gpsSettings() [1/2]

QgsProjectGpsSettings * QgsProject::gpsSettings

(

)

Returns the project's GPS settings, which contains settings and properties relating to how a QgsProject should interact with a GPS device.

Since

QGIS 3.30

Definition at line 4374 of file qgsproject.cpp.

gpsSettings() [2/2]

const QgsProjectGpsSettings * QgsProject::gpsSettings

(

)

const

Returns the project's GPS settings, which contains settings and properties relating to how a QgsProject should interact with a GPS device.

Note

not available in Python bindings

Since

QGIS 3.30

Definition at line 4367 of file qgsproject.cpp.

homePath()

QString QgsProject::homePath

(

)

const

Returns the project's home path.

This will either be a manually set home path (see presetHomePath()) or the path containing the project file itself.

This method always returns the absolute path to the project's home. See presetHomePath() to retrieve any manual project home path override (e.g. relative home paths).

See also

setPresetHomePath()

presetHomePath()

homePathChanged()

Definition at line 4170 of file qgsproject.cpp.

homePathChanged

void QgsProject::homePathChanged ( )

signal

Emitted when the home path of the project changes.

See also

setPresetHomePath()

homePath()

presetHomePath()

instance()

QgsProject * QgsProject::instance ( )

static

Returns the QgsProject singleton instance.

Definition at line 483 of file qgsproject.cpp.

isDirty()

bool QgsProject::isDirty

(

)

const

Returns true if the project has been modified since the last write()

Definition at line 594 of file qgsproject.cpp.

isDirtyChanged

void QgsProject::isDirtyChanged ( bool  dirty )

signal

Emitted when the project dirty status changes.

Parameters

dirty

true if the project is in a dirty state and has pending unsaved changes.

Since

QGIS 3.2

isZipped()

bool QgsProject::isZipped

(

)

const

Returns true if the project comes from a zip archive, false otherwise.

Definition at line 4723 of file qgsproject.cpp.

labelingEngineSettings()

const QgsLabelingEngineSettings & QgsProject::labelingEngineSettings

(

)

const

Returns project's global labeling engine settings.

Definition at line 2784 of file qgsproject.cpp.

labelingEngineSettingsChanged

void QgsProject::labelingEngineSettingsChanged ( )

signal

Emitted when global configuration of the labeling engine changes.

lastModified()

QDateTime QgsProject::lastModified

(

)

const

Returns last modified time of the project file as returned by the file system (or other project storage).

Since

QGIS 3.2

Definition at line 855 of file qgsproject.cpp.

lastSaveDateTime()

QDateTime QgsProject::lastSaveDateTime

(

)

const

Returns the date and time when the project was last saved.

Since

QGIS 3.14

Definition at line 580 of file qgsproject.cpp.

lastSaveVersion()

QgsProjectVersion QgsProject::lastSaveVersion

(

)

const

Returns the QGIS version which the project was last saved using.

Since

QGIS 3.14

Definition at line 587 of file qgsproject.cpp.

layerIsEmbedded()

QString QgsProject::layerIsEmbedded

(

const QString &

id

)

const

Returns the source project file path if the layer with matching id is embedded from other project file.

Returns an empty string if the matching layer is not embedded.

Definition at line 3908 of file qgsproject.cpp.

layerLoaded

void QgsProject::layerLoaded ( int  i, int  n  )

signal

Emitted when a layer from a projects was read.

Parameters

i	current layer
n	number of layers

layerRemoved

void QgsProject::layerRemoved ( const QString &  layerId )

signal

Emitted after a layer was removed from the registry.

Parameters

layerId

The ID of the layer removed.

Note

Consider using layersRemoved() instead

See also

layerWillBeRemoved()

layers()

template<typename T >

QVector< T > QgsProject::layers ( ) const

inline

Returns a list of registered map layers with a specified layer type.

Example

QVector<QgsVectorLayer*> vectorLayers = QgsProject.instance()->layers<QgsVectorLayer*>();

Note

not available in Python bindings

See also

mapLayers()

Definition at line 1260 of file qgsproject.h.

layersAdded

void QgsProject::layersAdded ( const QList< QgsMapLayer * > &  layers )

signal

Emitted when one or more layers were added to the registry.

This signal is also emitted for layers added to the registry, but not to the legend.

Parameters

layers

List of layers which have been added.

See also

legendLayersAdded()

layerWasAdded()

layersRemoved

void QgsProject::layersRemoved ( const QStringList &  layerIds )

signal

Emitted after one or more layers were removed from the registry.

Parameters

layerIds

A list of IDs of the layers which were removed.

See also

layersWillBeRemoved()

layerStore() [1/2]

QgsMapLayerStore * QgsProject::layerStore

(

)

Returns a pointer to the project's internal layer store.

Definition at line 2791 of file qgsproject.cpp.

layerStore() [2/2]

const QgsMapLayerStore * QgsProject::layerStore

(

)

const

Returns a pointer to the project's internal layer store.

Definition at line 2799 of file qgsproject.cpp.

layersWillBeRemoved [1/2]

void QgsProject::layersWillBeRemoved ( const QList< QgsMapLayer * > &  layers )

signal

Emitted when one or more layers are about to be removed from the registry.

Parameters

layers

A list of layers which are to be removed.

See also

layerWillBeRemoved()

layersRemoved()

layersWillBeRemoved [2/2]

void QgsProject::layersWillBeRemoved ( const QStringList &  layerIds )

signal

Emitted when one or more layers are about to be removed from the registry.

Parameters

layerIds

A list of IDs for the layers which are to be removed.

See also

layerWillBeRemoved()

layersRemoved()

layerTreeRegistryBridge()

QgsLayerTreeRegistryBridge * QgsProject::layerTreeRegistryBridge ( ) const

inline

Returns pointer to the helper class that synchronizes map layer registry with layer tree.

Definition at line 984 of file qgsproject.h.

layerTreeRoot()

QgsLayerTree * QgsProject::layerTreeRoot

(

)

const

Returns pointer to the root (invisible) node of the project's layer tree.

Definition at line 4381 of file qgsproject.cpp.

layerWasAdded

void QgsProject::layerWasAdded ( QgsMapLayer *  layer )

signal

Emitted when a layer was added to the registry.

Note

Consider using layersAdded() instead

See also

layersAdded()

layerWillBeRemoved [1/2]

void QgsProject::layerWillBeRemoved ( const QString &  layerId )

signal

Emitted when a layer is about to be removed from the registry.

Parameters

layerId

The ID of the layer to be removed.

Note

Consider using layersWillBeRemoved() instead

See also

layersWillBeRemoved()

layerRemoved()

layerWillBeRemoved [2/2]

void QgsProject::layerWillBeRemoved ( QgsMapLayer *  layer )

signal

Emitted when a layer is about to be removed from the registry.

Parameters

layer

The layer to be removed.

Note

Consider using layersWillBeRemoved() instead

See also

layersWillBeRemoved()

layerRemoved()

layoutManager() [1/2]

QgsLayoutManager * QgsProject::layoutManager

(

)

Returns the project's layout manager, which manages print layouts, atlases and reports within the project.

Definition at line 4247 of file qgsproject.cpp.

layoutManager() [2/2]

const QgsLayoutManager * QgsProject::layoutManager

(

)

const

Returns the project's layout manager, which manages print layouts, atlases and reports within the project.

Note

not available in Python bindings

Definition at line 4240 of file qgsproject.cpp.

legendLayersAdded

void QgsProject::legendLayersAdded ( const QList< QgsMapLayer * > &  layers )

signal

Emitted, when a layer was added to the registry and the legend.

Layers can also be private layers, which are signalled by layersAdded() and layerWasAdded() but will not be advertised by this signal.

Parameters

layers

List of QgsMapLayer which were added to the legend.

loadFunctionsFromProject()

bool QgsProject::loadFunctionsFromProject

(

bool

force = false

)

Loads python expression functions stored in the currrent project.

Parameters

force

Whether to check enablePythonEmbedded setting (default) or not.

Returns

Whether the project functions were loaded or not.

Note

not available in Python bindings

Since

QGIS 3.40

Definition at line 5303 of file qgsproject.cpp.

loadingLayer

void QgsProject::loadingLayer ( const QString &  layerName )

signal

Emitted when a layer is loaded.

loadingLayerMessageReceived

void QgsProject::loadingLayerMessageReceived ( const QString &  layerName, const QList< QgsReadWriteContext::ReadWriteMessage > &  messages  )

signal

Emitted when loading layers has produced some messages.

Parameters

layerName	the layer name
messages	a list of pairs of Qgis::MessageLevel and messages

Since

QGIS 3.2

mainAnnotationLayer()

QgsAnnotationLayer * QgsProject::mainAnnotationLayer

(

)

Returns the main annotation layer associated with the project.

This layer is always present in projects, and will always be rendered above any other map layers during map render jobs.

It forms the default location to place new annotation items which should appear above all map layers.

Since

QGIS 3.16

Definition at line 4846 of file qgsproject.cpp.

mapLayer() [1/2]

QgsMapLayer * QgsProject::mapLayer

(

const QString &

layerId

)

const

Retrieve a pointer to a registered layer by layer ID.

Parameters

layerId

ID of layer to retrieve

Returns

matching layer, or nullptr if no matching layer found

See also

mapLayersByName()

mapLayers()

Definition at line 4549 of file qgsproject.cpp.

mapLayer() [2/2]

template<class T >

T QgsProject::mapLayer ( const QString &  layerId ) const

inline

Retrieve a pointer to a registered layer by layerId converted to type T.

This is a convenience template. A nullptr will be returned if the layer is not found or if it cannot be cast to type T.

QgsVectorLayer *layer = project->mapLayer<QgsVectorLayer*>( layerId );

See also

mapLayer()

mapLayers()

Since

QGIS 3.6

Definition at line 1205 of file qgsproject.h.

mapLayers()

QMap< QString, QgsMapLayer * > QgsProject::mapLayers

(

const bool

validOnly = false

)

const

Returns a map of all registered layers by layer ID.

Parameters

validOnly

if set only valid layers will be returned

See also

mapLayer()

mapLayersByName()

layers()

Definition at line 4882 of file qgsproject.cpp.

mapLayersByName()

QList< QgsMapLayer * > QgsProject::mapLayersByName

(

const QString &

layerName

)

const

Retrieve a list of matching registered layers by layer name.

Parameters

layerName

name of layers to match

Returns

list of matching layers

See also

mapLayer()

mapLayers()

Definition at line 4557 of file qgsproject.cpp.

mapLayersByShortName() [1/2]

QList< QgsMapLayer * > QgsProject::mapLayersByShortName

(

const QString &

shortName

)

const

Retrieves a list of matching registered layers by layer shortName.

If layer's short name is empty a match with layer's name is attempted.

Returns

list of matching layers

See also

mapLayer()

mapLayers()

Since

QGIS 3.10

Definition at line 4564 of file qgsproject.cpp.

mapLayersByShortName() [2/2]

template<typename T >

QVector< T > QgsProject::mapLayersByShortName ( const QString &  shortName ) const

inline

Retrieves a list of matching registered layers by layer shortName with a specified layer type, if layer's short name is empty a match with layer's name is attempted.

Parameters

shortName

short name of layers to match

Returns

list of matching layers

See also

mapLayer()

mapLayers()

Note

not available in Python bindings

Since

QGIS 3.10

Definition at line 1277 of file qgsproject.h.

mapScales()

QVector< double > QgsProject::mapScales

(

)

const

Returns the list of custom project map scales.

The scales list consists of a list of scale denominator values, e.g. 1000 for a 1:1000 scale.

See also

setMapScales()

mapScalesChanged()

Deprecated:

QGIS 3.40. Use viewSettings() instead.

Definition at line 5184 of file qgsproject.cpp.

mapScalesChanged

Q_DECL_DEPRECATED void QgsProject::mapScalesChanged ( )

signal

Emitted when the list of custom project map scales changes.

See also

mapScales()

setMapScales()

Deprecated:

QGIS 3.40. Use viewSettings() instead.

mapThemeCollection()

QgsMapThemeCollection * QgsProject::mapThemeCollection

(

)

Returns pointer to the project's map theme collection.

Note

renamed in QGIS 3.0, formerly QgsVisibilityPresetCollection

mapThemeCollectionChanged

void QgsProject::mapThemeCollectionChanged ( )

signal

Emitted when the map theme collection changes.

This only happens when the map theme collection is reset. Any pointer previously received from mapThemeCollection() must no longer be used after this signal is emitted. You must still connect to signals from the map theme collection if you want to be notified about new map themes being added and map themes being removed.

metadata()

const QgsProjectMetadata & QgsProject::metadata

(

)

const

Returns a reference to the project's metadata store.

See also

setMetadata()

metadataChanged()

Since

QGIS 3.2

Definition at line 5062 of file qgsproject.cpp.

metadataChanged

void QgsProject::metadataChanged ( )

signal

Emitted when the project's metadata is changed.

See also

setMetadata()

metadata()

Since

QGIS 3.2

missingDatumTransforms

void QgsProject::missingDatumTransforms ( const QStringList &  missingTransforms )

signal

Emitted when datum transforms stored in the project are not available locally.

nonIdentifiableLayers()

QStringList QgsProject::nonIdentifiableLayers

(

)

const

Gets the list of layers which currently should not be taken into account on map identification.

Deprecated:

QGIS 3.4. Use QgsMapLayer::setFlags() instead.

Definition at line 4447 of file qgsproject.cpp.

nonIdentifiableLayersChanged

Q_DECL_DEPRECATED void QgsProject::nonIdentifiableLayersChanged ( QStringList  nonIdentifiableLayers )

signal

Emitted when the list of layer which are excluded from map identification changes.

Deprecated:

QGIS 3.4

oldProjectVersionWarning

Q_DECL_DEPRECATED void QgsProject::oldProjectVersionWarning ( const QString &  warning )

signal

Emitted when an old project file is read.

Deprecated:

QGIS 3.40. Use readVersionMismatchOccurred() instead.

originalPath()

QString QgsProject::originalPath

(

)

const

Returns the original path associated with the project.

This is intended for use with non-qgs/qgz project files (see QgsCustomProjectOpenHandler) in order to allow custom project open handlers to specify the original file name of the project. For custom project formats, it is NOT appropriate to call setFileName() with the original project path, as this causes the original (non QGIS) project file to be overwritten when the project is next saved.

See also

setOriginalPath()

Since

QGIS 3.14

Definition at line 833 of file qgsproject.cpp.

pathResolver()

QgsPathResolver QgsProject::pathResolver

(

)

const

Returns path resolver object with considering whether the project uses absolute or relative paths and using current project's path.

Definition at line 3835 of file qgsproject.cpp.

presetHomePath()

QString QgsProject::presetHomePath

(

)

const

Returns any manual project home path setting, or an empty string if not set.

This path may be a relative path. See homePath() to retrieve a path which is always an absolute path.

See also

homePath()

setPresetHomePath()

homePathChanged()

Since

QGIS 3.2

Definition at line 4225 of file qgsproject.cpp.

projectColorsChanged

void QgsProject::projectColorsChanged ( )

signal

Emitted whenever the project's color scheme has been changed.

See also

setProjectColors()

Since

QGIS 3.6

projectSaved

void QgsProject::projectSaved ( )

signal

Emitted when the project file has been written and closed.

projectStorage()

QgsProjectStorage * QgsProject::projectStorage

(

)

const

Returns pointer to project storage implementation that handles read/write of the project file.

If the project file is stored in the local file system, returns nullptr. The project storage object is inferred from fileName() of the project.

Since

QGIS 3.2

Definition at line 847 of file qgsproject.cpp.

read() [1/2]

bool QgsProject::read	(	const QString &	filename,
		Qgis::ProjectReadFlags	flags = Qgis::ProjectReadFlags()
	)

Reads given project file from the given file.

Parameters

filename	name of project file to read
flags	optional flags which control the read behavior of projects

Returns

true if project file has been read successfully

Definition at line 1941 of file qgsproject.cpp.

read() [2/2]

bool QgsProject::read

(

Qgis::ProjectReadFlags

flags = Qgis::ProjectReadFlags()

)

Reads the project from its currently associated file (see fileName() ).

The flags argument can be used to specify optional flags which control the read behavior of projects.

Returns

true if project file has been read successfully

Definition at line 1952 of file qgsproject.cpp.

readBoolEntry()

bool QgsProject::readBoolEntry	(	const QString &	scope,
		const QString &	key,
		bool	def = false,
		bool *	ok = nullptr
	)		const

Reads a boolean from the specified scope and key.

Parameters

scope	entry scope (group) name
key	entry key name. Keys are '/'-delimited entries, implying a hierarchy of keys and corresponding values.
def	default value to return if the specified key does not exist within the scope.
ok	set to true if key exists and has been successfully retrieved as a boolean

Returns

entry value as boolean from scope given its key

Definition at line 3753 of file qgsproject.cpp.

readDoubleEntry()

double QgsProject::readDoubleEntry	(	const QString &	scope,
		const QString &	key,
		double	def = 0,
		bool *	ok = nullptr
	)		const

Reads a double from the specified scope and key.

Parameters

scope	entry scope (group) name
key	entry key name. Keys are '/'-delimited entries, implying a hierarchy of keys and corresponding values.
def	default value to return if the specified key does not exist within the scope.
ok	set to true if key exists and has been successfully retrieved as a double

Returns

entry value as double from scope given its key

Definition at line 3729 of file qgsproject.cpp.

readEntry()

QString QgsProject::readEntry	(	const QString &	scope,
		const QString &	key,
		const QString &	def = QString(),
		bool *	ok = nullptr
	)		const

Reads a string from the specified scope and key.

Parameters

scope	entry scope (group) name
key	entry key name. Keys are '/'-delimited entries, implying a hierarchy of keys and corresponding values.
def	default value to return if the specified key does not exist within the scope.
ok	set to true if key exists and has been successfully retrieved as a string value

Returns

entry value as string from scope given its key

Definition at line 3672 of file qgsproject.cpp.

readLayer()

bool QgsProject::readLayer

(

const QDomNode &

layerNode

)

Reads the layer described in the associated DOM node.

Note

This method is mainly for use by QgsProjectBadLayerHandler subclasses that may fix definition of bad layers with the user's help in GUI. Calling this method with corrected DOM node adds the layer back to the project.

Parameters

layerNode

represents a QgsProject DOM node that encodes a specific layer.

Definition at line 3091 of file qgsproject.cpp.

readListEntry()

QStringList QgsProject::readListEntry	(	const QString &	scope,
		const QString &	key,
		const QStringList &	def = QStringList(),
		bool *	ok = nullptr
	)		const

Reads a string list from the specified scope and key.

Parameters

scope	entry scope (group) name
key	entry key name. Keys are '/'-delimited entries, implying a hierarchy of keys and corresponding values.
def	default value to return if the specified key does not exist within the scope.
ok	set to true if key exists and has been successfully retrieved as a string list

Returns

entry value as a string list

Definition at line 3640 of file qgsproject.cpp.

readMapLayer

void QgsProject::readMapLayer ( QgsMapLayer *  mapLayer, const QDomElement &  layerNode  )

signal

Emitted after the basic initialization of a layer from the project file is done.

You can use this signal to read additional information from the project file.

Parameters

mapLayer	The map layer which is being initialized
layerNode	The layer node from the project file

readNumEntry()

int QgsProject::readNumEntry	(	const QString &	scope,
		const QString &	key,
		int	def = 0,
		bool *	ok = nullptr
	)		const

Reads an integer from the specified scope and key.

Parameters

scope	entry scope (group) name
key	entry key name. Keys are '/'-delimited entries, implying a hierarchy of keys and corresponding values.
def	default value to return if the specified key does not exist within the scope.
ok	set to true if key exists and has been successfully retrieved as an integer

Returns

entry value as integer from scope given its key

Definition at line 3700 of file qgsproject.cpp.

readPath()

QString QgsProject::readPath

(

const QString &

filename

)

const

Transforms a filename read from the project file to an absolute path.

Definition at line 3865 of file qgsproject.cpp.

readProject

void QgsProject::readProject ( const QDomDocument &  document )

signal

Emitted when a project is being read.

readProjectWithContext

void QgsProject::readProjectWithContext ( const QDomDocument &  document, QgsReadWriteContext &  context  )

signal

Emitted when a project is being read.

And passing the /a context

readVersionMismatchOccurred

void QgsProject::readVersionMismatchOccurred ( const QString &  fileVersion )

signal

Emitted when a project is read and the version of QGIS used to save the project differs from the current QGIS version.

The fileVersion argument indicates the version of QGIS used to save the project.

Note

Not available in Python bindings

Since

QGIS 3.26

registerTranslatableContainers

void QgsProject::registerTranslatableContainers ( QgsTranslationContext *  translationContext, QgsAttributeEditorContainer *  parent, const QString &  layerId  )

slot

Registers the containers that require translation into the translationContext.

This is a recursive function to get all the child containers.

Parameters

translationContext	where the objects will be registered
parent	parent-container containing list of children
layerId	to store under the correct context

Since

QGIS 3.4

Definition at line 634 of file qgsproject.cpp.

registerTranslatableObjects

void QgsProject::registerTranslatableObjects ( QgsTranslationContext *  translationContext )

slot

Registers the objects that require translation into the translationContext.

So there can be created a ts file with these values.

Since

QGIS 3.4

Definition at line 654 of file qgsproject.cpp.

relationManager()

QgsRelationManager * QgsProject::relationManager

(

)

const

Definition at line 4232 of file qgsproject.cpp.

reloadAllLayers()

void QgsProject::reloadAllLayers

(

)

Reload all registered layer's provider data caches, synchronising the layer with any changes in the datasource.

See also

QgsMapLayer::reload()

Definition at line 4870 of file qgsproject.cpp.

removeAll

void QgsProject::removeAll ( )

signal

Emitted when all layers are removed, before layersWillBeRemoved() and layerWillBeRemoved() signals are emitted.

The layersWillBeRemoved() and layerWillBeRemoved() signals will still be emitted following this signal. You can use this signal to do easy (and fast) cleanup.

removeAllMapLayers()

void QgsProject::removeAllMapLayers

(

)

Removes all registered layers.

If the registry has ownership of any layers these layers will also be deleted.

Note

As a side-effect the QgsProject instance is marked dirty.

Calling this method will cause the removeAll() signal to be emitted.

See also

removeMapLayer()

removeMapLayers()

Definition at line 4853 of file qgsproject.cpp.

removeAttachedFile()

bool QgsProject::removeAttachedFile

(

const QString &

path

)

Removes the attached file.

Parameters

path	Path to the attached file

Returns

Whether removal succeeded.

See also

createAttachedFile()

Since

QGIS 3.22

Definition at line 5037 of file qgsproject.cpp.

removeEntry()

bool QgsProject::removeEntry	(	const QString &	scope,
		const QString &	key
	)

Remove the given key from the specified scope.

Definition at line 3777 of file qgsproject.cpp.

removeMapLayer() [1/2]

void QgsProject::removeMapLayer

(

const QString &

layerId

)

Remove a layer from the registry by layer ID.

The specified layer will be removed from the registry. If the registry has ownership of the layer then it will also be deleted.

Parameters

layerId

ID of the layer to remove

Note

As a side-effect the QgsProject instance is marked dirty.

See also

removeMapLayers()

removeAllMapLayers()

Definition at line 4820 of file qgsproject.cpp.

removeMapLayer() [2/2]

void QgsProject::removeMapLayer

(

QgsMapLayer *

layer

)

Remove a layer from the registry.

The specified layer will be removed from the registry. If the registry has ownership of the layer then it will also be deleted.

Parameters

layer

The layer to remove. nullptr values are ignored.

Note

As a side-effect the QgsProject instance is marked dirty.

See also

removeMapLayers()

removeAllMapLayers()

Definition at line 4829 of file qgsproject.cpp.

removeMapLayers() [1/2]

void QgsProject::removeMapLayers

(

const QList< QgsMapLayer * > &

layers

)

Remove a set of layers from the registry.

The specified layers will be removed from the registry. If the registry has ownership of any layers these layers will also be deleted.

Parameters

layers

A list of layers to remove. nullptr values are ignored.

Note

As a side-effect the QgsProject instance is marked dirty.

See also

removeMapLayer()

removeAllMapLayers()

Definition at line 4809 of file qgsproject.cpp.

removeMapLayers() [2/2]

void QgsProject::removeMapLayers

(

const QStringList &

layerIds

)

Remove a set of layers from the registry by layer ID.

The specified layers will be removed from the registry. If the registry has ownership of any layers these layers will also be deleted.

Parameters

layerIds

list of IDs of the layers to remove

Note

As a side-effect the QgsProject instance is marked dirty.

See also

removeMapLayer()

removeAllMapLayers()

Definition at line 4798 of file qgsproject.cpp.

requiredLayers()

QSet< QgsMapLayer * > QgsProject::requiredLayers

(

)

const

Returns a set of map layers that are required in the project and therefore they should not get removed from the project.

The set of layers may be configured by users in project properties. and it is mainly a hint for the user interface to protect users from removing layers that important in the project. The removeMapLayer(), removeMapLayers() calls do not block removal of layers listed here.

Deprecated:

QGIS 3.4. Use QgsMapLayer::flags() instead.

Since

QGIS 3.2

Definition at line 5085 of file qgsproject.cpp.

resolveAttachmentIdentifier()

QString QgsProject::resolveAttachmentIdentifier

(

const QString &

identifier

)

const

Resolves an attachment identifier to a attachment file path.

Parameters

identifier

An attachment identifier

Returns

The attachment file path, or an empty string if the identifier is invalid

Since

QGIS 3.22

Definition at line 5051 of file qgsproject.cpp.

rollBack

bool QgsProject::rollBack ( QStringList &  rollbackErrors, bool  stopEditing = true, QgsVectorLayer *  vectorLayer = nullptr  )

slot

Stops a current editing operation on vectorLayer and discards any uncommitted edits.

Parameters

rollbackErrors	will be set to a list of descriptive errors if the rollback fails.
stopEditing	if set to false, the layer will stay in editing mode. Otherwise the layer editing mode will be disabled if the rollback is successful.
vectorLayer	for which the changes will be rolled back. For buffered transactions this parameter is not mandatory, as the changes from all layers will be rolled back.

Returns

true if the rollback was successful.

See also

startEditing()

commitChanges()

Since

QGIS 3.26

Definition at line 770 of file qgsproject.cpp.

saveUser()

QString QgsProject::saveUser

(

)

const

Returns the user name that did the last save.

See also

saveUserFullName()

Since

QGIS 3.12

Definition at line 566 of file qgsproject.cpp.

saveUserFullName()

QString QgsProject::saveUserFullName

(

)

const

Returns the full user name that did the last save.

See also

saveUser()

Since

QGIS 3.12

Definition at line 573 of file qgsproject.cpp.

selectionColor()

QColor QgsProject::selectionColor

(

)

const

Returns the color used to highlight selected features.

See also

setSelectionColor()

Since

QGIS 3.10

Definition at line 5170 of file qgsproject.cpp.

selectionColorChanged

void QgsProject::selectionColorChanged ( )

signal

Emitted whenever the project's selection color has been changed.

See also

setSelectionColor()

Since

QGIS 3.10

sensorManager() [1/2]

QgsSensorManager * QgsProject::sensorManager

(

)

Returns the project's sensor manager, which manages sensors within the project.

Since

QGIS 3.32

Definition at line 4289 of file qgsproject.cpp.

sensorManager() [2/2]

const QgsSensorManager * QgsProject::sensorManager

(

)

const

Returns the project's sensor manager, which manages sensors within the project.

Note

not available in Python bindings

Since

QGIS 3.32

Definition at line 4282 of file qgsproject.cpp.

setAreaUnits()

void QgsProject::setAreaUnits

(

Qgis::AreaUnit

unit

)

Sets the default area measurement units for the project.

See also

areaUnits()

setDistanceUnits()

Definition at line 4158 of file qgsproject.cpp.

setAutoTransaction()

void QgsProject::setAutoTransaction

(

bool

autoTransaction

)

Transactional editing means that on supported datasources (postgres databases) the edit state of all tables that originate from the same database are synchronized and executed in a server side transaction.

Warning

Make sure that this is only called when all layers are not in edit mode.

Deprecated:

QGIS 3.26. Use setTransactionMode instead.

Definition at line 4471 of file qgsproject.cpp.

setAvoidIntersectionsLayers()

void QgsProject::setAvoidIntersectionsLayers

(

const QList< QgsVectorLayer * > &

layers

)

Sets the list of layers with which intersections should be avoided.

Only used if the avoid intersection mode is set to advanced. Line and point layers will not be added.

Definition at line 2821 of file qgsproject.cpp.

setAvoidIntersectionsMode()

void QgsProject::setAvoidIntersectionsMode

(

const Qgis::AvoidIntersectionsMode

mode

)

Sets the avoid intersections mode.

Since

QGIS 3.14

Definition at line 1468 of file qgsproject.cpp.

setBackgroundColor()

void QgsProject::setBackgroundColor

(

const QColor &

color

)

Sets the default background color used by default map canvases.

See also

backgroundColor()

Since

QGIS 3.10

Definition at line 5141 of file qgsproject.cpp.

setBadLayerHandler()

void QgsProject::setBadLayerHandler

(

QgsProjectBadLayerHandler *

handler

)

Change handler for missing layers.

Deletes old handler and takes ownership of the new one.

Definition at line 3900 of file qgsproject.cpp.

setCrs()

void QgsProject::setCrs	(	const QgsCoordinateReferenceSystem &	crs,
		bool	adjustEllipsoid = false
	)

Sets the project's native coordinate reference system.

If adjustEllipsoid is set to true, the ellipsoid of this project will be set to the ellipsoid imposed by the CRS.

Changing the CRS will trigger a crsChanged() signal. Additionally, if crs is a compound CRS, then the verticalCrsChanged() signal will also be emitted.

See also

crs()

crsChanged()

setVerticalCrs()

setEllipsoid()

Definition at line 953 of file qgsproject.cpp.

setCustomVariables()

void QgsProject::setCustomVariables

(

const QVariantMap &

customVariables

)

A map of custom project variables.

Be careful not to set generated variables.

Definition at line 2749 of file qgsproject.cpp.

setDataDefinedServerProperties

void QgsProject::setDataDefinedServerProperties ( const QgsPropertyCollection &  properties )

slot

Sets the data defined properties used for overrides in user defined server parameters to properties.

Since

QGIS 3.14

Definition at line 709 of file qgsproject.cpp.

setDirty

void QgsProject::setDirty ( bool  b = true )

slot

Flag the project as dirty (modified).

If this flag is set, the user will be asked to save changes to the project before closing the current project.

Note

promoted to public slot in 2.16

Definition at line 601 of file qgsproject.cpp.

setDistanceUnits()

void QgsProject::setDistanceUnits

(

Qgis::DistanceUnit

unit

)

Sets the default distance measurement units for the project.

See also

distanceUnits()

setAreaUnits()

Definition at line 4146 of file qgsproject.cpp.

setElevationShadingRenderer()

void QgsProject::setElevationShadingRenderer

(

const QgsElevationShadingRenderer &

elevationShadingRenderer

)

Sets the elevation shading renderer used for global map shading.

Since

QGIS 3.30

Definition at line 4987 of file qgsproject.cpp.

setEllipsoid()

void QgsProject::setEllipsoid

(

const QString &

ellipsoid

)

Sets the project's ellipsoid from a proj string representation, e.g., "WGS84".

See also

ellipsoid()

setCrs()

setVerticalCrs()

Definition at line 996 of file qgsproject.cpp.

setEvaluateDefaultValues()

void QgsProject::setEvaluateDefaultValues

(

bool

evaluateDefaultValues

)

Defines if default values should be evaluated on provider side when requested and not when committed.

Deprecated:

QGIS 3.40. Use setFlag( Qgis::ProjectFlag::EvaluateDefaultValuesOnProviderSide ) instead.

Definition at line 4124 of file qgsproject.cpp.

setFileName()

void QgsProject::setFileName

(

const QString &

name

)

Sets the file name associated with the project.

This is the file or the storage URI which contains the project's XML representation.

Parameters

name	project file name

See also

fileName()

Definition at line 796 of file qgsproject.cpp.

setFilePathStorage()

void QgsProject::setFilePathStorage

(

Qgis::FilePathType

type

)

Sets the type of paths used when storing file paths in a QGS/QGZ project file.

See also

filePathStorage()

Since

QGIS 3.22

Definition at line 923 of file qgsproject.cpp.

setFlag()

void QgsProject::setFlag	(	Qgis::ProjectFlag	flag,
		bool	enabled = true
	)

Sets whether a project flag is enabled.

See also

flags()

setFlags()

Since

QGIS 3.26

Definition at line 554 of file qgsproject.cpp.

setFlags()

void QgsProject::setFlags

(

Qgis::ProjectFlags

flags

)

Sets the project's flags, which dictate the behavior of the project.

See also

flags()

setFlag()

Since

QGIS 3.26

Definition at line 516 of file qgsproject.cpp.

setInstance()

void QgsProject::setInstance ( QgsProject *  project )

static

Set the current project singleton instance to project.

Note

this method is provided mainly for the server, which caches the projects and (potentially) needs to switch the current instance on every request.

Warning

calling this method can have serious, unintended consequences, including instability, data loss and undefined behavior. Use with EXTREME caution!

See also

instance()

Since

QGIS 3.10.11

Definition at line 477 of file qgsproject.cpp.

setLabelingEngineSettings()

void QgsProject::setLabelingEngineSettings

(

const QgsLabelingEngineSettings &

settings

)

Sets project's global labeling engine settings.

Definition at line 2776 of file qgsproject.cpp.

setMapScales()

void QgsProject::setMapScales

(

const QVector< double > &

scales

)

Sets the list of custom project map scales.

The scales list consists of a list of scale denominator values, e.g. 1000 for a 1:1000 scale.

See also

mapScales()

mapScalesChanged()

Deprecated:

QGIS 3.40. Use viewSettings() instead.

Definition at line 5177 of file qgsproject.cpp.

setMetadata()

void QgsProject::setMetadata

(

const QgsProjectMetadata &

metadata

)

Sets the project's metadata store.

See also

metadata()

metadataChanged()

Since

QGIS 3.2

Definition at line 5070 of file qgsproject.cpp.

setNonIdentifiableLayers() [1/2]

void QgsProject::setNonIdentifiableLayers

(

const QList< QgsMapLayer * > &

layers

)

Set a list of layers which should not be taken into account on map identification.

Deprecated:

QGIS 3.4. Use QgsMapLayer::setFlags() instead.

Definition at line 4409 of file qgsproject.cpp.

setNonIdentifiableLayers() [2/2]

void QgsProject::setNonIdentifiableLayers

(

const QStringList &

layerIds

)

Set a list of layers which should not be taken into account on map identification.

Deprecated:

QGIS 3.4. Use QgsMapLayer::setFlags() instead.

Definition at line 4430 of file qgsproject.cpp.

setOriginalPath()

void QgsProject::setOriginalPath

(

const QString &

path

)

Sets the original path associated with the project.

This is intended for use with non-qgs/qgz project files (see QgsCustomProjectOpenHandler) in order to allow custom project open handlers to specify the original file name of the project. For custom project formats, it is NOT appropriate to call setFileName() with the original project path, as this causes the original (non QGIS) project file to be overwritten when the project is next saved.

See also

originalPath()

Since

QGIS 3.14

Definition at line 826 of file qgsproject.cpp.

setPresetHomePath

void QgsProject::setPresetHomePath ( const QString &  path )

slot

Sets the project's home path.

If an empty path is specified than the home path will be automatically determined from the project's file path.

See also

presetHomePath()

homePath()

homePathChanged()

Since

QGIS 3.2

Definition at line 618 of file qgsproject.cpp.

setProjectColors()

void QgsProject::setProjectColors

(

const QgsNamedColorList &

colors

)

Sets the colors for the project's color scheme (see QgsProjectColorScheme).

See also

projectColorsChanged()

Since

QGIS 3.6

Definition at line 5119 of file qgsproject.cpp.

setRequiredLayers()

void QgsProject::setRequiredLayers

(

const QSet< QgsMapLayer * > &

layers

)

Configures a set of map layers that are required in the project and therefore they should not get removed from the project.

The set of layers may be configured by users in project properties. and it is mainly a hint for the user interface to protect users from removing layers that important in the project. The removeMapLayer(), removeMapLayers() calls do not block removal of layers listed here.

Deprecated:

QGIS 3.4. Use QgsMapLayer::setFlags() instead.

Since

QGIS 3.2

Definition at line 5102 of file qgsproject.cpp.

setSelectionColor()

void QgsProject::setSelectionColor

(

const QColor &

color

)

Sets the color used to highlight selected features.

See also

selectionColor()

Since

QGIS 3.10

Definition at line 5159 of file qgsproject.cpp.

setSnappingConfig

void QgsProject::setSnappingConfig ( const QgsSnappingConfig &  snappingConfig )

slot

The snapping configuration for this project.

Definition at line 1456 of file qgsproject.cpp.

setTitle()

void QgsProject::setTitle

(

const QString &

title

)

Sets the project's title.

Parameters

title

new title

Note

Since QGIS 3.2 this is just a shortcut to setting the title in the project's metadata().

See also

title()

Definition at line 494 of file qgsproject.cpp.

setTopologicalEditing()

void QgsProject::setTopologicalEditing

(

bool

enabled

)

Convenience function to set topological editing.

Definition at line 4131 of file qgsproject.cpp.

setTransactionMode()

bool QgsProject::setTransactionMode

(

Qgis::TransactionMode

transactionMode

)

Set transaction mode.

Returns

true if the transaction mode could be changed

Note

Transaction mode can be changed only when all layers are not in edit mode.

See also

Qgis::TransactionMode

Since

QGIS 3.26

Definition at line 4498 of file qgsproject.cpp.

setTransformContext()

void QgsProject::setTransformContext

(

const QgsCoordinateTransformContext &

context

)

Sets the project's coordinate transform context, which stores various information regarding which datum transforms should be used when transforming points from a source to destination coordinate reference system.

See also

transformContext()

transformContextChanged()

Definition at line 1146 of file qgsproject.cpp.

setTrustLayerMetadata()

void QgsProject::setTrustLayerMetadata

(

bool

trust

)

Sets the trust option allowing to indicate if the extent has to be read from the XML document when data source has no metadata or if the data provider has to determine it.

Moreover, when this option is activated, primary key unicity is not checked for views and materialized views with Postgres provider.

Parameters

trust

true to trust the project, false otherwise

Deprecated:

QGIS 3.40. Use setFlag( Qgis::ProjectFlag::TrustStoredLayerStatistics ) instead.

Definition at line 4928 of file qgsproject.cpp.

setUseProjectScales()

void QgsProject::setUseProjectScales

(

bool

enabled

)

Sets whether project mapScales() are enabled.

See also

useProjectScales()

setMapScales()

Deprecated:

QGIS 3.40. Use viewSettings() instead.

Definition at line 5191 of file qgsproject.cpp.

setVerticalCrs()

bool QgsProject::setVerticalCrs	(	const QgsCoordinateReferenceSystem &	crs,
		QString *	errorMessage = nullptr
	)

Sets the project's vertical coordinate reference system.

The verticalCrsChanged() signal will be raised if the vertical CRS is changed.

Note

If the project crs() is a compound CRS, then the CRS returned for verticalCrs() will be the vertical component of crs(). Otherwise it will be the value explicitly set by this call.

Parameters

crs	the vertical CRS
errorMessage	will be set to a descriptive message if the vertical CRS could not be set

Returns

true if vertical CRS was successfully set

See also

verticalCrs()

setCrs()

Since

QGIS 3.38

Definition at line 1038 of file qgsproject.cpp.

snappingConfig()

QgsSnappingConfig QgsProject::snappingConfig

(

)

const

The snapping configuration for this project.

Definition at line 1449 of file qgsproject.cpp.

snappingConfigChanged

void QgsProject::snappingConfigChanged ( const QgsSnappingConfig &  config )

signal

Emitted whenever the configuration for snapping has changed.

startEditing

bool QgsProject::startEditing ( QgsVectorLayer *  vectorLayer = nullptr )

slot

Makes the layer editable.

This starts an edit session on vectorLayer. Changes made in this edit session will not be made persistent until commitChanges() is called, and can be reverted by calling rollBack().

Returns

true if the layer was successfully made editable, or false if the operation failed (e.g. due to an underlying read-only data source, or lack of edit support by the backend data provider).

See also

commitChanges()

rollBack()

Since

QGIS 3.26

Definition at line 723 of file qgsproject.cpp.

styleSettings() [1/2]

QgsProjectStyleSettings * QgsProject::styleSettings

(

)

Returns the project's style settings, which contains settings and properties relating to how a QgsProject should handle styling.

(e.g. styling of a newly added vector layer)

Since

QGIS 3.26

Definition at line 4317 of file qgsproject.cpp.

styleSettings() [2/2]

const QgsProjectStyleSettings * QgsProject::styleSettings

(

)

const

Returns the project's style settings, which contains settings and properties relating to how a QgsProject should handle styling.

(e.g. styling of a newly added vector layer)

Note

not available in Python bindings

Since

QGIS 3.26

Definition at line 4310 of file qgsproject.cpp.

subkeyList()

QStringList QgsProject::subkeyList	(	const QString &	scope,
		const QString &	key
	)		const

Returns a list of child keys which contain other keys that exist within the the specified scope and key.

This method only returns keys with keys, it will not return keys that contain only values. See entryList() to retrieve keys with values.

Note

equivalent to QgsSettings subkeyList()

Definition at line 3809 of file qgsproject.cpp.

takeMapLayer()

QgsMapLayer * QgsProject::takeMapLayer

(

QgsMapLayer *

layer

)

Takes a layer from the registry.

If the layer was owned by the project, the layer will be returned without deleting it. The caller takes ownership of the layer and is responsible for deleting it.

See also

removeMapLayer()

Definition at line 4838 of file qgsproject.cpp.

timeSettings() [1/2]

QgsProjectTimeSettings * QgsProject::timeSettings

(

)

Returns the project's time settings, which contains the project's temporal range and other time based settings.

Since

QGIS 3.14

Definition at line 4332 of file qgsproject.cpp.

timeSettings() [2/2]

const QgsProjectTimeSettings * QgsProject::timeSettings

(

)

const

Returns the project's time settings, which contains the project's temporal range and other time based settings.

Note

not available in Python bindings

Since

QGIS 3.14

Definition at line 4325 of file qgsproject.cpp.

title()

QString QgsProject::title

(

)

const

Returns the project's title.

See also

setTitle()

Note

Since QGIS 3.2 this is just a shortcut to retrieving the title from the project's metadata().

Definition at line 508 of file qgsproject.cpp.

topologicalEditing()

bool QgsProject::topologicalEditing

(

)

const

Convenience function to query topological editing status.

Definition at line 4139 of file qgsproject.cpp.

topologicalEditingChanged

void QgsProject::topologicalEditingChanged ( )

signal

Emitted when the topological editing flag has changed.

transactionGroup()

QgsTransactionGroup * QgsProject::transactionGroup	(	const QString &	providerKey,
		const QString &	connString
	)

Returns the matching transaction group from a provider key and connection string.

Returns nullptr if a matching transaction group is not available.

Since

QGIS 3.2

Definition at line 4890 of file qgsproject.cpp.

transactionGroups()

QMap< QPair< QString, QString >, QgsTransactionGroup * > QgsProject::transactionGroups

(

)

Map of transaction groups.

QPair( providerKey, connString ) -> transactionGroup

Note

Not available in Python bindings

Definition at line 4522 of file qgsproject.cpp.

transactionGroupsChanged

void QgsProject::transactionGroupsChanged ( )

signal

Emitted whenever a new transaction group has been created or a transaction group has been removed.

transactionMode()

Qgis::TransactionMode QgsProject::transactionMode

(

)

const

Returns the transaction mode.

See also

Qgis::TransactionMode

Since

QGIS 3.26

Definition at line 4491 of file qgsproject.cpp.

transactionModeChanged

void QgsProject::transactionModeChanged ( )

signal

Emitted when the transaction mode has changed.

Since

QGIS 3.38

transformContext()

QgsCoordinateTransformContext QgsProject::transformContext

(

)

const

Returns a copy of the project's coordinate transform context, which stores various information regarding which datum transforms should be used when transforming points from a source to destination coordinate reference system.

See also

setTransformContext()

transformContextChanged()

Definition at line 1138 of file qgsproject.cpp.

transformContextChanged

void QgsProject::transformContextChanged ( )

signal

Emitted when the project transformContext() is changed.

See also

transformContext()

translate()

QString QgsProject::translate ( const QString &  context, const QString &  sourceText, const char *  disambiguation = nullptr, int  n = -1  ) const

overridevirtual

Translates a string using the Qt QTranslator mechanism.

This function can be called from wherever the QgsReadWriteContext is available.

Parameters

context	describes the context of the translation, eg the corresponding map layer
sourceText	the identifier of the text to translate (usually the original untranslated string)
disambiguation	optional string providing additional context for the translation
n	optional "object count", which can alter the translation to account for plural forms

Returns

the translated string. In the case that there is no QTranslator available, the sourceText will be returned unchanged.

Since

QGIS 3.4

Implements QgsProjectTranslator.

Definition at line 5218 of file qgsproject.cpp.

trustLayerMetadata()

bool QgsProject::trustLayerMetadata

(

)

const

Returns true if the trust option is activated, false otherwise.

This option allows indicateing if the extent has to be read from the XML document when data source has no metadata or if the data provider has to determine it. Moreover, when this option is activated, primary key unicity is not checked for views and materialized views with Postgres provider.

Deprecated:

QGIS 3.40. Test whether the flags() method returns the Qgis::ProjectFlag::TrustStoredLayerStatistics flag instead.

Definition at line 4935 of file qgsproject.cpp.

useProjectScales()

bool QgsProject::useProjectScales

(

)

const

Returns true if project mapScales() are enabled.

See also

setUseProjectScales()

mapScales()

Deprecated:

QGIS 3.40. Use viewSettings() instead.

Definition at line 5198 of file qgsproject.cpp.

validCount()

int QgsProject::validCount

(

)

const

Returns the number of registered valid layers.

Definition at line 4542 of file qgsproject.cpp.

verticalCrs()

QgsCoordinateReferenceSystem QgsProject::verticalCrs

(

)

const

Returns the project's vertical coordinate reference system.

If the project crs() is a compound CRS, then the CRS returned will be the vertical component of crs(). Otherwise it will be the value explicitly set by a call to setVerticalCrs().

The returned CRS will be invalid if the project has no vertical CRS.

Note

Consider also using crs3D(), which will return a CRS which takes into account both crs() and verticalCrs().

See also

crs()

crs3D()

setVerticalCrs()

Since

QGIS 3.38

Definition at line 1008 of file qgsproject.cpp.

verticalCrsChanged

void QgsProject::verticalCrsChanged ( )

signal

Emitted when the verticalCrs() of the project has changed.

This signal will be emitted whenever the vertical CRS of the project is changed, either as a direct result of a call to setVerticalCrs() or when setCrs() is called with a compound CRS.

See also

crsChanged()

crs3DChanged()

setCrs()

setVerticalCrs()

verticalCrs()

Since

QGIS 3.38

viewSettings() [1/2]

QgsProjectViewSettings * QgsProject::viewSettings

(

)

Returns the project's view settings, which contains settings and properties relating to how a QgsProject should be viewed and behave inside a map canvas (e.g.

map scales and default view extent)

Since

QGIS 3.10.1

Definition at line 4303 of file qgsproject.cpp.

viewSettings() [2/2]

const QgsProjectViewSettings * QgsProject::viewSettings

(

)

const

Returns the project's view settings, which contains settings and properties relating to how a QgsProject should be viewed and behave inside a map canvas (e.g.

map scales and default view extent)

Note

not available in Python bindings

Since

QGIS 3.10.1

Definition at line 4296 of file qgsproject.cpp.

viewsManager() [1/2]

QgsMapViewsManager * QgsProject::viewsManager

(

)

Returns the project's views manager, which manages map views (including 3d maps) in the project.

Since

QGIS 3.24

Definition at line 4261 of file qgsproject.cpp.

viewsManager() [2/2]

const QgsMapViewsManager * QgsProject::viewsManager

(

)

const

Returns the project's views manager, which manages map views (including 3d maps) in the project.

Note

not available in Python bindings

Since

QGIS 3.24

Definition at line 4254 of file qgsproject.cpp.

write() [1/2]

bool QgsProject::write

(

)

Writes the project to its current associated file (see fileName() ).

Returns

true if project was written successfully

Note

isDirty() will be set to false if project is successfully written

Definition at line 3130 of file qgsproject.cpp.

write() [2/2]

bool QgsProject::write

(

const QString &

filename

)

Writes the project to a file.

Parameters

filename

destination file

Returns

true if project was written successfully

Note

calling this implicitly sets the project's filename (see setFileName() )

isDirty() will be set to false if project is successfully written

Definition at line 3121 of file qgsproject.cpp.

writeEntry() [1/5]

bool QgsProject::writeEntry	(	const QString &	scope,
		const QString &	key,
		bool	value
	)

Write a boolean value to the project file.

Keys are '/'-delimited entries, implying a hierarchy of keys and corresponding values

Note

The key string must be valid xml tag names in order to be saved to the file.

available in Python bindings as writeEntryBool

See also

readBoolEntry()

Definition at line 3575 of file qgsproject.cpp.

writeEntry() [2/5]

bool QgsProject::writeEntry	(	const QString &	scope,
		const QString &	key,
		const QString &	value
	)

Write a string value to the project file.

Keys are '/'-delimited entries, implying a hierarchy of keys and corresponding values

Note

The key string must be valid xml tag names in order to be saved to the file.

See also

readEntry()

Definition at line 3614 of file qgsproject.cpp.

writeEntry() [3/5]

bool QgsProject::writeEntry	(	const QString &	scope,
		const QString &	key,
		const QStringList &	value
	)

Write a string list value to the project file.

Keys are '/'-delimited entries, implying a hierarchy of keys and corresponding values

Note

The key string must be valid xml tag names in order to be saved to the file.

See also

readListEntry()

Definition at line 3627 of file qgsproject.cpp.

writeEntry() [4/5]

bool QgsProject::writeEntry	(	const QString &	scope,
		const QString &	key,
		double	value
	)

Write a double value to the project file.

Keys are '/'-delimited entries, implying a hierarchy of keys and corresponding values

Note

The key string must be valid xml tag names in order to be saved to the file.

available in Python bindings as writeEntryDouble

See also

readDoubleEntry()

Definition at line 3588 of file qgsproject.cpp.

writeEntry() [5/5]

bool QgsProject::writeEntry	(	const QString &	scope,
		const QString &	key,
		int	value
	)

Write an integer value to the project file.

Keys are '/'-delimited entries, implying a hierarchy of keys and corresponding values

Note

The key string must be valid xml tag names in order to be saved to the file.

See also

readNumEntry()

Definition at line 3601 of file qgsproject.cpp.

writeMapLayer

void QgsProject::writeMapLayer ( QgsMapLayer *  mapLayer, QDomElement &  layerElem, QDomDocument &  doc  )

signal

Emitted when a layer is being saved.

You can use this method to save additional information to the layer.

Parameters

mapLayer	The map layer which is being initialized
layerElem	The layer element from the project file
doc	The document

writePath()

QString QgsProject::writePath

(

const QString &

filename

)

const

Prepare a filename to save it to the project file.

Creates an absolute or relative path according to the project settings. Paths written to the project file should be prepared with this method.

Definition at line 3872 of file qgsproject.cpp.

writeProject

void QgsProject::writeProject ( QDomDocument &  document )

signal

Emitted when the project is being written.

Friends And Related Symbol Documentation

QgsApplication

friend class QgsApplication

friend

Definition at line 2492 of file qgsproject.h.

QgsProjectDirtyBlocker

friend class QgsProjectDirtyBlocker

friend

Definition at line 2494 of file qgsproject.h.

QgsProviderRegistry

friend class QgsProviderRegistry

friend

Definition at line 2497 of file qgsproject.h.

QgsServer

friend class QgsServer

friend

Definition at line 2500 of file qgsproject.h.

TestQgsProject

friend class TestQgsProject

friend

Definition at line 2502 of file qgsproject.h.

Property Documentation

areaUnits

Qgis::AreaUnit QgsProject::areaUnits

readwrite

Definition at line 125 of file qgsproject.h.

avoidIntersectionsLayers

QList<QgsVectorLayer *> QgsProject::avoidIntersectionsLayers

readwrite

Definition at line 119 of file qgsproject.h.

avoidIntersectionsMode

Qgis::AvoidIntersectionsMode QgsProject::avoidIntersectionsMode

readwrite

Definition at line 118 of file qgsproject.h.

backgroundColor

QColor QgsProject::backgroundColor

readwrite

Definition at line 121 of file qgsproject.h.

crs

QgsCoordinateReferenceSystem QgsProject::crs

readwrite

Definition at line 112 of file qgsproject.h.

displaySettings

QgsProjectDisplaySettings * QgsProject::displaySettings

read

Definition at line 126 of file qgsproject.h.

distanceUnits

Qgis::DistanceUnit QgsProject::distanceUnits

readwrite

Definition at line 124 of file qgsproject.h.

ellipsoid

QString QgsProject::ellipsoid

readwrite

Definition at line 114 of file qgsproject.h.

fileName

QString QgsProject::fileName

readwrite

Definition at line 110 of file qgsproject.h.

homePath

QString QgsProject::homePath

readwrite

Definition at line 111 of file qgsproject.h.

mapThemeCollection

QgsMapThemeCollection * QgsProject::mapThemeCollection

read

Definition at line 115 of file qgsproject.h.

metadata

QgsProjectMetadata QgsProject::metadata

readwrite

Definition at line 120 of file qgsproject.h.

nonIdentifiableLayers

QStringList QgsProject::nonIdentifiableLayers

readwrite

Definition at line 109 of file qgsproject.h.

relationManager

QgsRelationManager * QgsProject::relationManager

read

Definition at line 117 of file qgsproject.h.

selectionColor

QColor QgsProject::selectionColor

readwrite

Definition at line 122 of file qgsproject.h.

snappingConfig

QgsSnappingConfig QgsProject::snappingConfig

readwrite

Definition at line 116 of file qgsproject.h.

topologicalEditing

bool QgsProject::topologicalEditing

readwrite

Definition at line 123 of file qgsproject.h.

transactionMode

Qgis::TransactionMode QgsProject::transactionMode

readwrite

Definition at line 127 of file qgsproject.h.

transformContext

QgsCoordinateTransformContext QgsProject::transformContext

readwrite

Definition at line 113 of file qgsproject.h.

---

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

• /build/qgis-3.41.0+git20241110+fda2aa46e9a+99sid/src/core/project/qgsproject.h
• /build/qgis-3.41.0+git20241110+fda2aa46e9a+99sid/src/core/project/qgsproject.cpp