QGIS API Documentation  3.20.0-Odense (decaadbb31)
Public Types | Public Slots | Signals | Public Member Functions | Static Public Member Functions | Protected Member Functions | Protected Attributes | Properties | Friends | List of all members
QgsMapLayer Class Referenceabstract

Base class for all map layer types. More...

#include <qgsmaplayer.h>

Inheritance diagram for QgsMapLayer:
Inheritance graph
[legend]

Public Types

enum  LayerFlag { Identifiable = 1 << 0 , Removable = 1 << 1 , Searchable = 1 << 2 , Private = 1 << 3 }
 Flags for the map layer. More...
 
enum  PropertyType { Style = 0 , Metadata }
 Maplayer has a style and a metadata property. More...
 
enum  ReadFlag { FlagDontResolveLayers = 1 << 0 , FlagTrustLayerMetadata = 1 << 1 , FlagReadExtentFromXml = 1 << 2 }
 Flags which control project read behavior. More...
 
enum  StyleCategory {
  LayerConfiguration = 1 << 0 , Symbology = 1 << 1 , Symbology3D = 1 << 2 , Labeling = 1 << 3 ,
  Fields = 1 << 4 , Forms = 1 << 5 , Actions = 1 << 6 , MapTips = 1 << 7 ,
  Diagrams = 1 << 8 , AttributeTable = 1 << 9 , Rendering = 1 << 10 , CustomProperties = 1 << 11 ,
  GeometryOptions = 1 << 12 , Relations = 1 << 13 , Temporal = 1 << 14 , Legend = 1 << 15 ,
  Elevation = 1 << 16 , Notes = 1 << 17 , AllStyleCategories
}
 Categories of style to distinguish appropriate sections for import/export. More...
 

Public Slots

void emitStyleChanged ()
 Triggers an emission of the styleChanged() signal. More...
 
QgsProjectproject () const
 Returns the parent project if this map layer is added to a project. More...
 
virtual bool setDependencies (const QSet< QgsMapLayerDependency > &layers)
 Sets the list of dependencies. More...
 
void setMaximumScale (double scale)
 Sets the maximum map scale (i.e. More...
 
void setMinimumScale (double scale)
 Sets the minimum map scale (i.e. More...
 
void setRefreshOnNofifyMessage (const QString &message)
 Set the notification message that triggers repaint If refresh on notification is enabled, the notification will triggerRepaint only if the notification message is equal to. More...
 
void setRefreshOnNotifyEnabled (bool enabled)
 Set whether provider notification is connected to triggerRepaint. More...
 
void setScaleBasedVisibility (bool enabled)
 Sets whether scale based visibility is enabled for the layer. More...
 
virtual void setTransformContext (const QgsCoordinateTransformContext &transformContext)=0
 Sets the coordinate transform context to transformContext. More...
 
void trigger3DUpdate ()
 Will advise any 3D maps that this layer requires to be updated in the scene. More...
 
void triggerRepaint (bool deferredUpdate=false)
 Will advise the map canvas (and any other interested party) that this layer requires to be repainted. More...
 

Signals

void autoRefreshIntervalChanged (int interval)
 Emitted when the auto refresh interval changes. More...
 
void beforeResolveReferences (QgsProject *project)
 Emitted when all layers are loaded and references can be resolved, just before the references of this layer are resolved. More...
 
void blendModeChanged (QPainter::CompositionMode blendMode)
 Signal emitted when the blend mode is changed, through QgsMapLayer::setBlendMode() More...
 
void configChanged ()
 Emitted whenever the configuration is changed. More...
 
void crsChanged ()
 Emit a signal that layer's CRS has been reset. More...
 
void customPropertyChanged (const QString &key)
 Emitted when a custom property of the layer has been changed or removed. More...
 
void dataChanged ()
 Data of layer changed. More...
 
void dataSourceChanged ()
 Emitted whenever the layer's data source has been changed. More...
 
void dependenciesChanged ()
 Emitted when dependencies are changed. More...
 
void flagsChanged ()
 Emitted when layer's flags have been modified. More...
 
void isValidChanged ()
 Emitted when the validity of this layer changed. More...
 
void legendChanged ()
 Signal emitted when legend of the layer has changed. More...
 
void metadataChanged ()
 Emitted when the layer's metadata is changed. More...
 
void nameChanged ()
 Emitted when the name has been changed. More...
 
void opacityChanged (double opacity)
 Emitted when the layer's opacity is changed, where opacity is a value between 0 (transparent) and 1 (opaque). More...
 
void recalculateExtents () const
 This is used to send a request that any mapcanvas using this layer update its extents. More...
 
void renderer3DChanged ()
 Signal emitted when 3D renderer associated with the layer has changed. More...
 
void rendererChanged ()
 Signal emitted when renderer is changed. More...
 
void repaintRequested (bool deferredUpdate=false)
 By emitting this signal the layer tells that either appearance or content have been changed and any view showing the rendered layer should refresh itself. More...
 
void request3DUpdate ()
 Signal emitted when a layer requires an update in any 3D maps. More...
 
void statusChanged (const QString &status)
 Emit a signal with status (e.g. to be caught by QgisApp and display a msg on status bar) More...
 
void styleChanged ()
 Signal emitted whenever a change affects the layer's style. More...
 
void styleLoaded (QgsMapLayer::StyleCategories categories)
 Emitted when a style has been loaded. More...
 
void willBeDeleted ()
 Emitted in the destructor when the layer is about to be deleted, but it is still in a perfectly valid state: the last chance for other pieces of code for some cleanup if they use the layer. More...
 

Public Member Functions

 QgsMapLayer (QgsMapLayer const &)=delete
 QgsMapLayer cannot be copied. More...
 
 QgsMapLayer (QgsMapLayerType type=QgsMapLayerType::VectorLayer, const QString &name=QString(), const QString &source=QString())
 Constructor for QgsMapLayer. More...
 
 ~QgsMapLayer () override
 
QString abstract () const
 Returns the abstract of the layer used by QGIS Server in GetCapabilities request. More...
 
virtual bool accept (QgsStyleEntityVisitorInterface *visitor) const
 Accepts the specified symbology visitor, causing it to visit all symbols associated with the layer. More...
 
QString attribution () const
 Returns the attribution of the layer used by QGIS Server in GetCapabilities request. More...
 
QString attributionUrl () const
 Returns the attribution URL of the layer used by QGIS Server in GetCapabilities request. More...
 
int autoRefreshInterval () const
 Returns the auto refresh interval (in milliseconds). More...
 
QPainter::CompositionMode blendMode () const
 Returns the current blending mode for a layer. More...
 
virtual QgsMapLayerclone () const =0
 Returns a new instance equivalent to this one except for the id which is still unique. More...
 
virtual QgsMapLayerRenderercreateMapRenderer (QgsRenderContext &rendererContext)=0
 Returns new instance of QgsMapLayerRenderer that will be used for rendering of given context. More...
 
QgsCoordinateReferenceSystem crs () const
 Returns the layer's spatial reference system. More...
 
const QgsObjectCustomPropertiescustomProperties () const
 Read all custom properties from layer. More...
 
Q_INVOKABLE QVariant customProperty (const QString &value, const QVariant &defaultValue=QVariant()) const
 Read a custom property from layer. More...
 
Q_INVOKABLE QStringList customPropertyKeys () const
 Returns list of all keys within custom properties. More...
 
virtual Q_INVOKABLE QgsDataProviderdataProvider ()
 Returns the layer's data provider, it may be nullptr. More...
 
virtual const QgsDataProviderdataProvider () const
 Returns the layer's data provider in a const-correct manner, it may be nullptr. More...
 
QString dataUrl () const
 Returns the DataUrl of the layer used by QGIS Server in GetCapabilities request. More...
 
QString dataUrlFormat () const
 Returns the DataUrl format of the layer used by QGIS Server in GetCapabilities request. More...
 
virtual QSet< QgsMapLayerDependencydependencies () const
 Gets the list of dependencies. More...
 
virtual QgsMapLayerElevationPropertieselevationProperties ()
 Returns the layer's elevation properties. More...
 
virtual QgsError error () const
 Gets current status error. More...
 
void exportNamedMetadata (QDomDocument &doc, QString &errorMsg) const
 Export the current metadata of this layer as named metadata in a QDomDocument. More...
 
virtual void exportNamedStyle (QDomDocument &doc, QString &errorMsg, const QgsReadWriteContext &context=QgsReadWriteContext(), QgsMapLayer::StyleCategories categories=QgsMapLayer::AllStyleCategories) const
 Export the properties of this layer as named style in a QDomDocument. More...
 
virtual void exportSldStyle (QDomDocument &doc, QString &errorMsg) const
 Export the properties of this layer as SLD style in a QDomDocument. More...
 
virtual QgsRectangle extent () const
 Returns the extent of the layer. More...
 
QgsMapLayer::LayerFlags flags () const
 Returns the flags for this layer. More...
 
bool hasAutoRefreshEnabled () const
 Returns true if auto refresh is enabled for the layer. More...
 
bool hasScaleBasedVisibility () const
 Returns whether scale based visibility is enabled for the layer. More...
 
virtual QString htmlMetadata () const
 Obtain a formatted HTML string containing assorted metadata for this layer. More...
 
QString id () const
 Returns the layer's unique ID, which is used to access this layer from QgsProject. More...
 
bool importNamedMetadata (QDomDocument &document, QString &errorMessage)
 Import the metadata of this layer from a QDomDocument. More...
 
virtual bool importNamedStyle (QDomDocument &doc, QString &errorMsg, QgsMapLayer::StyleCategories categories=QgsMapLayer::AllStyleCategories)
 Import the properties of this layer from a QDomDocument. More...
 
virtual bool isEditable () const
 Returns true if the layer can be edited. More...
 
bool isInScaleRange (double scale) const
 Tests whether the layer should be visible at the specified scale. More...
 
bool isRefreshOnNotifyEnabled () const
 Returns true if the refresh on provider nofification is enabled. More...
 
virtual bool isSpatial () const
 Returns true if the layer is considered a spatial layer, ie it has some form of geometry associated with it. More...
 
virtual bool isTemporary () const
 Returns true if the layer is considered a temporary layer. More...
 
bool isValid () const
 Returns the status of the layer. More...
 
QString keywordList () const
 Returns the keyword list of the layer used by QGIS Server in GetCapabilities request. More...
 
QgsMapLayerLegendlegend () const
 Can be nullptr. More...
 
QString legendUrl () const
 Returns the URL for the layer's legend. More...
 
QString legendUrlFormat () const
 Returns the format for a URL based layer legend. More...
 
virtual QString loadDefaultMetadata (bool &resultFlag)
 Retrieve the default metadata for this layer if one exists (either as a .qmd file on disk or as a record in the users metadata table in their personal qgis.db) More...
 
virtual QString loadDefaultStyle (bool &resultFlag)
 Retrieve the default style for this layer if one exists (either as a .qml file on disk or as a record in the users style table in their personal qgis.db) More...
 
virtual QString loadNamedMetadata (const QString &uri, bool &resultFlag)
 Retrieve a named metadata for this layer if one exists (either as a .qmd file on disk or as a record in the users style table in their personal qgis.db) More...
 
bool loadNamedMetadataFromDatabase (const QString &db, const QString &uri, QString &qmd)
 Retrieve a named metadata for this layer from a sqlite database. More...
 
virtual QString loadNamedStyle (const QString &uri, bool &resultFlag, QgsMapLayer::StyleCategories categories=QgsMapLayer::AllStyleCategories)
 Retrieve a named style for this layer if one exists (either as a .qml file on disk or as a record in the users style table in their personal qgis.db) More...
 
virtual bool loadNamedStyleFromDatabase (const QString &db, const QString &uri, QString &qml)
 Retrieve a named style for this layer from a sqlite database. More...
 
virtual QString loadSldStyle (const QString &uri, bool &resultFlag)
 Attempts to style the layer using the formatting from an SLD type file. More...
 
double maximumScale () const
 Returns the maximum map scale (i.e. More...
 
virtual const QgsLayerMetadatametadata () const
 Returns a reference to the layer's metadata store. More...
 
virtual QString metadataUri () const
 Retrieve the metadata URI for this layer (either as a .qmd file on disk or as a record in the users style table in their personal qgis.db) More...
 
QString metadataUrl () const
 Returns the metadata URL of the layer used by QGIS Server in GetCapabilities request. More...
 
QString metadataUrlFormat () const
 Returns the metadata format of the layer used by QGIS Server in GetCapabilities request. More...
 
QString metadataUrlType () const
 Returns the metadata type of the layer used by QGIS Server in GetCapabilities request. More...
 
double minimumScale () const
 Returns the minimum map scale (i.e. More...
 
QString name () const
 Returns the display name of the layer. More...
 
virtual double opacity () const
 Returns the opacity for the layer, where opacity is a value between 0 (totally transparent) and 1.0 (fully opaque). More...
 
QgsMapLayeroperator= (QgsMapLayer const &)=delete
 QgsMapLayer cannot be copied. More...
 
QString originalXmlProperties () const
 Returns the XML properties of the original layer as they were when the layer was first read from the project file. More...
 
QString providerType () const
 Returns the provider type (provider key) for this layer. More...
 
QString publicSource () const
 Gets a version of the internal layer definition that has sensitive bits removed (for example, the password). More...
 
bool readLayerXml (const QDomElement &layerElement, QgsReadWriteContext &context, QgsMapLayer::ReadFlags flags=QgsMapLayer::ReadFlags())
 Sets state from DOM document. More...
 
bool readOnly () const
 Returns if this layer is read only. More...
 
virtual bool readSld (const QDomNode &node, QString &errorMessage)
 
virtual bool readStyle (const QDomNode &node, QString &errorMessage, QgsReadWriteContext &context, StyleCategories categories=AllStyleCategories)
 Read the style for the current layer from the DOM node supplied. More...
 
virtual bool readSymbology (const QDomNode &node, QString &errorMessage, QgsReadWriteContext &context, StyleCategories categories=AllStyleCategories)=0
 Read the symbology for the current layer from the DOM node supplied. More...
 
QString refreshOnNotifyMessage () const
 Returns the message that should be notified by the provider to triggerRepaint. More...
 
virtual Q_INVOKABLE void reload ()
 Synchronises with changes in the datasource. More...
 
void removeCustomProperty (const QString &key)
 Remove a custom property from layer. More...
 
QgsAbstract3DRendererrenderer3D () const
 Returns 3D renderer associated with the layer. More...
 
virtual void resolveReferences (QgsProject *project)
 Resolve references to other layers (kept as layer IDs after reading XML) into layer objects. More...
 
virtual QString saveDefaultMetadata (bool &resultFlag)
 Save the current metadata of this layer as the default metadata (either as a .qmd file on disk or as a record in the users style table in their personal qgis.db) More...
 
virtual QString saveDefaultStyle (bool &resultFlag)
 Save the properties of this layer as the default style (either as a .qml file on disk or as a record in the users style table in their personal qgis.db) More...
 
QString saveNamedMetadata (const QString &uri, bool &resultFlag)
 Save the current metadata of this layer as a named metadata (either as a .qmd file on disk or as a record in the users style table in their personal qgis.db) More...
 
virtual QString saveNamedStyle (const QString &uri, bool &resultFlag, StyleCategories categories=AllStyleCategories)
 Save the properties of this layer as a named style (either as a .qml file on disk or as a record in the users style table in their personal qgis.db) More...
 
virtual QString saveSldStyle (const QString &uri, bool &resultFlag) const
 Saves the properties of this layer to an SLD format file. More...
 
void setAbstract (const QString &abstract)
 Sets the abstract of the layer used by QGIS Server in GetCapabilities request. More...
 
void setAttribution (const QString &attrib)
 Sets the attribution of the layer used by QGIS Server in GetCapabilities request. More...
 
void setAttributionUrl (const QString &attribUrl)
 Sets the attribution URL of the layer used by QGIS Server in GetCapabilities request. More...
 
void setAutoRefreshEnabled (bool enabled)
 Sets whether auto refresh is enabled for the layer. More...
 
void setAutoRefreshInterval (int interval)
 Sets the auto refresh interval (in milliseconds) for the layer. More...
 
void setBlendMode (QPainter::CompositionMode blendMode)
 Set the blending mode used for rendering a layer. More...
 
void setCrs (const QgsCoordinateReferenceSystem &srs, bool emitSignal=true)
 Sets layer's spatial reference system. More...
 
void setCustomProperties (const QgsObjectCustomProperties &properties)
 Set custom properties for layer. More...
 
Q_INVOKABLE void setCustomProperty (const QString &key, const QVariant &value)
 Set a custom property for layer. More...
 
void setDataSource (const QString &dataSource, const QString &baseName, const QString &provider, bool loadDefaultStyleFlag=false)
 Updates the data source of the layer. More...
 
void setDataSource (const QString &dataSource, const QString &baseName, const QString &provider, const QgsDataProvider::ProviderOptions &options, bool loadDefaultStyleFlag=false)
 Updates the data source of the layer. More...
 
void setDataSource (const QString &dataSource, const QString &baseName, const QString &provider, const QgsDataProvider::ProviderOptions &options, QgsDataProvider::ReadFlags flags)
 Updates the data source of the layer. More...
 
void setDataUrl (const QString &dataUrl)
 Sets the DataUrl of the layer used by QGIS Server in GetCapabilities request. More...
 
void setDataUrlFormat (const QString &dataUrlFormat)
 Sets the DataUrl format of the layer used by QGIS Server in GetCapabilities request. More...
 
void setFlags (QgsMapLayer::LayerFlags flags)
 Returns the flags for this layer. More...
 
void setKeywordList (const QString &keywords)
 Sets the keyword list of the layer used by QGIS Server in GetCapabilities request. More...
 
virtual void setLayerOrder (const QStringList &layers)
 Reorders the previously selected sublayers of this layer from bottom to top. More...
 
void setLegend (QgsMapLayerLegend *legend)
 Assign a legend controller to the map layer. More...
 
void setLegendUrl (const QString &legendUrl)
 Sets the URL for the layer's legend. More...
 
void setLegendUrlFormat (const QString &legendUrlFormat)
 Sets the format for a URL based layer legend. More...
 
virtual void setMetadata (const QgsLayerMetadata &metadata)
 Sets the layer's metadata store. More...
 
void setMetadataUrl (const QString &metaUrl)
 Sets the metadata URL of the layer used by QGIS Server in GetCapabilities request. More...
 
void setMetadataUrlFormat (const QString &metaUrlFormat)
 Sets the metadata format of the layer used by QGIS Server in GetCapabilities request. More...
 
void setMetadataUrlType (const QString &metaUrlType)
 Set the metadata type of the layer used by QGIS Server in GetCapabilities request MetadataUrlType indicates the standard to which the metadata complies. More...
 
void setName (const QString &name)
 Set the display name of the layer. More...
 
virtual void setOpacity (double opacity)
 Sets the opacity for the layer, where opacity is a value between 0 (totally transparent) and 1.0 (fully opaque). More...
 
void setOriginalXmlProperties (const QString &originalXmlProperties)
 Sets the original XML properties for the layer to originalXmlProperties. More...
 
void setRenderer3D (QgsAbstract3DRenderer *renderer)
 Sets 3D renderer for the layer. More...
 
void setShortName (const QString &shortName)
 Sets the short name of the layer used by QGIS Server to identify the layer. More...
 
virtual void setSubLayerVisibility (const QString &name, bool visible)
 Set the visibility of the given sublayer name. More...
 
void setTitle (const QString &title)
 Sets the title of the layer used by QGIS Server in GetCapabilities request. More...
 
QString shortName () const
 Returns the short name of the layer used by QGIS Server to identify the layer. More...
 
QString source () const
 Returns the source for the layer. More...
 
QgsMapLayerStyleManagerstyleManager () const
 Gets access to the layer's style manager. More...
 
virtual QString styleURI () const
 Retrieve the style URI for this layer (either as a .qml file on disk or as a record in the users style table in their personal qgis.db) More...
 
virtual QStringList subLayers () const
 Returns the sublayers of this layer. More...
 
virtual QgsMapLayerTemporalPropertiestemporalProperties ()
 Returns the layer's temporal properties. More...
 
virtual QDateTime timestamp () const
 Time stamp of data source in the moment when data/metadata were loaded by provider. More...
 
QString title () const
 Returns the title of the layer used by QGIS Server in GetCapabilities request. More...
 
QgsCoordinateTransformContext transformContext () const
 Returns the layer data provider coordinate transform context or a default transform context if the layer does not have a valid data provider. More...
 
QgsMapLayerType type () const
 Returns the type of the layer. More...
 
QUndoStack * undoStack ()
 Returns pointer to layer's undo stack. More...
 
QUndoStack * undoStackStyles ()
 Returns pointer to layer's style undo stack. More...
 
QgsRectangle wgs84Extent (bool forceRecalculate=false) const
 Returns the WGS84 extent (EPSG:4326) of the layer according to ReadFlag::FlagTrustLayerMetadata. More...
 
bool writeLayerXml (QDomElement &layerElement, QDomDocument &document, const QgsReadWriteContext &context) const
 Stores state in DOM node. More...
 
virtual bool writeStyle (QDomNode &node, QDomDocument &doc, QString &errorMessage, const QgsReadWriteContext &context, StyleCategories categories=AllStyleCategories) const
 Write just the symbology information for the layer into the document. More...
 
virtual bool writeSymbology (QDomNode &node, QDomDocument &doc, QString &errorMessage, const QgsReadWriteContext &context, StyleCategories categories=AllStyleCategories) const =0
 Write the style for the layer into the docment provided. More...
 

Static Public Member Functions

static QString extensionPropertyType (PropertyType type)
 Returns the extension of a Property. More...
 
static QString formatLayerName (const QString &name)
 A convenience function to capitalize and format a layer name. More...
 
static QString generateId (const QString &layerName)
 Generates an unique identifier for this layer, the generate ID is prefixed by layerName. More...
 

Protected Member Functions

void appendError (const QgsErrorMessage &error)
 Add error message. More...
 
void clone (QgsMapLayer *layer) const
 Copies attributes like name, short name, ... More...
 
QString crsHtmlMetadata () const
 Returns a HTML fragment containing the layer's CRS metadata, for use in the htmlMetadata() method. More...
 
virtual QString decodedSource (const QString &source, const QString &dataProvider, const QgsReadWriteContext &context) const
 Called by readLayerXML(), used by derived classes to decode provider's specific data source from project files. More...
 
virtual QString encodedSource (const QString &source, const QgsReadWriteContext &context) const
 Called by writeLayerXML(), used by derived classes to encode provider's specific data source to project files. More...
 
Q_DECL_DEPRECATED bool hasDependencyCycle (const QSet< QgsMapLayerDependency > &) const
 Checks whether a new set of dependencies will introduce a cycle this method is now deprecated and always return false, because circular dependencies are now correctly managed. More...
 
void invalidateWgs84Extent ()
 Invalidates the WGS84 extent. More...
 
void readCommonStyle (const QDomElement &layerElement, const QgsReadWriteContext &context, StyleCategories categories=AllStyleCategories)
 Read style data common to all layer types. More...
 
void readCustomProperties (const QDomNode &layerNode, const QString &keyStartsWith=QString())
 Read custom properties from project file. More...
 
void readStyleManager (const QDomNode &layerNode)
 Read style manager's configuration (if any). To be called by subclasses. More...
 
virtual bool readXml (const QDomNode &layer_node, QgsReadWriteContext &context)
 Called by readLayerXML(), used by children to read state specific to them from project files. More...
 
void setError (const QgsError &error)
 Sets error message. More...
 
virtual void setExtent (const QgsRectangle &rect)
 Sets the extent. More...
 
void setProviderType (const QString &providerType)
 Sets the providerType (provider key) More...
 
void setValid (bool valid)
 Sets whether layer is valid or not. More...
 
void writeCommonStyle (QDomElement &layerElement, QDomDocument &document, const QgsReadWriteContext &context, StyleCategories categories=AllStyleCategories) const
 Write style data common to all layer types. More...
 
void writeCustomProperties (QDomNode &layerNode, QDomDocument &doc) const
 Write custom properties to project file. More...
 
void writeStyleManager (QDomNode &layerNode, QDomDocument &doc) const
 Write style manager's configuration (if exists). To be called by subclasses. More...
 
virtual bool writeXml (QDomNode &layer_node, QDomDocument &document, const QgsReadWriteContext &context) const
 Called by writeLayerXML(), used by children to write state specific to them to project files. More...
 

Protected Attributes

QString mAbstract
 Description of the layer. More...
 
QString mAttribution
 Attribution of the layer. More...
 
QString mAttributionUrl
 
int mBlockStyleChangedSignal = 0
 If non-zero, the styleChanged signal should not be emitted. More...
 
QString mDataSource
 Data source description string, varies by layer type. More...
 
QString mDataUrl
 DataUrl of the layer. More...
 
QString mDataUrlFormat
 
QSet< QgsMapLayerDependencymDependencies
 List of layers that may modify this layer on modification. More...
 
QgsError mError
 Error. More...
 
bool mIsRefreshOnNofifyEnabled = false
 
QString mKeywordList
 
QString mLayerName
 Name of the layer - used for display. More...
 
double mLayerOpacity = 1.0
 Layer opacity. More...
 
QString mLegendUrl
 WMS legend. More...
 
QString mLegendUrlFormat
 
QString mMetadataUrl
 MetadataUrl of the layer. More...
 
QString mMetadataUrlFormat
 
QString mMetadataUrlType
 
QString mProviderKey
 Data provider key (name of the data provider) More...
 
QgsMapLayer::ReadFlags mReadFlags = QgsMapLayer::ReadFlags()
 Read flags. It's up to the subclass to respect these when restoring state from XML. More...
 
QString mRefreshOnNofifyMessage
 
QString mShortName
 
bool mShouldValidateCrs = true
 true if the layer's CRS should be validated and invalid CRSes are not permitted. More...
 
QString mTitle
 
bool mValid = false
 Indicates if the layer is valid and can be drawn. More...
 

Properties

int autoRefreshInterval
 
QgsCoordinateReferenceSystem crs
 
bool isValid
 
QgsLayerMetadata metadata
 
QString name
 
double opacity
 
QgsMapLayerType type
 

Friends

class QgsVectorLayer
 

Detailed Description

Base class for all map layer types.

This is the base class for all map layer types (vector, raster).

Definition at line 69 of file qgsmaplayer.h.

Member Enumeration Documentation

◆ LayerFlag

Flags for the map layer.

Note
Flags are options specified by the user used for the UI but are not preventing any API call.
Since
QGIS 3.4
Enumerator
Identifiable 

If the layer is identifiable using the identify map tool and as a WMS layer.

Removable 

If the layer can be removed from the project. The layer will not be removable from the legend menu entry but can still be removed with an API call.

Searchable 

Only for vector-layer, determines if the layer is used in the 'search all layers' locator.

Private 

Determines if the layer is meant to be exposed to the GUI, i.e. visible in the layer legend tree.

Definition at line 137 of file qgsmaplayer.h.

◆ PropertyType

Maplayer has a style and a metadata property.

Since
QGIS 3.0
Enumerator
Style 
Metadata 

Definition at line 126 of file qgsmaplayer.h.

◆ ReadFlag

Flags which control project read behavior.

Since
QGIS 3.10
Enumerator
FlagDontResolveLayers 

Don't resolve layer paths or create data providers for layers.

FlagTrustLayerMetadata 

Trust layer metadata. Improves layer load time by skipping expensive checks like primary key unicity, geometry type and srid and by using estimated metadata on layer load. Since QGIS 3.16.

FlagReadExtentFromXml 

Read extent from xml and skip get extent from provider.

Definition at line 578 of file qgsmaplayer.h.

◆ StyleCategory

Categories of style to distinguish appropriate sections for import/export.

Since
QGIS 3.4
Enumerator
LayerConfiguration 

General configuration: identifiable, removable, searchable, display expression, read-only.

Symbology 

Symbology.

Symbology3D 

3D symbology

Labeling 

Labeling.

Fields 

Aliases, widgets, WMS/WFS, expressions, constraints, virtual fields.

Forms 

Feature form.

Actions 

Actions.

MapTips 

Map tips.

Diagrams 

Diagrams.

AttributeTable 

Attribute table settings: choice and order of columns, conditional styling.

Rendering 

Rendering: scale visibility, simplify method, opacity.

CustomProperties 

Custom properties (by plugins for instance)

GeometryOptions 

Geometry validation configuration.

Relations 

Relations.

Temporal 

Temporal properties (since QGIS 3.14)

Legend 

Legend settings (since QGIS 3.16)

Elevation 

Elevation settings (since QGIS 3.18)

Notes 

Layer user notes (since QGIS 3.20)

AllStyleCategories 

Definition at line 152 of file qgsmaplayer.h.

Constructor & Destructor Documentation

◆ QgsMapLayer() [1/2]

QgsMapLayer::QgsMapLayer ( QgsMapLayerType  type = QgsMapLayerType::VectorLayer,
const QString &  name = QString(),
const QString &  source = QString() 
)

Constructor for QgsMapLayer.

Parameters
typelayer type
namedisplay name for the layer
sourcedatasource of layer

Definition at line 80 of file qgsmaplayer.cpp.

◆ ~QgsMapLayer()

QgsMapLayer::~QgsMapLayer ( )
override

Definition at line 97 of file qgsmaplayer.cpp.

◆ QgsMapLayer() [2/2]

QgsMapLayer::QgsMapLayer ( QgsMapLayer const &  )
delete

QgsMapLayer cannot be copied.

Member Function Documentation

◆ abstract()

QString QgsMapLayer::abstract ( ) const
inline

Returns the abstract of the layer used by QGIS Server in GetCapabilities request.

Returns
the layer abstract
See also
setAbstract()

Definition at line 303 of file qgsmaplayer.h.

◆ accept()

bool QgsMapLayer::accept ( QgsStyleEntityVisitorInterface visitor) const
virtual

Accepts the specified symbology visitor, causing it to visit all symbols associated with the layer.

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

Since
QGIS 3.10

Reimplemented in QgsRasterLayer.

Definition at line 2060 of file qgsmaplayer.cpp.

◆ appendError()

void QgsMapLayer::appendError ( const QgsErrorMessage error)
inlineprotected

Add error message.

Definition at line 1649 of file qgsmaplayer.h.

◆ attribution()

QString QgsMapLayer::attribution ( ) const
inline

Returns the attribution of the layer used by QGIS Server in GetCapabilities request.

Attribution indicates the provider of a layer or collection of layers.

Returns
the layer attribution
See also
setAttribution()

Definition at line 377 of file qgsmaplayer.h.

◆ attributionUrl()

QString QgsMapLayer::attributionUrl ( ) const
inline

Returns the attribution URL of the layer used by QGIS Server in GetCapabilities request.

Attribution indicates the provider of a layer or collection of layers.

Returns
the layer attribution URL
See also
setAttributionUrl()

Definition at line 395 of file qgsmaplayer.h.

◆ autoRefreshInterval()

int QgsMapLayer::autoRefreshInterval ( ) const

Returns the auto refresh interval (in milliseconds).

Note that auto refresh is only active when hasAutoRefreshEnabled() is true.

See also
hasAutoRefreshEnabled()
setAutoRefreshInterval()
Since
QGIS 3.0

Definition at line 743 of file qgsmaplayer.cpp.

◆ autoRefreshIntervalChanged

void QgsMapLayer::autoRefreshIntervalChanged ( int  interval)
signal

Emitted when the auto refresh interval changes.

See also
setAutoRefreshInterval()
Since
QGIS 3.0

◆ beforeResolveReferences

void QgsMapLayer::beforeResolveReferences ( QgsProject project)
signal

Emitted when all layers are loaded and references can be resolved, just before the references of this layer are resolved.

Since
QGIS 3.10

◆ blendMode()

QPainter::CompositionMode QgsMapLayer::blendMode ( ) const

Returns the current blending mode for a layer.

See also
setBlendMode()

Definition at line 223 of file qgsmaplayer.cpp.

◆ blendModeChanged

void QgsMapLayer::blendModeChanged ( QPainter::CompositionMode  blendMode)
signal

Signal emitted when the blend mode is changed, through QgsMapLayer::setBlendMode()

◆ clone() [1/2]

virtual QgsMapLayer* QgsMapLayer::clone ( ) const
pure virtual

Returns a new instance equivalent to this one except for the id which is still unique.

Returns
a new layer instance
Since
QGIS 3.0

Implemented in QgsPluginLayer, QgsVectorTileLayer, QgsVectorLayer, QgsRasterLayer, QgsPointCloudLayer, QgsMeshLayer, and QgsAnnotationLayer.

◆ clone() [2/2]

void QgsMapLayer::clone ( QgsMapLayer layer) const
protected

Copies attributes like name, short name, ...

into another layer.

Parameters
layerThe copy recipient
Since
QGIS 3.0

Definition at line 104 of file qgsmaplayer.cpp.

◆ configChanged

void QgsMapLayer::configChanged ( )
signal

Emitted whenever the configuration is changed.

The project listens to this signal to be marked as dirty.

◆ createMapRenderer()

virtual QgsMapLayerRenderer* QgsMapLayer::createMapRenderer ( QgsRenderContext rendererContext)
pure virtual

Returns new instance of QgsMapLayerRenderer that will be used for rendering of given context.

Since
QGIS 2.4

Implemented in QgsVectorTileLayer, QgsRasterLayer, QgsPointCloudLayer, QgsMeshLayer, QgsAnnotationLayer, and QgsVectorLayer.

◆ crs()

QgsCoordinateReferenceSystem QgsMapLayer::crs ( ) const

Returns the layer's spatial reference system.

Since
QGIS 1.4

Definition at line 821 of file qgsmaplayer.cpp.

◆ crsChanged

void QgsMapLayer::crsChanged ( )
signal

Emit a signal that layer's CRS has been reset.

◆ crsHtmlMetadata()

QString QgsMapLayer::crsHtmlMetadata ( ) const
protected

Returns a HTML fragment containing the layer's CRS metadata, for use in the htmlMetadata() method.

Note
Not available in Python bindings.
Since
QGIS 3.20

Definition at line 2175 of file qgsmaplayer.cpp.

◆ customProperties()

const QgsObjectCustomProperties & QgsMapLayer::customProperties ( ) const

Read all custom properties from layer.

Properties are stored in a map and saved in project file.

See also
setCustomProperties
Since
QGIS 3.14

Definition at line 1872 of file qgsmaplayer.cpp.

◆ customProperty()

QVariant QgsMapLayer::customProperty ( const QString &  value,
const QVariant &  defaultValue = QVariant() 
) const

Read a custom property from layer.

Properties are stored in a map and saved in project file.

See also
setCustomProperty()

Definition at line 1877 of file qgsmaplayer.cpp.

◆ customPropertyChanged

void QgsMapLayer::customPropertyChanged ( const QString &  key)
signal

Emitted when a custom property of the layer has been changed or removed.

Since
QGIS 3.18

◆ customPropertyKeys()

QStringList QgsMapLayer::customPropertyKeys ( ) const

Returns list of all keys within custom properties.

Properties are stored in a map and saved in project file.

See also
customProperty()
Since
QGIS 3.0

Definition at line 1853 of file qgsmaplayer.cpp.

◆ dataChanged

void QgsMapLayer::dataChanged ( )
signal

Data of layer changed.

◆ dataProvider() [1/2]

QgsDataProvider * QgsMapLayer::dataProvider ( )
virtual

Returns the layer's data provider, it may be nullptr.

Reimplemented in QgsRasterLayer, QgsPluginLayer, QgsPointCloudLayer, QgsMeshLayer, and QgsVectorLayer.

Definition at line 180 of file qgsmaplayer.cpp.

◆ dataProvider() [2/2]

const QgsDataProvider * QgsMapLayer::dataProvider ( ) const
virtual

Returns the layer's data provider in a const-correct manner, it may be nullptr.

Note
not available in Python bindings

Reimplemented in QgsRasterLayer, QgsPluginLayer, QgsPointCloudLayer, QgsMeshLayer, and QgsVectorLayer.

Definition at line 185 of file qgsmaplayer.cpp.

◆ dataSourceChanged

void QgsMapLayer::dataSourceChanged ( )
signal

Emitted whenever the layer's data source has been changed.

See also
setDataSource()
Since
QGIS 3.5

◆ dataUrl()

QString QgsMapLayer::dataUrl ( ) const
inline

Returns the DataUrl of the layer used by QGIS Server in GetCapabilities request.

DataUrl is a a link to the underlying data represented by a particular layer.

Returns
the layer DataUrl
See also
setDataUrl()

Definition at line 339 of file qgsmaplayer.h.

◆ dataUrlFormat()

QString QgsMapLayer::dataUrlFormat ( ) const
inline

Returns the DataUrl format of the layer used by QGIS Server in GetCapabilities request.

DataUrl is a a link to the underlying data represented by a particular layer.

Returns
the layer DataUrl format
See also
setDataUrlFormat()

Definition at line 357 of file qgsmaplayer.h.

◆ decodedSource()

QString QgsMapLayer::decodedSource ( const QString &  source,
const QString &  dataProvider,
const QgsReadWriteContext context 
) const
protectedvirtual

Called by readLayerXML(), used by derived classes to decode provider's specific data source from project files.

Typically resolving absolute or relative paths, usernames and passwords or drivers prefixes ("HDF5:")

Parameters
sourcedata source to decode, typically read from layer's DOM element "datasource"
dataProviderstring identification of data provider (e.g. "ogr"), typically read from layer's DOM element
contextreading context (e.g. for conversion between relative and absolute paths)
Returns
decoded source, typically to be used as the layer's datasource
Since
QGIS 3.2

Reimplemented in QgsRasterLayer, QgsMeshLayer, QgsVectorTileLayer, QgsVectorLayer, and QgsPointCloudLayer.

Definition at line 669 of file qgsmaplayer.cpp.

◆ dependencies()

QSet< QgsMapLayerDependency > QgsMapLayer::dependencies ( ) const
virtual

Gets the list of dependencies.

This includes data dependencies set by the user (

See also
setDataDependencies) as well as dependencies given by the provider
Returns
a set of QgsMapLayerDependency
Since
QGIS 3.0

Reimplemented in QgsVectorLayer.

Definition at line 2070 of file qgsmaplayer.cpp.

◆ dependenciesChanged

void QgsMapLayer::dependenciesChanged ( )
signal

Emitted when dependencies are changed.

◆ elevationProperties()

virtual QgsMapLayerElevationProperties* QgsMapLayer::elevationProperties ( )
inlinevirtual

Returns the layer's elevation properties.

This may be nullptr, depending on the layer type.

Since
QGIS 3.18

Reimplemented in QgsPointCloudLayer.

Definition at line 1265 of file qgsmaplayer.h.

◆ emitStyleChanged

void QgsMapLayer::emitStyleChanged ( )
slot

Triggers an emission of the styleChanged() signal.

Since
QGIS 2.16

Definition at line 2018 of file qgsmaplayer.cpp.

◆ encodedSource()

QString QgsMapLayer::encodedSource ( const QString &  source,
const QgsReadWriteContext context 
) const
protectedvirtual

Called by writeLayerXML(), used by derived classes to encode provider's specific data source to project files.

Typically resolving absolute or relative paths, usernames and passwords or drivers prefixes ("HDF5:")

Parameters
sourcedata source to encode, typically QgsMapLayer::source()
contextwriting context (e.g. for conversion between relative and absolute paths)
Returns
encoded source, typically to be written in the DOM element "datasource"
Since
QGIS 3.2

Reimplemented in QgsRasterLayer, QgsPointCloudLayer, QgsMeshLayer, QgsVectorTileLayer, and QgsVectorLayer.

Definition at line 663 of file qgsmaplayer.cpp.

◆ error()

QgsError QgsMapLayer::error ( ) const
virtual

Gets current status error.

This error describes some principal problem for which layer cannot work and thus is not valid. It is not last error after accessing data by draw() etc.

Definition at line 1892 of file qgsmaplayer.cpp.

◆ exportNamedMetadata()

void QgsMapLayer::exportNamedMetadata ( QDomDocument &  doc,
QString &  errorMsg 
) const

Export the current metadata of this layer as named metadata in a QDomDocument.

Parameters
docthe target QDomDocument
errorMsgthis QString will be initialized on error
Since
QGIS 3.0

Definition at line 1156 of file qgsmaplayer.cpp.

◆ exportNamedStyle()

void QgsMapLayer::exportNamedStyle ( QDomDocument &  doc,
QString &  errorMsg,
const QgsReadWriteContext context = QgsReadWriteContext(),
QgsMapLayer::StyleCategories  categories = QgsMapLayer::AllStyleCategories 
) const
virtual

Export the properties of this layer as named style in a QDomDocument.

Parameters
docthe target QDomDocument
errorMsgthis QString will be initialized on error
contextread write context
categoriesthe style categories to export during the execution of writeSymbology

Definition at line 1175 of file qgsmaplayer.cpp.

◆ exportSldStyle()

void QgsMapLayer::exportSldStyle ( QDomDocument &  doc,
QString &  errorMsg 
) const
virtual

Export the properties of this layer as SLD style in a QDomDocument.

Parameters
docthe target QDomDocument
errorMsgthis QString will be initialized on error during the execution of writeSymbology

Definition at line 1463 of file qgsmaplayer.cpp.

◆ extensionPropertyType()

QString QgsMapLayer::extensionPropertyType ( QgsMapLayer::PropertyType  type)
static

Returns the extension of a Property.

Returns
The extension
Since
QGIS 3.0

Definition at line 67 of file qgsmaplayer.cpp.

◆ extent()

QgsRectangle QgsMapLayer::extent ( ) const
virtual

Returns the extent of the layer.

Reimplemented in QgsPointCloudLayer, QgsMeshLayer, QgsAnnotationLayer, and QgsVectorLayer.

Definition at line 208 of file qgsmaplayer.cpp.

◆ flags()

QgsMapLayer::LayerFlags QgsMapLayer::flags ( ) const

Returns the flags for this layer.

Note
Flags are options specified by the user used for the UI but are not preventing any API call. For instance, even if the Removable flag is not set, the layer can still be removed with the API but the action will not be listed in the legend menu.
Since
QGIS 3.4

Definition at line 145 of file qgsmaplayer.cpp.

◆ flagsChanged

void QgsMapLayer::flagsChanged ( )
signal

Emitted when layer's flags have been modified.

See also
setFlags()
flags()
Since
QGIS 3.4

◆ formatLayerName()

QString QgsMapLayer::formatLayerName ( const QString &  name)
static

A convenience function to capitalize and format a layer name.

Since
QGIS 3.0

Definition at line 846 of file qgsmaplayer.cpp.

◆ generateId()

QString QgsMapLayer::generateId ( const QString &  layerName)
static

Generates an unique identifier for this layer, the generate ID is prefixed by layerName.

Since
QGIS 3.8

Definition at line 2044 of file qgsmaplayer.cpp.

◆ hasAutoRefreshEnabled()

bool QgsMapLayer::hasAutoRefreshEnabled ( ) const

Returns true if auto refresh is enabled for the layer.

See also
autoRefreshInterval()
setAutoRefreshEnabled()
Since
QGIS 3.0

Definition at line 738 of file qgsmaplayer.cpp.

◆ hasDependencyCycle()

Q_DECL_DEPRECATED bool QgsMapLayer::hasDependencyCycle ( const QSet< QgsMapLayerDependency > &  ) const
inlineprotected

Checks whether a new set of dependencies will introduce a cycle this method is now deprecated and always return false, because circular dependencies are now correctly managed.

Deprecated:
since QGIS 3.10

Definition at line 1705 of file qgsmaplayer.h.

◆ hasScaleBasedVisibility()

bool QgsMapLayer::hasScaleBasedVisibility ( ) const

Returns whether scale based visibility is enabled for the layer.

Returns
true if scale based visibility is enabled
See also
minimumScale()
maximumScale()
setScaleBasedVisibility()
isInScaleRange()

Definition at line 733 of file qgsmaplayer.cpp.

◆ htmlMetadata()

QString QgsMapLayer::htmlMetadata ( ) const
virtual

Obtain a formatted HTML string containing assorted metadata for this layer.

Since
QGIS 3.0

Reimplemented in QgsVectorTileLayer, QgsRasterLayer, QgsPointCloudLayer, QgsMeshLayer, and QgsVectorLayer.

Definition at line 2008 of file qgsmaplayer.cpp.

◆ id()

QString QgsMapLayer::id ( ) const

Returns the layer's unique ID, which is used to access this layer from QgsProject.

Definition at line 159 of file qgsmaplayer.cpp.

◆ importNamedMetadata()

bool QgsMapLayer::importNamedMetadata ( QDomDocument &  document,
QString &  errorMessage 
)

Import the metadata of this layer from a QDomDocument.

Parameters
documentsource QDomDocument
errorMessagethis QString will be initialized on error
Returns
true on success
Since
QGIS 3.0

Definition at line 1102 of file qgsmaplayer.cpp.

◆ importNamedStyle()

bool QgsMapLayer::importNamedStyle ( QDomDocument &  doc,
QString &  errorMsg,
QgsMapLayer::StyleCategories  categories = QgsMapLayer::AllStyleCategories 
)
virtual

Import the properties of this layer from a QDomDocument.

Parameters
docsource QDomDocument
errorMsgthis QString will be initialized on error during the execution of readSymbology
categoriesthe style categories to import
Returns
true on success
Since
QGIS 2.8

Definition at line 1114 of file qgsmaplayer.cpp.

◆ invalidateWgs84Extent()

void QgsMapLayer::invalidateWgs84Extent ( )
protected

Invalidates the WGS84 extent.

If FlagTrustLayerMetadata is enabled, the extent is not invalidated because we want to trust metadata whatever happens.

Since
QGIS 3.20

Definition at line 2166 of file qgsmaplayer.cpp.

◆ isEditable()

bool QgsMapLayer::isEditable ( ) const
virtual

Returns true if the layer can be edited.

Reimplemented in QgsVectorLayer.

Definition at line 1899 of file qgsmaplayer.cpp.

◆ isInScaleRange()

bool QgsMapLayer::isInScaleRange ( double  scale) const

Tests whether the layer should be visible at the specified scale.

The scale value indicates the scale denominator, e.g. 1000.0 for a 1:1000 map.

Returns
true if the layer is visible at the given scale.
See also
minimumScale()
maximumScale()
hasScaleBasedVisibility()
Since
QGIS 2.16

Definition at line 726 of file qgsmaplayer.cpp.

◆ isRefreshOnNotifyEnabled()

bool QgsMapLayer::isRefreshOnNotifyEnabled ( ) const
inline

Returns true if the refresh on provider nofification is enabled.

Since
QGIS 3.0

Definition at line 1215 of file qgsmaplayer.h.

◆ isSpatial()

bool QgsMapLayer::isSpatial ( ) const
virtual

Returns true if the layer is considered a spatial layer, ie it has some form of geometry associated with it.

Since
QGIS 2.16

Reimplemented in QgsRasterLayer, and QgsVectorLayer.

Definition at line 1904 of file qgsmaplayer.cpp.

◆ isTemporary()

bool QgsMapLayer::isTemporary ( ) const
virtual

Returns true if the layer is considered a temporary layer.

These include memory-only layers such as those created by the "memory" data provider, layers stored inside a local temporary folder (such as the "/tmp" folder on Linux) or layer with temporary data (as temporary mesh layer dataset)

Since
QGIS 3.10.1

Definition at line 1909 of file qgsmaplayer.cpp.

◆ isValid()

bool QgsMapLayer::isValid ( ) const

Returns the status of the layer.

An invalid layer is one which has a bad datasource or other problem. Child classes set this flag when initialized.

Returns
true if the layer is valid and can be accessed

Definition at line 713 of file qgsmaplayer.cpp.

◆ isValidChanged

void QgsMapLayer::isValidChanged ( )
signal

Emitted when the validity of this layer changed.

Since
QGIS 3.16

◆ keywordList()

QString QgsMapLayer::keywordList ( ) const
inline

Returns the keyword list of the layer used by QGIS Server in GetCapabilities request.

Returns
the layer keyword list
See also
setKeywordList()

Definition at line 319 of file qgsmaplayer.h.

◆ legend()

QgsMapLayerLegend * QgsMapLayer::legend ( ) const

Can be nullptr.

Since
QGIS 2.6

Definition at line 1960 of file qgsmaplayer.cpp.

◆ legendChanged

void QgsMapLayer::legendChanged ( )
signal

Signal emitted when legend of the layer has changed.

Since
QGIS 2.6

◆ legendUrl()

QString QgsMapLayer::legendUrl ( ) const
inline

Returns the URL for the layer's legend.

Definition at line 1043 of file qgsmaplayer.h.

◆ legendUrlFormat()

QString QgsMapLayer::legendUrlFormat ( ) const
inline

Returns the format for a URL based layer legend.

Definition at line 1053 of file qgsmaplayer.h.

◆ loadDefaultMetadata()

QString QgsMapLayer::loadDefaultMetadata ( bool &  resultFlag)
virtual

Retrieve the default metadata for this layer if one exists (either as a .qmd file on disk or as a record in the users metadata table in their personal qgis.db)

Parameters
resultFlaga reference to a flag that will be set to false if we did not manage to load the default metadata.
Returns
a QString with any status messages
Since
QGIS 3.0

Reimplemented in QgsVectorTileLayer.

Definition at line 929 of file qgsmaplayer.cpp.

◆ loadDefaultStyle()

QString QgsMapLayer::loadDefaultStyle ( bool &  resultFlag)
virtual

Retrieve the default style for this layer if one exists (either as a .qml file on disk or as a record in the users style table in their personal qgis.db)

Parameters
resultFlaga reference to a flag that will be set to false if we did not manage to load the default style.
Returns
a QString with any status messages
See also
also loadNamedStyle();

Reimplemented in QgsVectorTileLayer, QgsVectorLayer, and QgsPointCloudLayer.

Definition at line 939 of file qgsmaplayer.cpp.

◆ loadNamedMetadata()

QString QgsMapLayer::loadNamedMetadata ( const QString &  uri,
bool &  resultFlag 
)
virtual

Retrieve a named metadata for this layer if one exists (either as a .qmd file on disk or as a record in the users style table in their personal qgis.db)

Parameters
uri- the file name or other URI for the metadata file. First an attempt will be made to see if this is a file and load that, if that fails the qgis.db metadata table will be consulted to see if there is a metadata who's key matches the URI.
resultFlaga reference to a flag that will be set to false if we did not manage to load the default metadata.
Returns
a QString with any status messages
Since
QGIS 3.0

Definition at line 1222 of file qgsmaplayer.cpp.

◆ loadNamedMetadataFromDatabase()

bool QgsMapLayer::loadNamedMetadataFromDatabase ( const QString &  db,
const QString &  uri,
QString &  qmd 
)

Retrieve a named metadata for this layer from a sqlite database.

Parameters
dbpath to sqlite database
uriuri for table
qmdwill be set to QMD xml metadata content from database
Returns
true if style was successfully loaded
Since
QGIS 3.0

Definition at line 944 of file qgsmaplayer.cpp.

◆ loadNamedStyle()

QString QgsMapLayer::loadNamedStyle ( const QString &  uri,
bool &  resultFlag,
QgsMapLayer::StyleCategories  categories = QgsMapLayer::AllStyleCategories 
)
virtual

Retrieve a named style for this layer if one exists (either as a .qml file on disk or as a record in the users style table in their personal qgis.db)

Parameters
uri- the file name or other URI for the style file. First an attempt will be made to see if this is a file and load that, if that fails the qgis.db styles table will be consulted to see if there is a style who's key matches the URI.
resultFlaga reference to a flag that will be set to false if we did not manage to load the default style.
categoriesthe style categories to be loaded.
Returns
a QString with any status messages
See also
also loadDefaultStyle ();

Reimplemented in QgsVectorLayer.

Definition at line 1005 of file qgsmaplayer.cpp.

◆ loadNamedStyleFromDatabase()

bool QgsMapLayer::loadNamedStyleFromDatabase ( const QString &  db,
const QString &  uri,
QString &  qml 
)
virtual

Retrieve a named style for this layer from a sqlite database.

Parameters
dbpath to sqlite database
uriuri for table
qmlwill be set to QML style content from database
Returns
true if style was successfully loaded

Definition at line 949 of file qgsmaplayer.cpp.

◆ loadSldStyle()

QString QgsMapLayer::loadSldStyle ( const QString &  uri,
bool &  resultFlag 
)
virtual

Attempts to style the layer using the formatting from an SLD type file.

Parameters
uriuri of source SLD file
resultFlaga reference to a flag that will be set to false if the SLD file could not be loaded
Returns
a string with any status or error messages
See also
saveSldStyle()

Definition at line 1605 of file qgsmaplayer.cpp.

◆ maximumScale()

double QgsMapLayer::maximumScale ( ) const

Returns the maximum map scale (i.e.

most "zoomed in" scale) at which the layer will be visible. The scale value indicates the scale denominator, e.g. 1000.0 for a 1:1000 map. A scale of 0 indicates no maximum scale visibility.

Note
Scale based visibility is only used if setScaleBasedVisibility() is set to true.
See also
setMaximumScale()
minimumScale()
hasScaleBasedVisibility()
isInScaleRange()

Definition at line 782 of file qgsmaplayer.cpp.

◆ metadata()

const QgsLayerMetadata & QgsMapLayer::metadata ( ) const
virtual

Returns a reference to the layer's metadata store.

See also
setMetadata()
metadataChanged()
Since
QGIS 3.0

Definition at line 772 of file qgsmaplayer.cpp.

◆ metadataChanged

void QgsMapLayer::metadataChanged ( )
signal

Emitted when the layer's metadata is changed.

See also
setMetadata()
metadata()
Since
QGIS 3.0

◆ metadataUri()

QString QgsMapLayer::metadataUri ( ) const
virtual

Retrieve the metadata URI for this layer (either as a .qmd file on disk or as a record in the users style table in their personal qgis.db)

Returns
a QString with the metadata file name
Since
QGIS 3.0

Definition at line 897 of file qgsmaplayer.cpp.

◆ metadataUrl()

QString QgsMapLayer::metadataUrl ( ) const
inline

Returns the metadata URL of the layer used by QGIS Server in GetCapabilities request.

MetadataUrl is a a link to the detailed, standardized metadata about the data.

Returns
the layer metadata URL
See also
setMetadataUrl()

Definition at line 415 of file qgsmaplayer.h.

◆ metadataUrlFormat()

QString QgsMapLayer::metadataUrlFormat ( ) const
inline

Returns the metadata format of the layer used by QGIS Server in GetCapabilities request.

MetadataUrlType indicates how the metadata is structured.

Returns
the layer metadata format
See also
setMetadataUrlFormat()

Definition at line 451 of file qgsmaplayer.h.

◆ metadataUrlType()

QString QgsMapLayer::metadataUrlType ( ) const
inline

Returns the metadata type of the layer used by QGIS Server in GetCapabilities request.

MetadataUrlType indicates the standard to which the metadata complies.

Returns
the layer metadata type
See also
setMetadataUrlType()

Definition at line 433 of file qgsmaplayer.h.

◆ minimumScale()

double QgsMapLayer::minimumScale ( ) const

Returns the minimum map scale (i.e.

most "zoomed out" scale) at which the layer will be visible. The scale value indicates the scale denominator, e.g. 1000.0 for a 1:1000 map. A scale of 0 indicates no minimum scale visibility.

Note
Scale based visibility is only used if setScaleBasedVisibility() is set to true.
See also
setMinimumScale()
maximumScale()
hasScaleBasedVisibility()
isInScaleRange()

Definition at line 798 of file qgsmaplayer.cpp.

◆ name()

QString QgsMapLayer::name ( ) const

Returns the display name of the layer.

See also
setName()

Definition at line 174 of file qgsmaplayer.cpp.

◆ nameChanged

void QgsMapLayer::nameChanged ( )
signal

Emitted when the name has been changed.

Since
QGIS 2.16

◆ opacity()

double QgsMapLayer::opacity ( ) const
virtual

Returns the opacity for the layer, where opacity is a value between 0 (totally transparent) and 1.0 (fully opaque).

See also
setOpacity()
opacityChanged()
Note
Prior to QGIS 3.18, this method was available for vector layers only
Since
QGIS 3.18

Reimplemented in QgsRasterLayer.

Definition at line 237 of file qgsmaplayer.cpp.

◆ opacityChanged

void QgsMapLayer::opacityChanged ( double  opacity)
signal

Emitted when the layer's opacity is changed, where opacity is a value between 0 (transparent) and 1 (opaque).

See also
setOpacity()
opacity()
Note
Prior to QGIS 3.18, this signal was available for vector layers only
Since
QGIS 3.18

◆ operator=()

QgsMapLayer& QgsMapLayer::operator= ( QgsMapLayer const &  )
delete

QgsMapLayer cannot be copied.

◆ originalXmlProperties()

QString QgsMapLayer::originalXmlProperties ( ) const

Returns the XML properties of the original layer as they were when the layer was first read from the project file.

In case of new layers this is normally empty.

The storage format for the XML is qlr

Since
QGIS 3.6

Definition at line 2034 of file qgsmaplayer.cpp.

◆ project

QgsProject * QgsMapLayer::project ( ) const
slot

Returns the parent project if this map layer is added to a project.

Otherwise returns nullptr

Since
QGIS 3.18

Definition at line 2110 of file qgsmaplayer.cpp.

◆ providerType()

QString QgsMapLayer::providerType ( ) const

Returns the provider type (provider key) for this layer.

Definition at line 1746 of file qgsmaplayer.cpp.

◆ publicSource()

QString QgsMapLayer::publicSource ( ) const

Gets a version of the internal layer definition that has sensitive bits removed (for example, the password).

This function should be used when displaying the source name for general viewing.

See also
source()

Definition at line 195 of file qgsmaplayer.cpp.

◆ readCommonStyle()

void QgsMapLayer::readCommonStyle ( const QDomElement &  layerElement,
const QgsReadWriteContext context,
StyleCategories  categories = AllStyleCategories 
)
protected

Read style data common to all layer types.

Since
QGIS 3.0

Definition at line 1751 of file qgsmaplayer.cpp.

◆ readCustomProperties()

void QgsMapLayer::readCustomProperties ( const QDomNode &  layerNode,
const QString &  keyStartsWith = QString() 
)
protected

Read custom properties from project file.

Parameters
layerNodenote to read from
keyStartsWithreads only properties starting with the specified string (or all if the string is empty)

Definition at line 684 of file qgsmaplayer.cpp.

◆ readLayerXml()

bool QgsMapLayer::readLayerXml ( const QDomElement &  layerElement,
QgsReadWriteContext context,
QgsMapLayer::ReadFlags  flags = QgsMapLayer::ReadFlags() 
)

Sets state from DOM document.

Parameters
layerElementThe DOM element corresponding to `‘maplayer’' tag
contextwriting context (e.g. for conversion between relative and absolute paths)
flagsoptional argument which can be used to control layer reading behavior.
Note

The DOM node corresponds to a DOM document project file XML element read by QgsProject.

This, in turn, calls readXml() (and then readSymbology()), which is overridable by sub-classes so that they can read their own specific state from the given DOM node.

Invoked by QgsProject::read().

Returns
true if successful

Definition at line 242 of file qgsmaplayer.cpp.

◆ readOnly()

bool QgsMapLayer::readOnly ( ) const
inline

Returns if this layer is read only.

Definition at line 487 of file qgsmaplayer.h.

◆ readSld()

virtual bool QgsMapLayer::readSld ( const QDomNode &  node,
QString &  errorMessage 
)
inlinevirtual

Reimplemented in QgsVectorLayer.

Definition at line 916 of file qgsmaplayer.h.

◆ readStyle()

bool QgsMapLayer::readStyle ( const QDomNode &  node,
QString &  errorMessage,
QgsReadWriteContext context,
StyleCategories  categories = AllStyleCategories 
)
virtual

Read the style for the current layer from the DOM node supplied.

Parameters
nodenode that will contain the style definition for this layer.
errorMessagereference to string that will be updated with any error messages
contextreading context (used for transform from relative to absolute paths)
categoriesthe style categories to be read
Returns
true in case of success.
Note
To be implemented in subclasses. Default implementation does nothing and returns false.
Since
QGIS 2.16

Reimplemented in QgsMeshLayer, and QgsPointCloudLayer.

Definition at line 1664 of file qgsmaplayer.cpp.

◆ readStyleManager()

void QgsMapLayer::readStyleManager ( const QDomNode &  layerNode)
protected

Read style manager's configuration (if any). To be called by subclasses.

Definition at line 694 of file qgsmaplayer.cpp.

◆ readSymbology()

virtual bool QgsMapLayer::readSymbology ( const QDomNode &  node,
QString &  errorMessage,
QgsReadWriteContext context,
StyleCategories  categories = AllStyleCategories 
)
pure virtual

Read the symbology for the current layer from the DOM node supplied.

Parameters
nodenode that will contain the symbology definition for this layer.
errorMessagereference to string that will be updated with any error messages
contextreading context (used for transform from relative to absolute paths)
categoriesthe style categories to be read
Returns
true in case of success.

Implemented in QgsVectorTileLayer, QgsPointCloudLayer, and QgsAnnotationLayer.

◆ readXml()

bool QgsMapLayer::readXml ( const QDomNode &  layer_node,
QgsReadWriteContext context 
)
protectedvirtual

Called by readLayerXML(), used by children to read state specific to them from project files.

Reimplemented in QgsVectorTileLayer, QgsPointCloudLayer, QgsAnnotationLayer, QgsRasterLayer, QgsMeshLayer, and QgsVectorLayer.

Definition at line 413 of file qgsmaplayer.cpp.

◆ recalculateExtents

void QgsMapLayer::recalculateExtents ( ) const
signal

This is used to send a request that any mapcanvas using this layer update its extents.

◆ refreshOnNotifyMessage()

QString QgsMapLayer::refreshOnNotifyMessage ( ) const
inline

Returns the message that should be notified by the provider to triggerRepaint.

Since
QGIS 3.0

Definition at line 1208 of file qgsmaplayer.h.

◆ reload()

virtual Q_INVOKABLE void QgsMapLayer::reload ( )
inlinevirtual

Synchronises with changes in the datasource.

Reimplemented in QgsRasterLayer, QgsMeshLayer, and QgsVectorLayer.

Definition at line 492 of file qgsmaplayer.h.

◆ removeCustomProperty()

void QgsMapLayer::removeCustomProperty ( const QString &  key)

Remove a custom property from layer.

Properties are stored in a map and saved in project file.

See also
setCustomProperty()

Definition at line 1882 of file qgsmaplayer.cpp.

◆ renderer3D()

QgsAbstract3DRenderer * QgsMapLayer::renderer3D ( ) const

Returns 3D renderer associated with the layer.

May be nullptr.

Since
QGIS 3.0

Definition at line 1981 of file qgsmaplayer.cpp.

◆ renderer3DChanged

void QgsMapLayer::renderer3DChanged ( )
signal

Signal emitted when 3D renderer associated with the layer has changed.

Since
QGIS 3.0

◆ rendererChanged

void QgsMapLayer::rendererChanged ( )
signal

Signal emitted when renderer is changed.

See also
styleChanged()

◆ repaintRequested

void QgsMapLayer::repaintRequested ( bool  deferredUpdate = false)
signal

By emitting this signal the layer tells that either appearance or content have been changed and any view showing the rendered layer should refresh itself.

If deferredUpdate is true then the layer will only be repainted when the canvas is next re-rendered, and will not trigger any canvas redraws itself.

◆ request3DUpdate

void QgsMapLayer::request3DUpdate ( )
signal

Signal emitted when a layer requires an update in any 3D maps.

Since
QGIS 3.18

◆ resolveReferences()

void QgsMapLayer::resolveReferences ( QgsProject project)
virtual

Resolve references to other layers (kept as layer IDs after reading XML) into layer objects.

Since
QGIS 3.0

Reimplemented in QgsVectorLayer.

Definition at line 676 of file qgsmaplayer.cpp.

◆ saveDefaultMetadata()

QString QgsMapLayer::saveDefaultMetadata ( bool &  resultFlag)
virtual

Save the current metadata of this layer as the default metadata (either as a .qmd file on disk or as a record in the users style table in their personal qgis.db)

Parameters
resultFlaga reference to a flag that will be set to false if we did not manage to save the default metadata.
Returns
a QString with any status messages
Since
QGIS 3.0

Definition at line 902 of file qgsmaplayer.cpp.

◆ saveDefaultStyle()

QString QgsMapLayer::saveDefaultStyle ( bool &  resultFlag)
virtual

Save the properties of this layer as the default style (either as a .qml file on disk or as a record in the users style table in their personal qgis.db)

Parameters
resultFlaga reference to a flag that will be set to false if we did not manage to save the default style.
Returns
a QString with any status messages
See also
loadNamedStyle() and
saveNamedStyle()

Definition at line 1212 of file qgsmaplayer.cpp.

◆ saveNamedMetadata()

QString QgsMapLayer::saveNamedMetadata ( const QString &  uri,
bool &  resultFlag 
)

Save the current metadata of this layer as a named metadata (either as a .qmd file on disk or as a record in the users style table in their personal qgis.db)

Parameters
urithe file name or other URI for the metadata file. First an attempt will be made to see if this is a file and save to that, if that fails the qgis.db metadata table will be used to create a metadata entry who's key matches the URI.
resultFlaga reference to a flag that will be set to false if we did not manage to save the default metadata.
Returns
a QString with any status messages
Since
QGIS 3.0

Definition at line 1217 of file qgsmaplayer.cpp.

◆ saveNamedStyle()

QString QgsMapLayer::saveNamedStyle ( const QString &  uri,
bool &  resultFlag,
StyleCategories  categories = AllStyleCategories 
)
virtual

Save the properties of this layer as a named style (either as a .qml file on disk or as a record in the users style table in their personal qgis.db)

Parameters
urithe file name or other URI for the style file. First an attempt will be made to see if this is a file and save to that, if that fails the qgis.db styles table will be used to create a style entry who's key matches the URI.
resultFlaga reference to a flag that will be set to false if we did not manage to save the default style.
categoriesthe style categories to be saved.
Returns
a QString with any status messages
See also
saveDefaultStyle()

Definition at line 1458 of file qgsmaplayer.cpp.

◆ saveSldStyle()

QString QgsMapLayer::saveSldStyle ( const QString &  uri,
bool &  resultFlag 
) const
virtual

Saves the properties of this layer to an SLD format file.

Parameters
uriuri of destination for exported SLD file.
resultFlaga reference to a flag that will be set to false if the SLD file could not be generated
Returns
a string with any status or error messages
See also
loadSldStyle()

Definition at line 1540 of file qgsmaplayer.cpp.

◆ setAbstract()

void QgsMapLayer::setAbstract ( const QString &  abstract)
inline

Sets the abstract of the layer used by QGIS Server in GetCapabilities request.

Returns
the layer abstract
See also
abstract()

Definition at line 295 of file qgsmaplayer.h.

◆ setAttribution()

void QgsMapLayer::setAttribution ( const QString &  attrib)
inline

Sets the attribution of the layer used by QGIS Server in GetCapabilities request.

Attribution indicates the provider of a layer or collection of layers.

Returns
the layer attribution
See also
attribution()

Definition at line 368 of file qgsmaplayer.h.

◆ setAttributionUrl()

void QgsMapLayer::setAttributionUrl ( const QString &  attribUrl)
inline

Sets the attribution URL of the layer used by QGIS Server in GetCapabilities request.

Attribution indicates the provider of a layer or collection of layers.

Returns
the layer attribution URL
See also
attributionUrl()

Definition at line 386 of file qgsmaplayer.h.

◆ setAutoRefreshEnabled()

void QgsMapLayer::setAutoRefreshEnabled ( bool  enabled)

Sets whether auto refresh is enabled for the layer.

See also
hasAutoRefreshEnabled()
setAutoRefreshInterval()
Since
QGIS 3.0

Definition at line 762 of file qgsmaplayer.cpp.

◆ setAutoRefreshInterval()

void QgsMapLayer::setAutoRefreshInterval ( int  interval)

Sets the auto refresh interval (in milliseconds) for the layer.

This will cause the layer to be automatically redrawn on a matching interval. Note that auto refresh must be enabled by calling setAutoRefreshEnabled().

Note that auto refresh triggers deferred repaints of the layer. Any map canvas must be refreshed separately in order to view the refreshed layer.

See also
autoRefreshInterval()
setAutoRefreshEnabled()
Since
QGIS 3.0

Definition at line 748 of file qgsmaplayer.cpp.

◆ setBlendMode()

void QgsMapLayer::setBlendMode ( QPainter::CompositionMode  blendMode)

Set the blending mode used for rendering a layer.

Parameters
blendModenew blending mode
See also
blendMode()

Definition at line 213 of file qgsmaplayer.cpp.

◆ setCrs()

void QgsMapLayer::setCrs ( const QgsCoordinateReferenceSystem srs,
bool  emitSignal = true 
)

Sets layer's spatial reference system.

Definition at line 826 of file qgsmaplayer.cpp.

◆ setCustomProperties()

void QgsMapLayer::setCustomProperties ( const QgsObjectCustomProperties properties)

Set custom properties for layer.

Current properties are dropped.

Since
QGIS 3.0

Definition at line 1867 of file qgsmaplayer.cpp.

◆ setCustomProperty()

void QgsMapLayer::setCustomProperty ( const QString &  key,
const QVariant &  value 
)

Set a custom property for layer.

Properties are stored in a map and saved in project file.

See also
customProperty()
removeCustomProperty()

Definition at line 1858 of file qgsmaplayer.cpp.

◆ setDataSource() [1/3]

void QgsMapLayer::setDataSource ( const QString &  dataSource,
const QString &  baseName,
const QString &  provider,
bool  loadDefaultStyleFlag = false 
)

Updates the data source of the layer.

The layer's renderer and legend will be preserved only if the geometry type of the new data source matches the current geometry type of the layer.

This method was defined in QgsVectorLayer since 2.10 and was marked as deprecated since 3.2

Parameters
dataSourcenew layer data source
baseNamebase name of the layer
providerprovider string
loadDefaultStyleFlagset to true to reset the layer's style to the default for the data source
See also
dataSourceChanged()
Since
QGIS 3.20

Definition at line 1685 of file qgsmaplayer.cpp.

◆ setDataSource() [2/3]

void QgsMapLayer::setDataSource ( const QString &  dataSource,
const QString &  baseName,
const QString &  provider,
const QgsDataProvider::ProviderOptions options,
bool  loadDefaultStyleFlag = false 
)

Updates the data source of the layer.

The layer's renderer and legend will be preserved only if the geometry type of the new data source matches the current geometry type of the layer.

Parameters
dataSourcenew layer data source
baseNamebase name of the layer
providerprovider string
optionsprovider options
loadDefaultStyleFlagset to true to reset the layer's style to the default for the data source
See also
dataSourceChanged()
Since
QGIS 3.6

Definition at line 1703 of file qgsmaplayer.cpp.

◆ setDataSource() [3/3]

void QgsMapLayer::setDataSource ( const QString &  dataSource,
const QString &  baseName,
const QString &  provider,
const QgsDataProvider::ProviderOptions options,
QgsDataProvider::ReadFlags  flags 
)

Updates the data source of the layer.

The layer's renderer and legend will be preserved only if the geometry type of the new data source matches the current geometry type of the layer.

Subclasses should override setDataSourcePrivate: default implementation does nothing.

Parameters
dataSourcenew layer data source
baseNamebase name of the layer
providerprovider string
optionsprovider options
flagsprovider read flags which control dataprovider construction like FlagTrustDataSource, FlagLoadDefaultStyle, etc
See also
dataSourceChanged()
Since
QGIS 3.20

Definition at line 1719 of file qgsmaplayer.cpp.

◆ setDataUrl()

void QgsMapLayer::setDataUrl ( const QString &  dataUrl)
inline

Sets the DataUrl of the layer used by QGIS Server in GetCapabilities request.

DataUrl is a a link to the underlying data represented by a particular layer.

Returns
the layer DataUrl
See also
dataUrl()

Definition at line 330 of file qgsmaplayer.h.

◆ setDataUrlFormat()

void QgsMapLayer::setDataUrlFormat ( const QString &  dataUrlFormat)
inline

Sets the DataUrl format of the layer used by QGIS Server in GetCapabilities request.

DataUrl is a a link to the underlying data represented by a particular layer.

Returns
the layer DataUrl format
See also
dataUrlFormat()

Definition at line 348 of file qgsmaplayer.h.

◆ setDependencies

bool QgsMapLayer::setDependencies ( const QSet< QgsMapLayerDependency > &  layers)
virtualslot

Sets the list of dependencies.

See also
dependencies()
Parameters
layersset of QgsMapLayerDependency. Only user-defined dependencies will be added
Returns
false if a dependency cycle has been detected
Since
QGIS 3.0

Reimplemented in QgsVectorLayer.

Definition at line 2075 of file qgsmaplayer.cpp.

◆ setError()

void QgsMapLayer::setError ( const QgsError error)
inlineprotected

Sets error message.

Definition at line 1651 of file qgsmaplayer.h.

◆ setExtent()

void QgsMapLayer::setExtent ( const QgsRectangle rect)
protectedvirtual

Sets the extent.

Reimplemented in QgsVectorLayer, and QgsPluginLayer.

Definition at line 2024 of file qgsmaplayer.cpp.

◆ setFlags()

void QgsMapLayer::setFlags ( QgsMapLayer::LayerFlags  flags)

Returns the flags for this layer.

Note
Flags are options specified by the user used for the UI but are not preventing any API call. For instance, even if the Removable flag is not set, the layer can still be removed with the API but the action will not be listed in the legend menu.
Since
QGIS 3.4

Definition at line 150 of file qgsmaplayer.cpp.

◆ setKeywordList()

void QgsMapLayer::setKeywordList ( const QString &  keywords)
inline

Sets the keyword list of the layer used by QGIS Server in GetCapabilities request.

Returns
the layer keyword list
See also
keywordList()

Definition at line 311 of file qgsmaplayer.h.

◆ setLayerOrder()

void QgsMapLayer::setLayerOrder ( const QStringList &  layers)
virtual

Reorders the previously selected sublayers of this layer from bottom to top.

(Useful for providers that manage their own layers, such as WMS).

Reimplemented in QgsRasterLayer.

Definition at line 808 of file qgsmaplayer.cpp.

◆ setLegend()

void QgsMapLayer::setLegend ( QgsMapLayerLegend legend)

Assign a legend controller to the map layer.

The object will be responsible for providing legend items.

Parameters
legendTakes ownership of the object. Can be nullptr.
Since
QGIS 2.6

Definition at line 1943 of file qgsmaplayer.cpp.

◆ setLegendUrl()

void QgsMapLayer::setLegendUrl ( const QString &  legendUrl)
inline

Sets the URL for the layer's legend.

Definition at line 1038 of file qgsmaplayer.h.

◆ setLegendUrlFormat()

void QgsMapLayer::setLegendUrlFormat ( const QString &  legendUrlFormat)
inline

Sets the format for a URL based layer legend.

Definition at line 1048 of file qgsmaplayer.h.

◆ setMaximumScale

void QgsMapLayer::setMaximumScale ( double  scale)
slot

Sets the maximum map scale (i.e.

most "zoomed in" scale) at which the layer will be visible. The scale value indicates the scale denominator, e.g. 1000.0 for a 1:1000 map. A scale of 0 indicates no maximum scale visibility.

Note
Scale based visibility is only used if setScaleBasedVisibility() is set to true.
See also
maximumScale()
setMinimumScale()
setScaleBasedVisibility()

Definition at line 777 of file qgsmaplayer.cpp.

◆ setMetadata()

void QgsMapLayer::setMetadata ( const QgsLayerMetadata metadata)
virtual

Sets the layer's metadata store.

See also
metadata()
metadataChanged()
Since
QGIS 3.0

Definition at line 2001 of file qgsmaplayer.cpp.

◆ setMetadataUrl()

void QgsMapLayer::setMetadataUrl ( const QString &  metaUrl)
inline

Sets the metadata URL of the layer used by QGIS Server in GetCapabilities request.

MetadataUrl is a a link to the detailed, standardized metadata about the data.

Returns
the layer metadata URL
See also
metadataUrl()

Definition at line 406 of file qgsmaplayer.h.

◆ setMetadataUrlFormat()

void QgsMapLayer::setMetadataUrlFormat ( const QString &  metaUrlFormat)
inline

Sets the metadata format of the layer used by QGIS Server in GetCapabilities request.

MetadataUrlType indicates how the metadata is structured.

Returns
the layer metadata format
See also
metadataUrlFormat()

Definition at line 442 of file qgsmaplayer.h.

◆ setMetadataUrlType()

void QgsMapLayer::setMetadataUrlType ( const QString &  metaUrlType)
inline

Set the metadata type of the layer used by QGIS Server in GetCapabilities request MetadataUrlType indicates the standard to which the metadata complies.

Returns
the layer metadata type
See also
metadataUrlType()

Definition at line 424 of file qgsmaplayer.h.

◆ setMinimumScale

void QgsMapLayer::setMinimumScale ( double  scale)
slot

Sets the minimum map scale (i.e.

most "zoomed out" scale) at which the layer will be visible. The scale value indicates the scale denominator, e.g. 1000.0 for a 1:1000 map. A scale of 0 indicates no minimum scale visibility.

Note
Scale based visibility is only used if setScaleBasedVisibility() is set to true.
See also
minimumScale()
setMaximumScale()
setScaleBasedVisibility()

Definition at line 788 of file qgsmaplayer.cpp.

◆ setName()

void QgsMapLayer::setName ( const QString &  name)

Set the display name of the layer.

See also
name()
Since
QGIS 2.16

Definition at line 164 of file qgsmaplayer.cpp.

◆ setOpacity()

void QgsMapLayer::setOpacity ( double  opacity)
virtual

Sets the opacity for the layer, where opacity is a value between 0 (totally transparent) and 1.0 (fully opaque).

See also
opacity()
opacityChanged()
Note
Prior to QGIS 3.18, this method was available for vector layers only
Since
QGIS 3.18

Reimplemented in QgsRasterLayer.

Definition at line 228 of file qgsmaplayer.cpp.

◆ setOriginalXmlProperties()

void QgsMapLayer::setOriginalXmlProperties ( const QString &  originalXmlProperties)

Sets the original XML properties for the layer to originalXmlProperties.

The storage format for the XML is qlr

Since
QGIS 3.6

Definition at line 2039 of file qgsmaplayer.cpp.

◆ setProviderType()

void QgsMapLayer::setProviderType ( const QString &  providerType)
protected

Sets the providerType (provider key)

Definition at line 2065 of file qgsmaplayer.cpp.

◆ setRefreshOnNofifyMessage

void QgsMapLayer::setRefreshOnNofifyMessage ( const QString &  message)
inlineslot

Set the notification message that triggers repaint If refresh on notification is enabled, the notification will triggerRepaint only if the notification message is equal to.

Parameters
message
Since
QGIS 3.0

Definition at line 1348 of file qgsmaplayer.h.

◆ setRefreshOnNotifyEnabled

void QgsMapLayer::setRefreshOnNotifyEnabled ( bool  enabled)
slot

Set whether provider notification is connected to triggerRepaint.

Since
QGIS 3.0

Definition at line 2090 of file qgsmaplayer.cpp.

◆ setRenderer3D()

void QgsMapLayer::setRenderer3D ( QgsAbstract3DRenderer renderer)

Sets 3D renderer for the layer.

Takes ownership of the renderer.

Since
QGIS 3.0

Definition at line 1970 of file qgsmaplayer.cpp.

◆ setScaleBasedVisibility

void QgsMapLayer::setScaleBasedVisibility ( bool  enabled)
slot

Sets whether scale based visibility is enabled for the layer.

Parameters
enabledset to true to enable scale based visibility
See also
setMinimumScale
setMaximumScale
hasScaleBasedVisibility

Definition at line 793 of file qgsmaplayer.cpp.

◆ setShortName()

void QgsMapLayer::setShortName ( const QString &  shortName)
inline

Sets the short name of the layer used by QGIS Server to identify the layer.

Returns
the layer short name
See also
shortName()

Definition at line 265 of file qgsmaplayer.h.

◆ setSubLayerVisibility()

void QgsMapLayer::setSubLayerVisibility ( const QString &  name,
bool  visible 
)
virtual

Set the visibility of the given sublayer name.

Parameters
namesublayer name
visiblesublayer visibility

Reimplemented in QgsRasterLayer.

Definition at line 814 of file qgsmaplayer.cpp.

◆ setTitle()

void QgsMapLayer::setTitle ( const QString &  title)
inline

Sets the title of the layer used by QGIS Server in GetCapabilities request.

See also
title()

Definition at line 279 of file qgsmaplayer.h.

◆ setTransformContext

virtual void QgsMapLayer::setTransformContext ( const QgsCoordinateTransformContext transformContext)
pure virtualslot

Sets the coordinate transform context to transformContext.

Since
QGIS 3.8

Implemented in QgsVectorTileLayer, QgsPointCloudLayer, and QgsAnnotationLayer.

◆ setValid()

void QgsMapLayer::setValid ( bool  valid)
protected

Sets whether layer is valid or not.

Definition at line 1934 of file qgsmaplayer.cpp.

◆ shortName()

QString QgsMapLayer::shortName ( ) const

Returns the short name of the layer used by QGIS Server to identify the layer.

See also
setShortName()

Definition at line 190 of file qgsmaplayer.cpp.

◆ source()

QString QgsMapLayer::source ( ) const

Returns the source for the layer.

This source may contain usernames, passwords and other sensitive information.

See also
publicSource()

Definition at line 203 of file qgsmaplayer.cpp.

◆ statusChanged

void QgsMapLayer::statusChanged ( const QString &  status)
signal

Emit a signal with status (e.g. to be caught by QgisApp and display a msg on status bar)

◆ styleChanged

void QgsMapLayer::styleChanged ( )
signal

Signal emitted whenever a change affects the layer's style.

Ie this may be triggered by renderer changes, label style changes, or other style changes such as blend mode or layer opacity changes.

Warning
This signal should never be manually emitted. Instead call the emitStyleChanged() method to ensure that the signal is only emitted when appropriate.
See also
rendererChanged()
Since
QGIS 2.16

◆ styleLoaded

void QgsMapLayer::styleLoaded ( QgsMapLayer::StyleCategories  categories)
signal

Emitted when a style has been loaded.

Parameters
categoriesstyle categories
Since
QGIS 3.12

◆ styleManager()

QgsMapLayerStyleManager * QgsMapLayer::styleManager ( ) const

Gets access to the layer's style manager.

Style manager allows switching between multiple styles.

Since
QGIS 2.8

Definition at line 1965 of file qgsmaplayer.cpp.

◆ styleURI()

QString QgsMapLayer::styleURI ( ) const
virtual

Retrieve the style URI for this layer (either as a .qml file on disk or as a record in the users style table in their personal qgis.db)

Returns
a QString with the style file name
See also
also loadNamedStyle() and saveNamedStyle();

Definition at line 934 of file qgsmaplayer.cpp.

◆ subLayers()

QStringList QgsMapLayer::subLayers ( ) const
virtual

Returns the sublayers of this layer.

(Useful for providers that manage their own layers, such as WMS).

Reimplemented in QgsRasterLayer, and QgsMeshLayer.

Definition at line 803 of file qgsmaplayer.cpp.

◆ temporalProperties()

virtual QgsMapLayerTemporalProperties* QgsMapLayer::temporalProperties ( )
inlinevirtual

Returns the layer's temporal properties.

This may be nullptr, depending on the layer type.

Since
QGIS 3.14

Reimplemented in QgsVectorLayer, QgsRasterLayer, and QgsMeshLayer.

Definition at line 1258 of file qgsmaplayer.h.

◆ timestamp()

QDateTime QgsMapLayer::timestamp ( ) const
virtual

Time stamp of data source in the moment when data/metadata were loaded by provider.

Reimplemented in QgsRasterLayer.

Definition at line 2013 of file qgsmaplayer.cpp.

◆ title()

QString QgsMapLayer::title ( ) const
inline

Returns the title of the layer used by QGIS Server in GetCapabilities request.

Returns
the layer title
See also
setTitle()

Definition at line 287 of file qgsmaplayer.h.

◆ transformContext()

QgsCoordinateTransformContext QgsMapLayer::transformContext ( ) const

Returns the layer data provider coordinate transform context or a default transform context if the layer does not have a valid data provider.

Since
QGIS 3.8

Definition at line 840 of file qgsmaplayer.cpp.

◆ trigger3DUpdate

void QgsMapLayer::trigger3DUpdate ( )
slot

Will advise any 3D maps that this layer requires to be updated in the scene.

Will emit a request3DUpdate() signal.

Since
QGIS 3.18

Definition at line 1996 of file qgsmaplayer.cpp.

◆ triggerRepaint

void QgsMapLayer::triggerRepaint ( bool  deferredUpdate = false)
slot

Will advise the map canvas (and any other interested party) that this layer requires to be repainted.

Will emit a repaintRequested() signal. If deferredUpdate is true then the layer will only be repainted when the canvas is next re-rendered, and will not trigger any canvas redraws itself.

Note
in 2.6 function moved from vector/raster subclasses to QgsMapLayer

Definition at line 1986 of file qgsmaplayer.cpp.

◆ type()

QgsMapLayerType QgsMapLayer::type ( ) const

Returns the type of the layer.

Definition at line 140 of file qgsmaplayer.cpp.

◆ undoStack()

QUndoStack * QgsMapLayer::undoStack ( )

Returns pointer to layer's undo stack.

Definition at line 1843 of file qgsmaplayer.cpp.

◆ undoStackStyles()

QUndoStack * QgsMapLayer::undoStackStyles ( )

Returns pointer to layer's style undo stack.

Since
QGIS 2.16

Definition at line 1848 of file qgsmaplayer.cpp.

◆ wgs84Extent()

QgsRectangle QgsMapLayer::wgs84Extent ( bool  forceRecalculate = false) const

Returns the WGS84 extent (EPSG:4326) of the layer according to ReadFlag::FlagTrustLayerMetadata.

If that flag is activated, then the WGS84 extent read in the qgs project is returned. Otherwise, the actual WGS84 extent is returned.

Parameters
forceRecalculateTrue to return the current WGS84 extent whatever the read flags
Since
QGIS 3.20

Definition at line 2128 of file qgsmaplayer.cpp.

◆ willBeDeleted

void QgsMapLayer::willBeDeleted ( )
signal

Emitted in the destructor when the layer is about to be deleted, but it is still in a perfectly valid state: the last chance for other pieces of code for some cleanup if they use the layer.

Since
QGIS 3.0

◆ writeCommonStyle()

void QgsMapLayer::writeCommonStyle ( QDomElement &  layerElement,
QDomDocument &  document,
const QgsReadWriteContext context,
StyleCategories  categories = AllStyleCategories 
) const
protected

Write style data common to all layer types.

Since
QGIS 3.0

Definition at line 583 of file qgsmaplayer.cpp.

◆ writeCustomProperties()

void QgsMapLayer::writeCustomProperties ( QDomNode &  layerNode,
QDomDocument &  doc 
) const
protected

Write custom properties to project file.

Definition at line 689 of file qgsmaplayer.cpp.

◆ writeLayerXml()

bool QgsMapLayer::writeLayerXml ( QDomElement &  layerElement,
QDomDocument &  document,
const QgsReadWriteContext context 
) const

Stores state in DOM node.

Parameters
layerElementis a DOM element corresponding to `‘maplayer’' tag
documentis a the DOM document being written
contextreading context (e.g. for conversion between relative and absolute paths)
Note

The DOM node corresponds to a DOM document project file XML element to be written by QgsProject.

This, in turn, calls writeXml() (and then writeSymbology), which is over-rideable by sub-classes so that they can write their own specific state to the given DOM node.

Invoked by QgsProject::write().

Returns
true if successful

Definition at line 433 of file qgsmaplayer.cpp.

◆ writeStyle()

bool QgsMapLayer::writeStyle ( QDomNode &  node,
QDomDocument &  doc,
QString &  errorMessage,
const QgsReadWriteContext context,
StyleCategories  categories = AllStyleCategories 
) const
virtual

Write just the symbology information for the layer into the document.

Parameters
nodethe node that will have the style element added to it.
docthe document that will have the QDomNode added.
errorMessagereference to string that will be updated with any error messages
contextwriting context (used for transform from absolute to relative paths)
categoriesthe style categories to be written
Returns
true in case of success.
Note
To be implemented in subclasses. Default implementation does nothing and returns false.
There is a confusion of terms with the GUI. This method actually writes what is known as the symbology in the application.
Since
QGIS 2.16

Reimplemented in QgsMeshLayer, and QgsPointCloudLayer.

Definition at line 1673 of file qgsmaplayer.cpp.

◆ writeStyleManager()

void QgsMapLayer::writeStyleManager ( QDomNode &  layerNode,
QDomDocument &  doc 
) const
protected

Write style manager's configuration (if exists). To be called by subclasses.

Definition at line 703 of file qgsmaplayer.cpp.

◆ writeSymbology()

virtual bool QgsMapLayer::writeSymbology ( QDomNode &  node,
QDomDocument &  doc,
QString &  errorMessage,
const QgsReadWriteContext context,
StyleCategories  categories = AllStyleCategories 
) const
pure virtual

Write the style for the layer into the docment provided.

Parameters
nodethe node that will have the style element added to it.
docthe document that will have the QDomNode added.
errorMessagereference to string that will be updated with any error messages
contextwriting context (used for transform from absolute to relative paths)
categoriesthe style categories to be written
Note
There is a confusion of terms with the GUI. This method actually writes what is called a style in the application.
Returns
true in case of success.

Implemented in QgsVectorTileLayer, QgsPointCloudLayer, and QgsAnnotationLayer.

◆ writeXml()

bool QgsMapLayer::writeXml ( QDomNode &  layer_node,
QDomDocument &  document,
const QgsReadWriteContext context 
) const
protectedvirtual

Called by writeLayerXML(), used by children to write state specific to them to project files.

Reimplemented in QgsVectorTileLayer, QgsPointCloudLayer, QgsRasterLayer, QgsMeshLayer, QgsAnnotationLayer, and QgsVectorLayer.

Definition at line 653 of file qgsmaplayer.cpp.

Friends And Related Function Documentation

◆ QgsVectorLayer

friend class QgsVectorLayer
friend

Definition at line 1837 of file qgsmaplayer.h.

Member Data Documentation

◆ mAbstract

QString QgsMapLayer::mAbstract
protected

Description of the layer.

Definition at line 1674 of file qgsmaplayer.h.

◆ mAttribution

QString QgsMapLayer::mAttribution
protected

Attribution of the layer.

Definition at line 1682 of file qgsmaplayer.h.

◆ mAttributionUrl

QString QgsMapLayer::mAttributionUrl
protected

Definition at line 1683 of file qgsmaplayer.h.

◆ mBlockStyleChangedSignal

int QgsMapLayer::mBlockStyleChangedSignal = 0
protected

If non-zero, the styleChanged signal should not be emitted.

Since
QGIS 3.20

Definition at line 1737 of file qgsmaplayer.h.

◆ mDataSource

QString QgsMapLayer::mDataSource
protected

Data source description string, varies by layer type.

Definition at line 1665 of file qgsmaplayer.h.

◆ mDataUrl

QString QgsMapLayer::mDataUrl
protected

DataUrl of the layer.

Definition at line 1678 of file qgsmaplayer.h.

◆ mDataUrlFormat

QString QgsMapLayer::mDataUrlFormat
protected

Definition at line 1679 of file qgsmaplayer.h.

◆ mDependencies

QSet<QgsMapLayerDependency> QgsMapLayer::mDependencies
protected

List of layers that may modify this layer on modification.

Definition at line 1698 of file qgsmaplayer.h.

◆ mError

QgsError QgsMapLayer::mError
protected

Error.

Definition at line 1695 of file qgsmaplayer.h.

◆ mIsRefreshOnNofifyEnabled

bool QgsMapLayer::mIsRefreshOnNofifyEnabled = false
protected

Definition at line 1707 of file qgsmaplayer.h.

◆ mKeywordList

QString QgsMapLayer::mKeywordList
protected

Definition at line 1675 of file qgsmaplayer.h.

◆ mLayerName

QString QgsMapLayer::mLayerName
protected

Name of the layer - used for display.

Definition at line 1668 of file qgsmaplayer.h.

◆ mLayerOpacity

double QgsMapLayer::mLayerOpacity = 1.0
protected

Layer opacity.

Since
QGIS 3.18

Definition at line 1730 of file qgsmaplayer.h.

◆ mLegendUrl

QString QgsMapLayer::mLegendUrl
protected

WMS legend.

Definition at line 1691 of file qgsmaplayer.h.

◆ mLegendUrlFormat

QString QgsMapLayer::mLegendUrlFormat
protected

Definition at line 1692 of file qgsmaplayer.h.

◆ mMetadataUrl

QString QgsMapLayer::mMetadataUrl
protected

MetadataUrl of the layer.

Definition at line 1686 of file qgsmaplayer.h.

◆ mMetadataUrlFormat

QString QgsMapLayer::mMetadataUrlFormat
protected

Definition at line 1688 of file qgsmaplayer.h.

◆ mMetadataUrlType

QString QgsMapLayer::mMetadataUrlType
protected

Definition at line 1687 of file qgsmaplayer.h.

◆ mProviderKey

QString QgsMapLayer::mProviderKey
protected

Data provider key (name of the data provider)

Definition at line 1711 of file qgsmaplayer.h.

◆ mReadFlags

QgsMapLayer::ReadFlags QgsMapLayer::mReadFlags = QgsMapLayer::ReadFlags()
protected

Read flags. It's up to the subclass to respect these when restoring state from XML.

Definition at line 1716 of file qgsmaplayer.h.

◆ mRefreshOnNofifyMessage

QString QgsMapLayer::mRefreshOnNofifyMessage
protected

Definition at line 1708 of file qgsmaplayer.h.

◆ mShortName

QString QgsMapLayer::mShortName
protected

Definition at line 1670 of file qgsmaplayer.h.

◆ mShouldValidateCrs

bool QgsMapLayer::mShouldValidateCrs = true
protected

true if the layer's CRS should be validated and invalid CRSes are not permitted.

Since
QGIS 3.10

Definition at line 1723 of file qgsmaplayer.h.

◆ mTitle

QString QgsMapLayer::mTitle
protected

Definition at line 1671 of file qgsmaplayer.h.

◆ mValid

bool QgsMapLayer::mValid = false
protected

Indicates if the layer is valid and can be drawn.

Definition at line 1662 of file qgsmaplayer.h.

Property Documentation

◆ autoRefreshInterval

int QgsMapLayer::autoRefreshInterval
readwrite

Definition at line 1860 of file qgsmaplayer.h.

◆ crs

QgsCoordinateReferenceSystem QgsMapLayer::crs
readwrite

Definition at line 1860 of file qgsmaplayer.h.

◆ isValid

bool QgsMapLayer::isValid
read

Definition at line 1860 of file qgsmaplayer.h.

◆ metadata

QgsLayerMetadata QgsMapLayer::metadata
readwrite

Definition at line 1860 of file qgsmaplayer.h.

◆ name

QString QgsMapLayer::name
readwrite

Definition at line 1860 of file qgsmaplayer.h.

◆ opacity

double QgsMapLayer::opacity
readwrite

Definition at line 1860 of file qgsmaplayer.h.

◆ type

QgsMapLayerType QgsMapLayer::type
read

Definition at line 1860 of file qgsmaplayer.h.


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