QGIS API Documentation  3.5.0-Master (591bb75)
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QgsProject Class Reference

Reads and writes project states. More...

#include <qgsproject.h>

Inheritance diagram for QgsProject:
Inheritance graph
[legend]

Public Slots

void registerTranslatableContainers (QgsTranslationContext *translationContext, QgsAttributeEditorContainer *parent, const QString &layerId)
 Registers the containers that require translation into the translationContext. More...
 
void registerTranslatableObjects (QgsTranslationContext *translationContext)
 Registers the objects that require translation into the translationContext. More...
 
void setDirty (bool b=true)
 Flag the project as dirty (modified). More...
 
void setPresetHomePath (const QString &path)
 Sets the project's home path. More...
 
void setSnappingConfig (const QgsSnappingConfig &snappingConfig)
 The snapping configuration for this project. More...
 

Signals

void avoidIntersectionsLayersChanged ()
 Emitted whenever avoidIntersectionsLayers has changed. More...
 
void cleared ()
 Emitted when the project is cleared (and additionally when an open project is cleared just before a new project is read). More...
 
void crsChanged ()
 Emitted when the CRS of the project has changed. More...
 
void customVariablesChanged ()
 Emitted whenever the expression variables stored in the project have been changed. More...
 
void ellipsoidChanged (const QString &ellipsoid)
 Emitted when the project ellipsoid is changed. More...
 
void fileNameChanged ()
 Emitted when the file name of the project changes. More...
 
void homePathChanged ()
 Emitted when the home path of the project changes. More...
 
void isDirtyChanged (bool dirty)
 Emitted when the project dirty status changes. More...
 
void labelingEngineSettingsChanged ()
 Emitted when global configuration of the labeling engine changes. More...
 
void layerLoaded (int i, int n)
 Emitted when a layer from a projects was read. More...
 
void layerRemoved (const QString &layerId)
 Emitted after a layer was removed from the registry. More...
 
void layersAdded (const QList< QgsMapLayer *> &layers)
 Emitted when one or more layers were added to the registry. More...
 
void layersRemoved (const QStringList &layerIds)
 Emitted after one or more layers were removed from the registry. More...
 
void layersWillBeRemoved (const QStringList &layerIds)
 Emitted when one or more layers are about to be removed from the registry. More...
 
void layersWillBeRemoved (const QList< QgsMapLayer *> &layers)
 Emitted when one or more layers are about to be removed from the registry. More...
 
void layerWasAdded (QgsMapLayer *layer)
 Emitted when a layer was added to the registry. More...
 
void layerWillBeRemoved (const QString &layerId)
 Emitted when a layer is about to be removed from the registry. More...
 
void layerWillBeRemoved (QgsMapLayer *layer)
 Emitted when a layer is about to be removed from the registry. More...
 
void legendLayersAdded (const QList< QgsMapLayer *> &layers)
 Emitted, when a layer was added to the registry and the legend. More...
 
void loadingLayer (const QString &layerName)
 Emitted when a layer is loaded. More...
 
void loadingLayerMessageReceived (const QString &layerName, const QList< QgsReadWriteContext::ReadWriteMessage > &messages)
 Emitted when loading layers has produced some messages. More...
 
void mapThemeCollectionChanged ()
 Emitted when the map theme collection changes. More...
 
void metadataChanged ()
 Emitted when the project's metadata is changed. More...
 
void missingDatumTransforms (const QStringList &missingTransforms)
 Emitted when datum transforms stored in the project are not available locally. More...
 
Q_DECL_DEPRECATED void nonIdentifiableLayersChanged (QStringList nonIdentifiableLayers)
 Emitted when the list of layer which are excluded from map identification changes. More...
 
void oldProjectVersionWarning (const QString &)
 Emitted when an old project file is read. More...
 
void projectSaved ()
 Emitted when the project file has been written and closed. More...
 
void readMapLayer (QgsMapLayer *mapLayer, const QDomElement &layerNode)
 Emitted after the basic initialization of a layer from the project file is done. More...
 
void readProject (const QDomDocument &)
 Emitted when a project is being read. More...
 
void readProjectWithContext (const QDomDocument &, QgsReadWriteContext &context)
 Emitted when a project is being read. More...
 
void removeAll ()
 Emitted when all layers are removed, before layersWillBeRemoved() and layerWillBeRemoved() signals are emitted. More...
 
void snappingConfigChanged (const QgsSnappingConfig &config)
 Emitted whenever the configuration for snapping has changed. More...
 
void topologicalEditingChanged ()
 Emitted when the topological editing flag has changed. More...
 
void transactionGroupsChanged ()
 Emitted whenever a new transaction group has been created or a transaction group has been removed. More...
 
void transformContextChanged ()
 Emitted when the project transformContext() is changed. More...
 
void writeMapLayer (QgsMapLayer *mapLayer, QDomElement &layerElem, QDomDocument &doc)
 Emitted when a layer is being saved. More...
 
void writeProject (QDomDocument &)
 Emitted when the project is being written. More...
 

Public Member Functions

 QgsProject (QObject *parent=nullptr)
 Create a new QgsProject. More...
 
 ~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(). More...
 
QString absolutePath () const
 Returns full absolute path to the project folder if the project is stored in a file system - derived from fileName(). More...
 
QgsMapLayeraddMapLayer (QgsMapLayer *mapLayer, bool addToLegend=true, bool takeOwnership=true)
 Add a layer to the map of loaded layers. More...
 
QList< QgsMapLayer * > addMapLayers (const QList< QgsMapLayer *> &mapLayers, bool addToLegend=true, bool takeOwnership=true)
 Add a list of layers to the map of loaded layers. More...
 
QgsAnnotationManagerannotationManager ()
 Returns pointer to the project's annotation manager. More...
 
const QgsAnnotationManagerannotationManager () const
 Returns a const pointer to the project's annotation manager. More...
 
QgsUnitTypes::AreaUnit areaUnits () const
 Convenience function to query default area measurement units for project. More...
 
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. More...
 
const QgsAuxiliaryStorageauxiliaryStorage () const
 Returns the current const auxiliary storage. More...
 
QgsAuxiliaryStorageauxiliaryStorage ()
 Returns the current auxiliary storage. More...
 
QList< QgsVectorLayer * > avoidIntersectionsLayers () const
 A list of layers with which intersections should be avoided. More...
 
QString baseName () const
 Returns the base name of the project file without the path and without extension - derived from fileName(). More...
 
void clear ()
 Clears the project, removing all settings and resetting it back to an empty, default state. More...
 
int count () const
 Returns the number of registered layers. More...
 
QgsLayerTreeGroupcreateEmbeddedGroup (const QString &groupName, const QString &projectFilePath, const QStringList &invisibleLayers)
 Create layer group instance defined in an arbitrary project file. More...
 
bool createEmbeddedLayer (const QString &layerId, const QString &projectFilePath, QList< QDomNode > &brokenNodes, bool saveFlag=true)
 Creates a maplayer instance defined in an arbitrary project file. More...
 
QgsExpressionContext createExpressionContext () const override
 This method needs to be reimplemented in all classes which implement this interface and return an expression context. More...
 
QgsCoordinateReferenceSystem crs () const
 Returns the project's native coordinate reference system. More...
 
QVariantMap customVariables () const
 A map of custom project variables. More...
 
QgsCoordinateReferenceSystem defaultCrsForNewLayers () const
 Returns the default CRS for new layers based on the settings and the current project CRS. More...
 
QgsUnitTypes::DistanceUnit distanceUnits () const
 Convenience function to query default distance measurement units for project. More...
 
void dumpProperties () const
 Dump out current project properties to stderr. More...
 
QString ellipsoid () const
 Returns a proj string representing the project's ellipsoid setting, e.g., "WGS84". More...
 
QStringList entryList (const QString &scope, const QString &key) const
 Returns keys with values – do not return keys that contain other keys. More...
 
QString error () const
 Returns error message from previous read/write. More...
 
bool evaluateDefaultValues () const
 Should default values be evaluated on provider side when requested and not when committed. More...
 
Q_DECL_DEPRECATED QFileInfo fileInfo () const
 Returns QFileInfo object for the project's associated file. More...
 
QString fileName () const
 Returns the project's file name. More...
 
void generateTsFile (const QString &locale)
 Triggers the collection strings of .qgs to be included in ts file and calls writeTsFile() More...
 
QString homePath () const
 Returns the project's home path. More...
 
bool isDirty () const
 Returns true if the project has been modified since the last write() More...
 
bool isZipped () const
 Returns true if the project comes from a zip archive, false otherwise. More...
 
const QgsLabelingEngineSettingslabelingEngineSettings () const
 Returns project's global labeling engine settings. More...
 
QDateTime lastModified () const
 Returns last modified time of the project file as returned by the file system (or other project storage). More...
 
QString layerIsEmbedded (const QString &id) const
 Returns project file path if layer is embedded from other project file. Returns empty string if layer is not embedded. More...
 
template<typename T >
QVector< T > layers () const
 Returns a list of registered map layers with a specified layer type. More...
 
QgsMapLayerStorelayerStore ()
 Returns a pointer to the project's internal layer store. More...
 
const QgsMapLayerStorelayerStore () const
 Returns a pointer to the project's internal layer store. More...
 
QgsLayerTreeRegistryBridgelayerTreeRegistryBridge () const
 Returns pointer to the helper class that synchronizes map layer registry with layer tree. More...
 
QgsLayerTreelayerTreeRoot () const
 Returns pointer to the root (invisible) node of the project's layer tree. More...
 
const QgsLayoutManagerlayoutManager () const
 Returns the project's layout manager, which manages compositions within the project. More...
 
QgsLayoutManagerlayoutManager ()
 Returns the project's layout manager, which manages compositions within the project. More...
 
QgsMapLayermapLayer (const QString &layerId) const
 Retrieve a pointer to a registered layer by layer ID. More...
 
QMap< QString, QgsMapLayer * > mapLayers (const bool validOnly=false) const
 Returns a map of all registered layers by layer ID. More...
 
QList< QgsMapLayer * > mapLayersByName (const QString &layerName) const
 Retrieve a list of matching registered layers by layer name. More...
 
QgsMapThemeCollectionmapThemeCollection ()
 Returns pointer to the project's map theme collection. More...
 
const QgsProjectMetadatametadata () const
 Returns a reference to the project's metadata store. More...
 
Q_DECL_DEPRECATED QStringList nonIdentifiableLayers () const
 Gets the list of layers which currently should not be taken into account on map identification. More...
 
QgsPathResolver pathResolver () const
 Returns path resolver object with considering whether the project uses absolute or relative paths and using current project's path. More...
 
QString presetHomePath () const
 Returns any manual project home path setting, or an empty string if not set. More...
 
QgsProjectStorageprojectStorage () const
 Returns pointer to project storage implementation that handles read/write of the project file. More...
 
bool read (const QString &filename)
 Reads given project file from the given file. More...
 
bool read ()
 Reads the project from its currently associated file (see fileName() ). More...
 
bool readBoolEntry (const QString &scope, const QString &key, bool def=false, bool *ok=nullptr) const
 
double readDoubleEntry (const QString &scope, const QString &key, double def=0, bool *ok=nullptr) const
 
QString readEntry (const QString &scope, const QString &key, const QString &def=QString(), bool *ok=nullptr) const
 
bool readLayer (const QDomNode &layerNode)
 Reads the layer described in the associated DOM node. More...
 
QStringList readListEntry (const QString &scope, const QString &key, const QStringList &def=QStringList(), bool *ok=nullptr) const
 Key value accessors. More...
 
int readNumEntry (const QString &scope, const QString &key, int def=0, bool *ok=nullptr) const
 
QString readPath (const QString &filename) const
 Turn filename read from the project file to an absolute path. More...
 
QgsRelationManagerrelationManager () const
 
void reloadAllLayers ()
 Reload all registered layer's provider data caches, synchronising the layer with any changes in the datasource. More...
 
void removeAllMapLayers ()
 Removes all registered layers. More...
 
bool removeEntry (const QString &scope, const QString &key)
 Remove the given key. More...
 
void removeMapLayer (const QString &layerId)
 Remove a layer from the registry by layer ID. More...
 
void removeMapLayer (QgsMapLayer *layer)
 Remove a layer from the registry. More...
 
void removeMapLayers (const QStringList &layerIds)
 Remove a set of layers from the registry by layer ID. More...
 
void removeMapLayers (const QList< QgsMapLayer *> &layers)
 Remove a set of layers from the registry. More...
 
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. More...
 
void setAreaUnits (QgsUnitTypes::AreaUnit unit)
 Sets the default area measurement units for the project. More...
 
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. More...
 
void setAvoidIntersectionsLayers (const QList< QgsVectorLayer *> &layers)
 A list of layers with which intersections should be avoided. More...
 
void setBadLayerHandler (QgsProjectBadLayerHandler *handler)
 Change handler for missing layers. More...
 
void setCrs (const QgsCoordinateReferenceSystem &crs)
 Sets the project's native coordinate reference system. More...
 
void setCustomVariables (const QVariantMap &customVariables)
 A map of custom project variables. More...
 
void setDistanceUnits (QgsUnitTypes::DistanceUnit unit)
 Sets the default distance measurement units for the project. More...
 
void setEllipsoid (const QString &ellipsoid)
 Sets the project's ellipsoid from a proj string representation, e.g., "WGS84". More...
 
void setEvaluateDefaultValues (bool evaluateDefaultValues)
 Defines if default values should be evaluated on provider side when requested and not when committed. More...
 
void setFileName (const QString &name)
 Sets the file name associated with the project. More...
 
void setLabelingEngineSettings (const QgsLabelingEngineSettings &settings)
 Sets project's global labeling engine settings. More...
 
void setMetadata (const QgsProjectMetadata &metadata)
 Sets the project's metadata store. More...
 
Q_DECL_DEPRECATED void setNonIdentifiableLayers (const QList< QgsMapLayer *> &layers)
 Set a list of layers which should not be taken into account on map identification. More...
 
Q_DECL_DEPRECATED void setNonIdentifiableLayers (const QStringList &layerIds)
 Set a list of layers which should not be taken into account on map identification. More...
 
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. More...
 
void setTitle (const QString &title)
 Sets the project's title. More...
 
void setTopologicalEditing (bool enabled)
 Convenience function to set topological editing. More...
 
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. More...
 
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. More...
 
QgsSnappingConfig snappingConfig () const
 The snapping configuration for this project. More...
 
QStringList subkeyList (const QString &scope, const QString &key) const
 Returns keys with keys – do not return keys that contain only values. More...
 
QgsMapLayertakeMapLayer (QgsMapLayer *layer)
 Takes a layer from the registry. More...
 
QString title () const
 Returns the project's title. More...
 
bool topologicalEditing () const
 Convenience function to query topological editing status. More...
 
QgsTransactionGrouptransactionGroup (const QString &providerKey, const QString &connString)
 Returns the matching transaction group from a provider key and connection string. More...
 
QMap< QPair< QString, QString >, QgsTransactionGroup * > transactionGroups ()
 Map of transaction groups. More...
 
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. More...
 
QString translate (const QString &context, const QString &sourceText, const char *disambiguation=nullptr, int n=-1) const override
 Translates the project with QTranslator and qm file. More...
 
bool trustLayerMetadata () const
 Returns true if the trust option is activated, false otherwise. More...
 
int validCount () const
 Returns the number of registered valid layers. More...
 
bool write (const QString &filename)
 Writes the project to a file. More...
 
bool write ()
 Writes the project to its current associated file (see fileName() ). More...
 
bool writeEntry (const QString &scope, const QString &key, bool value)
 Write a boolean entry to the project file. More...
 
bool writeEntry (const QString &scope, const QString &key, double value)
 Write a double entry to the project file. More...
 
bool writeEntry (const QString &scope, const QString &key, int value)
 Write an integer entry to the project file. More...
 
bool writeEntry (const QString &scope, const QString &key, const QString &value)
 Write a string entry to the project file. More...
 
bool writeEntry (const QString &scope, const QString &key, const QStringList &value)
 Write a string list entry to the project file. More...
 
QString writePath (const QString &filename) const
 Prepare a filename to save it to the project file. More...
 
- Public Member Functions inherited from QgsExpressionContextGenerator
virtual ~QgsExpressionContextGenerator ()=default
 
- Public Member Functions inherited from QgsProjectTranslator
virtual ~QgsProjectTranslator ()=default
 

Static Public Member Functions

static QgsProjectinstance ()
 Returns the QgsProject singleton instance. More...
 

Properties

QList< QgsVectorLayer * > avoidIntersectionsLayers
 
QgsCoordinateReferenceSystem crs
 
QString ellipsoid
 
QString fileName
 
QString homePath
 
QgsMapThemeCollection mapThemeCollection
 
QgsProjectMetadata metadata
 
QStringList nonIdentifiableLayers
 
QgsRelationManager relationManager
 
QgsSnappingConfig snappingConfig
 
QgsCoordinateTransformContext transformContext
 

Friends

class QgsConfigCache
 
class QgsProjectDirtyBlocker
 

Detailed Description

Reads and writes project states.

Note

Has two general kinds of state to make persistent. (I.e., to read and write.) First, QGIS proprietary information. Second plug-in information.

A singleton since there shall only be one active project at a time; and provides canonical location for plug-ins and main app to find/set properties.

Definition at line 89 of file qgsproject.h.

Constructor & Destructor Documentation

◆ QgsProject()

QgsProject::QgsProject ( QObject *  parent = nullptr)
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.

Definition at line 349 of file qgsproject.cpp.

◆ ~QgsProject()

QgsProject::~QgsProject ( )
override

Definition at line 406 of file qgsproject.cpp.

Member Function Documentation

◆ 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 606 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 595 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
mapLayerA layer to add to the registry
addToLegendIf 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.
takeOwnershipOwnership 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 2763 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
mapLayersA list of layer which should be added to the registry
addToLegendIf 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.
takeOwnershipOwnership 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()
Since
QGIS 1.8

Definition at line 2732 of file qgsproject.cpp.

◆ annotationManager() [1/2]

QgsAnnotationManager * QgsProject::annotationManager ( )

Returns pointer to the project's annotation manager.

Since
QGIS 3.0

Definition at line 2525 of file qgsproject.cpp.

◆ annotationManager() [2/2]

const QgsAnnotationManager * QgsProject::annotationManager ( ) const

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

Since
QGIS 3.0

Definition at line 2530 of file qgsproject.cpp.

◆ areaUnits()

QgsUnitTypes::AreaUnit QgsProject::areaUnits ( ) const

Convenience function to query default area measurement units for project.

See also
distanceUnits()
Since
QGIS 2.14

Definition at line 2453 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.

Since
QGIS 2.16

Definition at line 2584 of file qgsproject.cpp.

◆ auxiliaryStorage() [1/2]

const QgsAuxiliaryStorage * QgsProject::auxiliaryStorage ( ) const

Returns the current const auxiliary storage.

Since
QGIS 3.0

Definition at line 2889 of file qgsproject.cpp.

◆ auxiliaryStorage() [2/2]

QgsAuxiliaryStorage * QgsProject::auxiliaryStorage ( )

Returns the current auxiliary storage.

Since
QGIS 3.0

Definition at line 2894 of file qgsproject.cpp.

◆ avoidIntersectionsLayers()

QList<QgsVectorLayer *> QgsProject::avoidIntersectionsLayers ( ) const

A list of layers with which intersections should be avoided.

Since
QGIS 3.0

◆ avoidIntersectionsLayersChanged

void QgsProject::avoidIntersectionsLayersChanged ( )
signal

Emitted whenever avoidIntersectionsLayers has changed.

Since
QGIS 3.0

◆ 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 617 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()
Since
QGIS 2.4

Definition at line 675 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

◆ count()

int QgsProject::count ( ) const

Returns the number of registered layers.

Definition at line 2613 of file qgsproject.cpp.

◆ createEmbeddedGroup()

QgsLayerTreeGroup * QgsProject::createEmbeddedGroup ( const QString &  groupName,
const QString &  projectFilePath,
const QStringList &  invisibleLayers 
)

Create layer group instance defined in an arbitrary project file.

Since
QGIS 2.4

Definition at line 2314 of file qgsproject.cpp.

◆ createEmbeddedLayer()

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

Creates a maplayer instance defined in an arbitrary project file.

Caller takes ownership

Returns
the layer or 0 in case of error
Note
not available in Python bindings

Definition at line 2228 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.

Since
QGIS 3.0

Implements QgsExpressionContextGenerator.

Definition at line 1522 of file qgsproject.cpp.

◆ crs()

QgsCoordinateReferenceSystem QgsProject::crs ( ) const

Returns the project's native coordinate reference system.

See also
setCrs()
ellipsoid()
Since
QGIS 3.0

◆ crsChanged

void QgsProject::crsChanged ( )
signal

Emitted when the CRS of the project has changed.

Since
QGIS 3.0

◆ 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 1451 of file qgsproject.cpp.

◆ customVariablesChanged

void QgsProject::customVariablesChanged ( )
signal

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

Since
QGIS 3.0

◆ defaultCrsForNewLayers()

QgsCoordinateReferenceSystem QgsProject::defaultCrsForNewLayers ( ) const

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

Definition at line 2822 of file qgsproject.cpp.

◆ distanceUnits()

QgsUnitTypes::DistanceUnit QgsProject::distanceUnits ( ) const

Convenience function to query default distance measurement units for project.

See also
setDistanceUnits()
areaUnits()
Since
QGIS 2.14

Definition at line 2435 of file qgsproject.cpp.

◆ dumpProperties()

void QgsProject::dumpProperties ( ) const

Dump out current project properties to stderr.

Definition at line 2176 of file qgsproject.cpp.

◆ ellipsoid()

QString QgsProject::ellipsoid ( ) const

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

See also
setEllipsoid()
crs()
Since
QGIS 3.0

◆ ellipsoidChanged

void QgsProject::ellipsoidChanged ( const QString &  ellipsoid)
signal

Emitted when the project ellipsoid is changed.

See also
setEllipsoid()
ellipsoid()
Since
QGIS 3.0

◆ entryList()

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

Returns keys with values – do not return keys that contain other keys.

Note
equivalent to QgsSettings entryList()

Definition at line 2142 of file qgsproject.cpp.

◆ error()

QString QgsProject::error ( ) const

Returns error message from previous read/write.

Definition at line 2202 of file qgsproject.cpp.

◆ evaluateDefaultValues()

bool QgsProject::evaluateDefaultValues ( ) const

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

Since
QGIS 2.16

Definition at line 2400 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()
Since
QGIS 2.9
Deprecated:
Use absoluteFilePath(), baseName() or lastModifiedTime() instead

Definition at line 571 of file qgsproject.cpp.

◆ fileName()

QString QgsProject::fileName ( ) const

Returns the project's file name.

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

See also
setFileName()
fileInfo()

◆ fileNameChanged

void QgsProject::fileNameChanged ( )
signal

Emitted when the file name of the project changes.

◆ 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 2945 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()

◆ 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 425 of file qgsproject.cpp.

◆ isDirty()

bool QgsProject::isDirty ( ) const

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

Definition at line 450 of file qgsproject.cpp.

◆ isDirtyChanged

void QgsProject::isDirtyChanged ( bool  dirty)
signal

Emitted when the project dirty status changes.

Parameters
dirtyTrue 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 2727 of file qgsproject.cpp.

◆ labelingEngineSettings()

const QgsLabelingEngineSettings & QgsProject::labelingEngineSettings ( ) const

Returns project's global labeling engine settings.

Since
QGIS 3.0

Definition at line 1486 of file qgsproject.cpp.

◆ labelingEngineSettingsChanged

void QgsProject::labelingEngineSettingsChanged ( )
signal

Emitted when global configuration of the labeling engine changes.

Since
QGIS 3.0

◆ 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 581 of file qgsproject.cpp.

◆ layerIsEmbedded()

QString QgsProject::layerIsEmbedded ( const QString &  id) const

Returns project file path if layer is embedded from other project file. Returns empty string if layer is not embedded.

Definition at line 2218 of file qgsproject.cpp.

◆ layerLoaded

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

Emitted when a layer from a projects was read.

Parameters
icurrent layer
nnumber of layers

◆ layerRemoved

void QgsProject::layerRemoved ( const QString &  layerId)
signal

Emitted after a layer was removed from the registry.

Parameters
layerIdThe 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()
Since
QGIS 2.16

Definition at line 743 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
layersList 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
layerIdsA 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.

/since QGIS 3.0

Definition at line 1491 of file qgsproject.cpp.

◆ layerStore() [2/2]

const QgsMapLayerStore * QgsProject::layerStore ( ) const

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

/since QGIS 3.0

Definition at line 1496 of file qgsproject.cpp.

◆ layersWillBeRemoved [1/2]

void QgsProject::layersWillBeRemoved ( const QStringList &  layerIds)
signal

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

Parameters
layerIdsA list of IDs for the layers which are to be removed.
See also
layerWillBeRemoved()
layersRemoved()

◆ layersWillBeRemoved [2/2]

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

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

Parameters
layersA list of 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.

Since
QGIS 2.4

Definition at line 534 of file qgsproject.h.

◆ layerTreeRoot()

QgsLayerTree * QgsProject::layerTreeRoot ( ) const

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

Since
QGIS 2.4

Definition at line 2515 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
layerIdThe 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
layerThe layer to be removed.
Note
Consider using layersWillBeRemoved() instead
See also
layersWillBeRemoved()
layerRemoved()

◆ layoutManager() [1/2]

const QgsLayoutManager * QgsProject::layoutManager ( ) const

Returns the project's layout manager, which manages compositions within the project.

Note
not available in Python bindings
Since
QGIS 3.0

Definition at line 2505 of file qgsproject.cpp.

◆ layoutManager() [2/2]

QgsLayoutManager * QgsProject::layoutManager ( )

Returns the project's layout manager, which manages compositions within the project.

Since
QGIS 3.0

Definition at line 2510 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
layersList of QgsMapLayer which were added to the legend.

◆ 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
layerNamethe layer name
messagesa list of pairs of Qgis::MessageLevel and messages
Since
3.2

◆ mapLayer()

QgsMapLayer * QgsProject::mapLayer ( const QString &  layerId) const

Retrieve a pointer to a registered layer by layer ID.

Parameters
layerIdID of layer to retrieve
Returns
matching layer, or nullptr if no matching layer found
See also
mapLayersByName()
mapLayers()

Definition at line 2623 of file qgsproject.cpp.

◆ mapLayers()

QMap< QString, QgsMapLayer * > QgsProject::mapLayers ( const bool  validOnly = false) const

Returns a map of all registered layers by layer ID.

Parameters
validOnlyif set only valid layers will be returned
See also
mapLayer()
mapLayersByName()
layers()

Definition at line 2812 of file qgsproject.cpp.

◆ mapLayersByName()

QList< QgsMapLayer * > QgsProject::mapLayersByName ( const QString &  layerName) const

Retrieve a list of matching registered layers by layer name.

Parameters
layerNamename of layers to match
Returns
list of matching layers
See also
mapLayer()
mapLayers()

Definition at line 2628 of file qgsproject.cpp.

◆ mapThemeCollection()

QgsMapThemeCollection* QgsProject::mapThemeCollection ( )

Returns pointer to the project's map theme collection.

Note
renamed in QGIS 3.0, formerly QgsVisibilityPresetCollection
Since
QGIS 2.12

◆ 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.

Since
QGIS 3.0

◆ metadata()

const QgsProjectMetadata& QgsProject::metadata ( ) const

Returns a reference to the project's metadata store.

See also
setMetadata()
metadataChanged()
Since
QGIS 3.2

◆ 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.

Since
QGIS 3.0

◆ nonIdentifiableLayers()

Q_DECL_DEPRECATED QStringList QgsProject::nonIdentifiableLayers ( ) const

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

Deprecated:
since QGIS 3.4 use QgsMapLayer::setFlags() instead

◆ nonIdentifiableLayersChanged

Q_DECL_DEPRECATED void QgsProject::nonIdentifiableLayersChanged ( QStringList  nonIdentifiableLayers)
signal

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

Deprecated:
since QGIS 3.4

◆ oldProjectVersionWarning

void QgsProject::oldProjectVersionWarning ( const QString &  )
signal

Emitted when an old project file is read.

◆ 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.

Since
QGIS 3.0

Definition at line 2181 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 2495 of file qgsproject.cpp.

◆ 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 null pointer. The project storage object is inferred from fileName() of the project.

Since
QGIS 3.2

Definition at line 576 of file qgsproject.cpp.

◆ read() [1/2]

bool QgsProject::read ( const QString &  filename)

Reads given project file from the given file.

Parameters
filenamename of project file to read
Returns
true if project file has been read successfully

Definition at line 991 of file qgsproject.cpp.

◆ read() [2/2]

bool QgsProject::read ( )

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

Returns
true if project file has been read successfully

Definition at line 998 of file qgsproject.cpp.

◆ readBoolEntry()

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

Definition at line 2109 of file qgsproject.cpp.

◆ readDoubleEntry()

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

Definition at line 2089 of file qgsproject.cpp.

◆ readEntry()

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

Definition at line 2038 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
layerNoderepresents a QgsProject DOM node that encodes a specific layer.

Definition at line 1614 of file qgsproject.cpp.

◆ readListEntry()

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

Key value accessors.

keys would be the familiar QgsSettings-like '/' delimited entries, implying a hierarchy of keys and corresponding values

Definition at line 2011 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
mapLayerThe map layer which is being initialized
layerNodeThe layer node from the project file

◆ readNumEntry()

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

Definition at line 2062 of file qgsproject.cpp.

◆ readPath()

QString QgsProject::readPath ( const QString &  filename) const

Turn filename read from the project file to an absolute path.

Definition at line 2187 of file qgsproject.cpp.

◆ readProject

void QgsProject::readProject ( const QDomDocument &  )
signal

Emitted when a project is being read.

◆ readProjectWithContext

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

Emitted when a project is being read.

And passing the /a context

◆ 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
translationContextwhere the objects will be registered
parentparent-container containing list of children
layerIdto store under the correct context
Since
QGIS 3.4

Definition at line 478 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 496 of file qgsproject.cpp.

◆ relationManager()

QgsRelationManager* QgsProject::relationManager ( ) const

◆ 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 2802 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 2797 of file qgsproject.cpp.

◆ removeEntry()

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

Remove the given key.

Definition at line 2130 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
layerIdID of the layer to remove
Note
As a side-effect the QgsProject instance is marked dirty.
See also
removeMapLayers()
removeAllMapLayers()

Definition at line 2782 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
layerThe layer to remove. Null pointers are ignored.
Note
As a side-effect the QgsProject instance is marked dirty.
See also
removeMapLayers()
removeAllMapLayers()

Definition at line 2787 of file qgsproject.cpp.

◆ removeMapLayers() [1/2]

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
layerIdslist of IDs of the layers to remove
Note
As a side-effect the QgsProject instance is marked dirty.
See also
removeMapLayer()
removeAllMapLayers()
Since
QGIS 1.8

Definition at line 2772 of file qgsproject.cpp.

◆ removeMapLayers() [2/2]

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
layersA list of layers to remove. Null pointers are ignored.
Note
As a side-effect the QgsProject instance is marked dirty.
See also
removeMapLayer()
removeAllMapLayers()

Definition at line 2777 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:
since QGIS 3.4 use QgsMapLayer::flags() instead
Since
QGIS 3.2

Definition at line 2915 of file qgsproject.cpp.

◆ setAreaUnits()

void QgsProject::setAreaUnits ( QgsUnitTypes::AreaUnit  unit)

Sets the default area measurement units for the project.

See also
areaUnits()
setDistanceUnits()
Since
QGIS 3.0

Definition at line 2466 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.

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

Since
QGIS 2.16

Definition at line 2589 of file qgsproject.cpp.

◆ setAvoidIntersectionsLayers()

void QgsProject::setAvoidIntersectionsLayers ( const QList< QgsVectorLayer *> &  layers)

A list of layers with which intersections should be avoided.

Since
QGIS 3.0

Definition at line 1513 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 2212 of file qgsproject.cpp.

◆ setCrs()

void QgsProject::setCrs ( const QgsCoordinateReferenceSystem crs)

Sets the project's native coordinate reference system.

See also
crs()
setEllipsoid()
Since
QGIS 3.0

Definition at line 636 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 1456 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
Since
QGIS 2.4

Definition at line 455 of file qgsproject.cpp.

◆ setDistanceUnits()

void QgsProject::setDistanceUnits ( QgsUnitTypes::DistanceUnit  unit)

Sets the default distance measurement units for the project.

See also
distanceUnits()
setAreaUnits()
Since
QGIS 3.0

Definition at line 2448 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()
Since
QGIS 3.0

Definition at line 655 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.

Since
QGIS 2.16

Definition at line 2405 of file qgsproject.cpp.

◆ setFileName()

void QgsProject::setFileName ( const QString &  name)

Sets the file name associated with the project.

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

Parameters
nameproject file name
See also
fileName()

Definition at line 549 of file qgsproject.cpp.

◆ setLabelingEngineSettings()

void QgsProject::setLabelingEngineSettings ( const QgsLabelingEngineSettings settings)

Sets project's global labeling engine settings.

Since
QGIS 3.0

Definition at line 1480 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 2904 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:
since QGIS 3.4 use QgsMapLayer::setFlags() instead

Definition at line 2535 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:
since QGIS 3.4 use QgsMapLayer::setFlags() instead

Definition at line 2554 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 467 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:
since QGIS 3.4 use QgsMapLayer::setFlags() instead
Since
QGIS 3.2

Definition at line 2930 of file qgsproject.cpp.

◆ setSnappingConfig

void QgsProject::setSnappingConfig ( const QgsSnappingConfig snappingConfig)
slot

The snapping configuration for this project.

Since
QGIS 3.0

Definition at line 857 of file qgsproject.cpp.

◆ setTitle()

void QgsProject::setTitle ( const QString &  title)

Sets the project's title.

Parameters
titlenew title
Note
Since QGIS 3.2 this is just a shortcut to setting the title in the project's metadata().
See also
title()
Since
QGIS 2.4

Definition at line 434 of file qgsproject.cpp.

◆ setTopologicalEditing()

void QgsProject::setTopologicalEditing ( bool  enabled)

Convenience function to set topological editing.

Definition at line 2424 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()
Since
QGIS 3.0

Definition at line 666 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
trustTrue to trust the project, false otherwise
Since
QGIS 3.0

Definition at line 2843 of file qgsproject.cpp.

◆ snappingConfig()

QgsSnappingConfig QgsProject::snappingConfig ( ) const

The snapping configuration for this project.

Since
QGIS 3.0

◆ snappingConfigChanged

void QgsProject::snappingConfigChanged ( const QgsSnappingConfig config)
signal

Emitted whenever the configuration for snapping has changed.

◆ subkeyList()

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

Returns keys with keys – do not return keys that contain only values.

Note
equivalent to QgsSettings subkeyList()

Definition at line 2159 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()
Since
QGIS 3.0

Definition at line 2792 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 445 of file qgsproject.cpp.

◆ topologicalEditing()

bool QgsProject::topologicalEditing ( ) const

Convenience function to query topological editing status.

Definition at line 2430 of file qgsproject.cpp.

◆ topologicalEditingChanged

void QgsProject::topologicalEditingChanged ( )
signal

Emitted when the topological editing flag has changed.

Since
QGIS 3.0

◆ 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 2817 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
Since
QGIS 2.16

Definition at line 2602 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.

Since
QGIS 3.0

◆ 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()
Since
QGIS 3.0

◆ transformContextChanged

void QgsProject::transformContextChanged ( )
signal

Emitted when the project transformContext() is changed.

See also
transformContext()
Since
QGIS 3.0

◆ translate()

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

Translates the project with QTranslator and qm file.

Returns
the result string (in case there is no QTranslator loaded the sourceText)
Parameters
contextdescribing layer etc.
sourceTextis the identifier of this text
disambiguationit's the disambiguation
nif -1 uses the appropriate form
Since
QGIS 3.4

Implements QgsProjectTranslator.

Definition at line 2956 of file qgsproject.cpp.

◆ trustLayerMetadata()

bool QgsProject::trustLayerMetadata ( ) const
inline

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.

Since
QGIS 3.0

Definition at line 928 of file qgsproject.h.

◆ validCount()

int QgsProject::validCount ( ) const

Returns the number of registered valid layers.

Definition at line 2618 of file qgsproject.cpp.

◆ write() [1/2]

bool QgsProject::write ( const QString &  filename)

Writes the project to a file.

Parameters
filenamedestination 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
Since
QGIS 3.0

Definition at line 1636 of file qgsproject.cpp.

◆ write() [2/2]

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 1643 of file qgsproject.cpp.

◆ writeEntry() [1/5]

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

Write a boolean entry 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

Definition at line 1956 of file qgsproject.cpp.

◆ writeEntry() [2/5]

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

Write a double entry 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

Definition at line 1967 of file qgsproject.cpp.

◆ writeEntry() [3/5]

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

Write an integer entry 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.

Definition at line 1978 of file qgsproject.cpp.

◆ writeEntry() [4/5]

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

Write a string entry 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.

Definition at line 1989 of file qgsproject.cpp.

◆ writeEntry() [5/5]

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

Write a string list entry 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.

Definition at line 2000 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
mapLayerThe map layer which is being initialized
layerElemThe layer element from the project file
docThe 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 2192 of file qgsproject.cpp.

◆ writeProject

void QgsProject::writeProject ( QDomDocument &  )
signal

Emitted when the project is being written.

Friends And Related Function Documentation

◆ QgsConfigCache

friend class QgsConfigCache
friend

Definition at line 1467 of file qgsproject.h.

◆ QgsProjectDirtyBlocker

friend class QgsProjectDirtyBlocker
friend

Definition at line 1464 of file qgsproject.h.

Property Documentation

◆ avoidIntersectionsLayers

QList< QgsVectorLayer * > QgsProject::avoidIntersectionsLayers
readwrite

Definition at line 101 of file qgsproject.h.

◆ crs

QgsCoordinateReferenceSystem QgsProject::crs
readwrite

Definition at line 95 of file qgsproject.h.

◆ ellipsoid

QString QgsProject::ellipsoid
readwrite

Definition at line 97 of file qgsproject.h.

◆ fileName

QString QgsProject::fileName
readwrite

Definition at line 93 of file qgsproject.h.

◆ homePath

QString QgsProject::homePath
readwrite

Definition at line 94 of file qgsproject.h.

◆ mapThemeCollection

QgsMapThemeCollection * QgsProject::mapThemeCollection
read

Definition at line 98 of file qgsproject.h.

◆ metadata

const QgsProjectMetadata & QgsProject::metadata
readwrite

Definition at line 102 of file qgsproject.h.

◆ nonIdentifiableLayers

QStringList QgsProject::nonIdentifiableLayers
readwrite

Definition at line 92 of file qgsproject.h.

◆ relationManager

QgsRelationManager * QgsProject::relationManager
read

Definition at line 100 of file qgsproject.h.

◆ snappingConfig

QgsSnappingConfig QgsProject::snappingConfig
readwrite

Definition at line 99 of file qgsproject.h.

◆ transformContext

QgsCoordinateTransformContext QgsProject::transformContext
readwrite

Definition at line 96 of file qgsproject.h.


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