Class: QgsMapLayer

Base class for all map layer types.

This is the base class for all map layer types (vector, raster, mesh, point cloud, annotations, etc).

Note

This is an abstract class, with methods which must be implemented by a subclass.

The following methods must be implemented: clone(), createMapRenderer(), readSymbology(), setTransformContext(), writeSymbology()

Class Hierarchy

Base classes

QObject

Subclasses

QgsAnnotationLayer	Represents a map layer containing a set of georeferenced annotations, e.g. markers, lines, polygons or text items.
QgsVectorLayer	Represents a vector layer which manages a vector based dataset.
QgsGroupLayer	A map layer which consists of a set of child layers, where all component layers are rendered as a single flattened object during map renders.
QgsMeshLayer	Represents a mesh layer supporting display of data on structured or unstructured meshes.
QgsPluginLayer	Base class for plugin layers.
QgsPointCloudLayer	Represents a map layer supporting display of point clouds.
QgsRasterLayer	Represents a raster layer.
QgsTiledSceneLayer	Represents a map layer supporting display of tiled scene objects.
QgsVectorTileLayer	Implements a map layer that is dedicated to rendering of vector tiles.

Enums

LayerType	Types of layers that can be added to a map
SaveStyleResult	Results of saving styles to database.

Abstract Methods

clone	Returns a new instance equivalent to this one except for the id which is still unique.
createMapRenderer	Returns new instance of QgsMapLayerRenderer that will be used for rendering of given context
readSymbology	Read the symbology for the current layer from the DOM node supplied.
setTransformContext	Sets the coordinate transform context to transformContext
writeSymbology	Write the style for the layer into the document provided.

Methods

abstract	Returns the abstract of the layer used by QGIS Server in GetCapabilities request.
appendError	Add error message
attribution	Returns the attribution of the layer used by QGIS Server in GetCapabilities request.
attributionUrl	Returns the attribution URL of the layer used by QGIS Server in GetCapabilities request.
autoRefreshInterval	Returns the auto refresh interval (in milliseconds).
autoRefreshMode	Returns the layer's automatic refresh mode.
blendMode	Returns the current blending mode for a layer.
crs	Returns the layer's spatial reference system.
crs3D	Returns the CRS to use for the layer when transforming 3D data, or when z/elevation value handling is important.
customProperties	Read all custom properties from layer.
customProperty	Read a custom property from layer.
customPropertyKeys	Returns list of all keys within custom properties.
dataUrl	Returns the DataUrl of the layer used by QGIS Server in GetCapabilities request.
dataUrlFormat	Returns the DataUrl format of the layer used by QGIS Server in GetCapabilities request.
emitStyleChanged	Triggers an emission of the styleChanged() signal.
exportNamedMetadata	Export the current metadata of this layer as named metadata in a QDomDocument
flags	Returns the flags for this layer.
hasAutoRefreshEnabled	Returns True if auto refresh is enabled for the layer.
hasDependencyCycle	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.
hasScaleBasedVisibility	Returns whether scale based visibility is enabled for the layer.
id	Returns the layer's unique ID, which is used to access this layer from QgsProject.
importNamedMetadata	Import the metadata of this layer from a QDomDocument
invalidateWgs84Extent	Invalidates the WGS84 extent.
isInScaleRange	Tests whether the layer should be visible at the specified scale.
isRefreshOnNotifyEnabled	Returns True if the refresh on provider nofification is enabled
isValid	Returns the status of the layer.
keywordList	Returns the keyword list of the layer used by QGIS Server in GetCapabilities request.
legend	Can be None.
legendPlaceholderImage	Returns path to the placeholder image or an empty string if a generated legend is shown
legendUrl	Returns the URL for the layer's legend.
legendUrlFormat	Returns the format for a URL based layer legend.
loadNamedMetadataFromDatabase	Retrieve a named metadata for this layer from a sqlite database.
mapTipTemplate	The mapTip is a pretty, html representation for feature information.
mapTipsEnabled	Returns true if map tips are enabled for this layer
maximumScale	Returns the maximum map scale (i.e. most "zoomed in" scale) at which the layer will be visible.
metadata	Returns a reference to the layer's metadata store.
metadataUrl	Returns the metadata URL of the layer used by QGIS Server in GetCapabilities request.
metadataUrlFormat	Returns the metadata format of the layer used by QGIS Server in GetCapabilities request.
metadataUrlType	Returns the metadata type of the layer used by QGIS Server in GetCapabilities request.
minimumScale	Returns the minimum map scale (i.e. most "zoomed out" scale) at which the layer will be visible.
name	Returns the display name of the layer.
originalXmlProperties	Returns the XML properties of the original layer as they were when the layer was first read from the project file.
project	Returns the parent project if this map layer is added to a project.
providerMetadata	Returns the layer data provider's metadata, it may be None.
providerType	Returns the provider type (provider key) for this layer
publicSource	Gets a version of the internal layer definition that has sensitive bits removed (for example, the password).
readCommonStyle	Read style data common to all layer types
readCustomProperties	Read custom properties from project file.
readLayerXml	Sets state from DOM document
readOnly	Returns if this layer is read only.
readStyleManager	Read style manager's configuration (if any).
refreshOnNotifyMessage	Returns the message that should be notified by the provider to triggerRepaint
removeCustomProperty	Remove a custom property from layer.
renderer3D	Returns 3D renderer associated with the layer.
saveNamedMetadata	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)
saveStyleToDatabaseV2	Saves QML and SLD representations of the layer's style to a table in the database.
serverProperties	Returns QGIS Server Properties for the map layer
setAbstract	Sets the abstract of the layer used by QGIS Server in GetCapabilities request.
setAttribution	Sets the attribution of the layerused by QGIS Server in GetCapabilities request.
setAttributionUrl	Sets the attribution URL of the layer used by QGIS Server in GetCapabilities request.
setAutoRefreshEnabled	Sets whether auto refresh is enabled for the layer.
setAutoRefreshInterval	Sets the auto refresh interval (in milliseconds) for the layer.
setAutoRefreshMode	Sets the automatic refresh mode for the layer.
setBlendMode	Set the blending mode used for rendering a layer.
setCrs	Sets layer's spatial reference system.
setCustomProperties	Set custom properties for layer.
setCustomProperty	Set a custom property for layer.
setDataSource	Updates the data source of the layer.
setDataUrl	Sets the DataUrl of the layer used by QGIS Server in GetCapabilities request.
setDataUrlFormat	Sets the DataUrl format of the layer used by QGIS Server in GetCapabilities request.
setError	Sets error message
setFlags	Returns the flags for this layer.
setId	Sets the layer's id.
setKeywordList	Sets the keyword list of the layerused by QGIS Server in GetCapabilities request.
setLegend	Assign a legend controller to the map layer.
setLegendPlaceholderImage	Set placeholder image for legend.
setLegendUrl	Sets the URL for the layer's legend.
setLegendUrlFormat	Sets the format for a URL based layer legend.
setMapTipTemplate	The mapTip is a pretty, html representation for feature information.
setMapTipsEnabled	Enable or disable map tips for this layer
setMaximumScale	Sets the maximum map scale (i.e. most "zoomed in" scale) at which the layer will be visible.
setMetadataUrl	Sets the metadata URL of the layer used by QGIS Server in GetCapabilities request.
setMetadataUrlFormat	Sets the metadata format of the layer used by QGIS Server in GetCapabilities request.
setMetadataUrlType	Set the metadata type of the layer used by QGIS Server in GetCapabilities request MetadataUrlType indicates the standard to which the metadata complies.
setMinimumScale	Sets the minimum map scale (i.e. most "zoomed out" scale) at which the layer will be visible.
setName	Set the display name of the layer.
setOriginalXmlProperties	Sets the original XML properties for the layer to originalXmlProperties
setProviderType	Sets the providerType (provider key)
setRefreshOnNofifyMessage	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:param message:
setRefreshOnNotifyEnabled	Set whether provider notification is connected to triggerRepaint
setRenderer3D	Sets 3D renderer for the layer.
setScaleBasedVisibility	Sets whether scale based visibility is enabled for the layer.
setShortName	Sets the short name of the layer used by QGIS Server to identify the layer.
setTitle	Sets the title of the layer used by QGIS Server in GetCapabilities request.
setValid	Sets whether layer is valid or not
setVerticalCrs	Sets the layer's vertical coordinate reference system.
shortName	Returns the short name of the layer used by QGIS Server to identify the layer.
source	Returns the source for the layer.
styleManager	Gets access to the layer's style manager.
title	Returns the title of the layer used by QGIS Server in GetCapabilities request.
transformContext	Returns the layer data provider coordinate transform context or a default transform context if the layer does not have a valid data provider.
trigger3DUpdate	Will advise any 3D maps that this layer requires to be updated in the scene.
triggerRepaint	Will advise the map canvas (and any other interested party) that this layer requires to be repainted.
type	Returns the type of the layer.
undoStack	Returns pointer to layer's undo stack
undoStackStyles	Returns pointer to layer's style undo stack
verticalCrs	Returns the layer's vertical coordinate reference system.
wgs84Extent	Returns the WGS84 extent (EPSG:4326) of the layer according to ReadFlag.FlagTrustLayerMetadata.
writeCommonStyle	Write style data common to all layer types
writeCustomProperties	Write custom properties to project file.
writeLayerXml	Stores state in DOM node
writeStyleManager	Write style manager's configuration (if exists).

Virtual Methods

In PyQGIS, only methods marked as virtual can be safely overridden in a Python subclass of QgsMapLayer. See the FAQ for more details.

accept	Accepts the specified symbology visitor, causing it to visit all symbols associated with the layer.
dataProvider	Returns the layer's data provider, it may be None.
decodedSource	Called by readLayerXML(), used by derived classes to decode provider's specific data source from project files.
deleteStyleFromDatabase	Deletes a style from the database
dependencies	Gets the list of dependencies.
elevationProperties	Returns the layer's elevation properties.
encodedSource	Called by writeLayerXML(), used by derived classes to encode provider's specific data source to project files.
error	Gets current status error.
exportNamedStyle	Export the properties of this layer as named style in a QDomDocument
exportSldStyle	Export the properties of this layer as SLD style in a QDomDocument
exportSldStyleV2	Export the properties of this layer as SLD style in a QDomDocument
exportSldStyleV3	Export the properties of this layer as SLD style in a QDomDocument.
extent	Returns the extent of the layer.
extent3D	Returns the 3D extent of the layer.
getStyleFromDatabase	Returns the named style corresponding to style id provided
hasMapTips	Returns True if the layer contains map tips.
htmlMetadata	Obtain a formatted HTML string containing assorted metadata for this layer.
importNamedStyle	Import the properties of this layer from a QDomDocument
isEditable	Returns True if the layer can be edited.
isModified	Returns True if the layer has been modified since last commit/save.
isSpatial	Returns True if the layer is considered a spatial layer, ie it has some form of geometry associated with it.
isTemporary	Returns True if the layer is considered a temporary layer.
listStylesInDatabase	Lists all the style in db split into related to the layer and not related to
loadDefaultMetadata	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)
loadDefaultStyle	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)
loadNamedMetadata	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)
loadNamedStyle	Loads a named style from file/local db/datasource db
loadNamedStyleFromDatabase	Retrieve a named style for this layer from a sqlite database.
loadSldStyle	Attempts to style the layer using the formatting from an SLD type file.
metadataUri	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)
opacity	Returns the opacity for the layer, where opacity is a value between 0 (totally transparent) and 1.0 (fully opaque).
profileSource	Returns the layer's profile source if it has profile capabilities.
properties	Returns the map layer properties of this layer.
readSld
readStyle	Read the style for the current layer from the DOM node supplied.
readXml	Called by readLayerXML(), used by children to read state specific to them from project files.
reload	Synchronises with changes in the datasource
resolveReferences	Resolve references to other layers (kept as layer IDs after reading XML) into layer objects.
saveDefaultMetadata	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)
saveDefaultStyle	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)
saveNamedStyle	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)
saveSldStyle	Saves the properties of this layer to an SLD format file.
saveSldStyleV2	Saves the properties of this layer to an SLD format file.
saveStyleToDatabase	Saves QML and SLD representations of the layer's style to a table in the database.
selectionProperties	Returns the layer's selection properties.
setDependencies	Sets the list of dependencies.
setExtent	Sets the extent
setExtent3D	Sets the extent
setLayerOrder	Reorders the previously selected sublayers of this layer from bottom to top.
setMetadata	Sets the layer's metadata store.
setOpacity	Sets the opacity for the layer, where opacity is a value between 0 (totally transparent) and 1.0 (fully opaque).
setSubLayerVisibility	Set the visibility of the given sublayer name.
styleURI	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)
subLayers	Returns the sublayers of this layer.
supportsEditing	Returns whether the layer supports editing or not.
temporalProperties	Returns the layer's temporal properties.
timestamp	Time stamp of data source in the moment when data/metadata were loaded by provider
writeStyle	Write just the symbology information for the layer into the document
writeXml	Called by writeLayerXML(), used by children to write state specific to them to project files.

Static Methods

extensionPropertyType	Returns the extension of a Property.
formatLayerName	A convenience function to capitalize and format a layer name.
generateId	Generates an unique identifier for this layer, the generate ID is prefixed by layerName
providerReadFlags	Returns provider read flag deduced from layer read flags layerReadFlags and a dom node layerNode that describes a layer (corresponding to maplayer tag in a DOM document project file read by QgsProject).

Signals

autoRefreshIntervalChanged	Emitted when the auto refresh interval changes.
beforeResolveReferences	Emitted when all layers are loaded and references can be resolved, just before the references of this layer are resolved.
blendModeChanged	Signal emitted when the blend mode is changed, through QgsMapLayer.setBlendMode()
configChanged	Emitted whenever the configuration is changed.
crs3DChanged	Emitted when the crs3D() of the layer has changed.
crsChanged	Emitted when the crs() of the layer has changed.
customPropertyChanged	Emitted when a custom property of the layer has been changed or removed.
dataChanged	Data of layer changed
dataSourceChanged	Emitted whenever the layer's data source has been changed.
dependenciesChanged	Emitted when dependencies are changed.
editingStarted	Emitted when editing on this layer has started.
editingStopped	Emitted when edited changes have been successfully written to the data provider.
flagsChanged	Emitted when layer's flags have been modified.
idChanged	Emitted when the layer's ID has been changed.
isValidChanged	Emitted when the validity of this layer changed.
layerModified	Emitted when modifications has been done on layer
legendChanged	Signal emitted when legend of the layer has changed
mapTipTemplateChanged	Emitted when the map tip template changes
mapTipsEnabledChanged	Emitted when map tips are enabled or disabled for the layer.
metadataChanged	Emitted when the layer's metadata is changed.
nameChanged	Emitted when the name has been changed
opacityChanged	Emitted when the layer's opacity is changed, where opacity is a value between 0 (transparent) and 1 (opaque).
recalculateExtents	This is used to send a request that any mapcanvas using this layer update its extents
renderer3DChanged	Signal emitted when 3D renderer associated with the layer has changed.
rendererChanged	Signal emitted when renderer is changed.
repaintRequested	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.
request3DUpdate	Signal emitted when a layer requires an update in any 3D maps.
statusChanged	Emit a signal with status (e.g. to be caught by QgisApp and display a msg on status bar).
styleChanged	Signal emitted whenever a change affects the layer's style.
styleLoaded	Emitted when a style has been loaded
verticalCrsChanged	Emitted when the verticalCrs() of the layer has changed.
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.

Attributes

Actions
AllAttributeCategories
AllStyleCategories
AllVisualStyleCategories
AttributeTable
CustomProperties
Diagrams
Elevation
Fields
FlagDontResolveLayers
FlagForceReadOnly
FlagReadExtentFromXml
FlagTrustLayerMetadata
Forms
GeometryOptions
Identifiable
Labeling
LayerConfiguration
Legend
MapTips
Metadata
Notes
Private
Relations
Removable
Rendering
Searchable
Style
Symbology
Symbology3D
Temporal

class qgis.core.QgsMapLayer

Bases: QObject

__init__(type: Qgis.LayerType = Qgis.LayerType.Vector, name: str | None = '', source: str | None = '')

Constructor for QgsMapLayer

Parameters:

• type (Qgis.LayerType = Qgis.LayerType.Vector) – layer type

• name (Optional[str] = '') – display name for the layer

• source (Optional[str] = '') – datasource of layer

Actions = 64

AllAttributeCategories = 560

AllStyleCategories = 262143

AllVisualStyleCategories = 270

AttributeTable = 512

CustomProperties = 2048

Diagrams = 256

Elevation = 65536

Fields = 16

FlagDontResolveLayers = 1

FlagForceReadOnly = 8

FlagReadExtentFromXml = 4

FlagTrustLayerMetadata = 2

Forms = 32

GeometryOptions = 4096

Identifiable = 1

Labeling = 8

LayerConfiguration = 1

class LayerFlag

Bases: int

class LayerFlags

class LayerFlags(f: QgsMapLayer.LayerFlags | QgsMapLayer.LayerFlag)

class LayerFlags(a0: QgsMapLayer.LayerFlags)

Bases: object

class LayerType(*values)

Bases: IntEnum

Types of layers that can be added to a map

Added in version 3.30..

• Vector: Vector layer

  Available as QgsMapLayer.VectorLayer in older QGIS releases.

• Raster: Raster layer

  Available as QgsMapLayer.RasterLayer in older QGIS releases.

• Plugin: Plugin based layer

  Available as QgsMapLayer.PluginLayer in older QGIS releases.

• Mesh: Mesh layer. Added in QGIS 3.2

  Available as QgsMapLayer.MeshLayer in older QGIS releases.

• VectorTile: Vector tile layer. Added in QGIS 3.14

  Available as QgsMapLayer.VectorTileLayer in older QGIS releases.

• Annotation: Contains freeform, georeferenced annotations. Added in QGIS 3.16

  Available as QgsMapLayer.AnnotationLayer in older QGIS releases.

• PointCloud: Point cloud layer. Added in QGIS 3.18

  Available as QgsMapLayer.PointCloudLayer in older QGIS releases.

• Group: Composite group layer. Added in QGIS 3.24

  Available as QgsMapLayer.GroupLayer in older QGIS releases.

• TiledScene: Tiled scene layer. Added in QGIS 3.34

Legend = 32768

MapTips = 128

Metadata = 1

Notes = 131072

Private = 8

class PropertyType

Bases: int

class ReadFlag

Bases: int

class ReadFlags

class ReadFlags(f: QgsMapLayer.ReadFlags | QgsMapLayer.ReadFlag)

class ReadFlags(a0: QgsMapLayer.ReadFlags)

Bases: object

Relations = 8192

Removable = 2

Rendering = 1024

class SaveStyleResult(*values)

Bases: IntEnum

Results of saving styles to database.

Added in version 4.0.

• Success: Both QML and SLD formats were successfully written to the database.

• QmlGenerationFailed: Generation of the QML failed, and was not written to the database.

• SldGenerationFailed: Generation of the SLD failed, and was not written to the database.

• DatabaseWriteFailed: An error occurred when attempting to write to the database.

DatabaseWriteFailed = 4

QmlGenerationFailed = 1

SldGenerationFailed = 2

Success = 0

class SaveStyleResults

class SaveStyleResults(f: QgsMapLayer.SaveStyleResults | QgsMapLayer.SaveStyleResult)

class SaveStyleResults(a0: QgsMapLayer.SaveStyleResults)

Bases: object

Searchable = 4

Style = 0

class StyleCategories

class StyleCategories(f: QgsMapLayer.StyleCategories | QgsMapLayer.StyleCategory)

class StyleCategories(a0: QgsMapLayer.StyleCategories)

Bases: object

class StyleCategory

Bases: int

Symbology = 2

Symbology3D = 4

Temporal = 16384

abstract(self) → str

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

Deprecated since version 3.38: Use serverProperties()->:py:func:~QgsMapLayer.abstract instead.

Return type:

str

virtual accept(self, visitor: QgsStyleEntityVisitorInterface | None) → bool

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.

Added in version 3.10.

Parameters:

visitor (Optional[QgsStyleEntityVisitorInterface])

Return type:

bool

appendError(self, error: QgsErrorMessage)

Add error message

Parameters:

error (QgsErrorMessage)

attribution(self) → str

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

Deprecated since version 3.38: Use serverProperties()->:py:func:~QgsMapLayer.attribution instead.

Return type:

str

attributionUrl(self) → str

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

Deprecated since version 3.38: Use serverProperties()->:py:func:~QgsMapLayer.attributionUrl instead.

Return type:

str

autoRefreshInterval(self) → int

Returns the auto refresh interval (in milliseconds). Note that auto refresh is only active when hasAutoRefreshEnabled() is True.

See also

hasAutoRefreshEnabled()

See also

setAutoRefreshInterval()

Return type:

int

signal autoRefreshIntervalChanged(interval: int)

Emitted when the auto refresh interval changes.

See also

setAutoRefreshInterval()

Parameters:

interval (int)

autoRefreshMode(self) → Qgis.AutoRefreshMode

Returns the layer’s automatic refresh mode.

See also

autoRefreshInterval()

See also

setAutoRefreshMode()

Added in version 3.34.

Return type:

Qgis.AutoRefreshMode

signal beforeResolveReferences(project: QgsProject)

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

Added in version 3.10.

Parameters:

project (QgsProject)

blendMode(self) → QPainter.CompositionMode

Returns the current blending mode for a layer.

See also

setBlendMode()

Return type:

QPainter.CompositionMode

signal blendModeChanged(blendMode: QPainter.CompositionMode)

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

Parameters:

blendMode (QPainter.CompositionMode)

abstract clone(self) → QgsMapLayer | None

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

Return type:

Optional[QgsMapLayer]

Returns:

a new layer instance

abstract clone(self, layer: QgsMapLayer | None)

Copies attributes like name, short name, … into another layer.

Parameters:

layer (Optional[QgsMapLayer]) – The copy recipient

signal configChanged

Emitted whenever the configuration is changed. The project listens to this signal to be marked as dirty.

abstract createMapRenderer(self, rendererContext: QgsRenderContext) → QgsMapLayerRenderer | None

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

Parameters:

rendererContext (QgsRenderContext)

Return type:

Optional[QgsMapLayerRenderer]

crs(self) → QgsCoordinateReferenceSystem

Returns the layer’s spatial reference system.

Warning

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

See also

setCrs()

See also

crs3D()

See also

verticalCrs()

See also

crsChanged()

Return type:

QgsCoordinateReferenceSystem

crs3D(self) → QgsCoordinateReferenceSystem

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

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

Warning

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

See also

crs()

See also

verticalCrs()

See also

crs3DChanged()

Added in version 3.38.

Return type:

QgsCoordinateReferenceSystem

signal crs3DChanged

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

See also

crs3D()

See also

crsChanged()

See also

verticalCrsChanged()

Added in version 3.38.

signal crsChanged

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

See also

crs()

See also

setCrs()

See also

verticalCrsChanged()

See also

crs3DChanged()

customProperties(self) → QgsObjectCustomProperties

Read all custom properties from layer. Properties are stored in a map and saved in project file.

See also

setCustomProperties()

Added in version 3.14.

Return type:

QgsObjectCustomProperties

customProperty(self, value: str | None, defaultValue: Any = None) → Any

Read a custom property from layer. Properties are stored in a map and saved in project file.

See also

setCustomProperty()

Parameters:

• value (Optional[str])

• defaultValue (Any = None)

Return type:

Any

signal customPropertyChanged(key: str)

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

Added in version 3.18.

Parameters:

key (str)

customPropertyKeys(self) → List[str]

Returns list of all keys within custom properties. Properties are stored in a map and saved in project file.

See also

customProperty()

Return type:

List[str]

signal dataChanged

Data of layer changed

virtual dataProvider(self) → QgsDataProvider | None

Returns the layer’s data provider, it may be None.

Return type:

Optional[QgsDataProvider]

signal dataSourceChanged

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

See also

setDataSource()

Added in version 3.5.

dataUrl(self) → str

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

Deprecated since version 3.38: Use serverProperties()->:py:func:~QgsMapLayer.dataUrl instead.

Return type:

str

dataUrlFormat(self) → str

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

Deprecated since version 3.38: Use serverProperties()->:py:func:~QgsMapLayer.dataUrlFormat instead.

Return type:

str

virtual decodedSource(self, source: str | None, dataProvider: str | None, context: QgsReadWriteContext) → str

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:

• source (Optional[str]) – data source to decode, typically read from layer’s DOM element “datasource”

• dataProvider (Optional[str]) – string identification of data provider (e.g. “ogr”), typically read from layer’s DOM element

• context (QgsReadWriteContext) – reading context (e.g. for conversion between relative and absolute paths)

Return type:

str

Returns:

decoded source, typically to be used as the layer’s datasource

Added in version 3.2.

virtual deleteStyleFromDatabase(self, styleId: str | None)

Deletes a style from the database

Parameters:

styleId (Optional[str]) -> (bool) – the provider’s layer_styles table id of the style to delete

Returns:

• True in case of success

• msgError: a descriptive error message if any occurs

virtual dependencies(self) → Set[QgsMapLayerDependency]

Gets the list of dependencies. This includes data dependencies set by the user (setDataDependencies()) as well as dependencies given by the provider

Return type:

Set[QgsMapLayerDependency]

Returns:

a set of QgsMapLayerDependency

signal dependenciesChanged

Emitted when dependencies are changed.

signal editingStarted

Emitted when editing on this layer has started.

Added in version 3.22.

signal editingStopped

Emitted when edited changes have been successfully written to the data provider.

Added in version 3.22.

virtual elevationProperties(self) → QgsMapLayerElevationProperties | None

Returns the layer’s elevation properties. This may be None, depending on the layer type.

Added in version 3.18.

Return type:

Optional[QgsMapLayerElevationProperties]

emitStyleChanged(self)

Triggers an emission of the styleChanged() signal.

virtual encodedSource(self, source: str | None, context: QgsReadWriteContext) → str

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:

• source (Optional[str]) – data source to encode, typically QgsMapLayer.source()

• context (QgsReadWriteContext) – writing context (e.g. for conversion between relative and absolute paths)

Return type:

str

Returns:

encoded source, typically to be written in the DOM element “datasource”

Added in version 3.2.

virtual error(self) → QgsError

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.

Return type:

QgsError

exportNamedMetadata(self, doc: QDomDocument, errorMsg: str | None)

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

Parameters:

• doc (QDomDocument) – the target QDomDocument

• errorMsg (Optional[str]) – will be set to a descriptive message if an error occurs

virtual exportNamedStyle(self, doc: QDomDocument, context: QgsReadWriteContext = QgsReadWriteContext(), categories: QgsMapLayer.StyleCategories | QgsMapLayer.StyleCategory = QgsMapLayer.AllStyleCategories) → str

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

Parameters:

• doc (QDomDocument) – the target QDomDocument

• context (QgsReadWriteContext = QgsReadWriteContext()) – read write context

• categories (Union[QgsMapLayer.StyleCategories, QgsMapLayer.StyleCategory] = QgsMapLayer.AllStyleCategories) – the style categories to export during the execution of writeSymbology

Return type:

str

Returns:

a descriptive message if an error occurs

virtual exportSldStyle(self, doc: QDomDocument, errorMsg: str | None)

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

Parameters:

• doc (QDomDocument) – the target QDomDocument

• errorMsg (Optional[str]) – will be set to a descriptive message if an error occurs during the execution of writeSymbology

Deprecated since version 3.44: Use exportSldStyleV3() instead.

virtual exportSldStyleV2(self, doc: QDomDocument, errorMsg: str | None, exportContext: QgsSldExportContext)

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

Parameters:

• doc (QDomDocument) – the target QDomDocument

• errorMsg (Optional[str]) – will be set to a descriptive message if an error occurs during the execution of writeSymbology()

• exportContext (QgsSldExportContext) – SLD export context

Deprecated since version 3.44: Use exportSldStyleV3() instead.

virtual exportSldStyleV3(self, exportContext: QgsSldExportContext) → QDomDocument

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

Errors and warnings raised during the conversion should be retrieved from exportContext.

Parameters:

exportContext (QgsSldExportContext) – SLD export context

Added in version 3.44.

Return type:

QDomDocument

static extensionPropertyType(type: QgsMapLayer.PropertyType) → str

Returns the extension of a Property.

Return type:

str

Returns:

The extension

Parameters:

type (QgsMapLayer.PropertyType)

virtual extent(self) → QgsRectangle

Returns the extent of the layer.

Return type:

QgsRectangle

virtual extent3D(self) → QgsBox3D

Returns the 3D extent of the layer.

Added in version 3.36.

Return type:

QgsBox3D

flags(self) → QgsMapLayer.LayerFlags

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.

See also

properties()

Added in version 3.4.

Return type:

QgsMapLayer.LayerFlags

signal flagsChanged

Emitted when layer’s flags have been modified.

See also

setFlags()

See also

flags()

Added in version 3.4.

static formatLayerName(name: str | None) → str

A convenience function to capitalize and format a layer name.

Parameters:

name (Optional[str])

Return type:

str

static generateId(layerName: str | None) → str

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

Added in version 3.8.

Parameters:

layerName (Optional[str])

Return type:

str

virtual getStyleFromDatabase(self, styleId: str | None)

Returns the named style corresponding to style id provided

Parameters:

styleId (Optional[str]) -> (str)

hasAutoRefreshEnabled(self) → bool

Returns True if auto refresh is enabled for the layer.

See also

autoRefreshInterval()

See also

setAutoRefreshEnabled()

Deprecated since version 3.40: Use autoRefreshMode() instead.

Return type:

bool

hasDependencyCycle(self, a0: Iterable[QgsMapLayerDependency]) → bool

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 version 3.10.

Parameters:

a0 (Iterable[QgsMapLayerDependency])

Return type:

bool

virtual hasMapTips(self) → bool

Returns True if the layer contains map tips.

See also

mapTipTemplate()

See also

setMapTipTemplate()

Return type:

bool

hasScaleBasedVisibility(self) → bool

Returns whether scale based visibility is enabled for the layer.

Return type:

bool

Returns:

True if scale based visibility is enabled

See also

minimumScale()

See also

maximumScale()

See also

setScaleBasedVisibility()

See also

isInScaleRange()

virtual htmlMetadata(self) → str

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

Return type:

str

id(self) → str

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

See also

setId()

See also

idChanged()

Return type:

str

signal idChanged(id: str)

Emitted when the layer’s ID has been changed.

See also

id()

See also

setId()

Added in version 3.38.

Parameters:

id (str)

importNamedMetadata(self, document: QDomDocument, errorMessage: str | None) → bool

Import the metadata of this layer from a QDomDocument

Parameters:

• document (QDomDocument) – source QDomDocument

• errorMessage (Optional[str]) – will be set to a descriptive message if an error occurs

Return type:

bool

Returns:

True on success

virtual importNamedStyle(self, doc: QDomDocument, categories: QgsMapLayer.StyleCategories | QgsMapLayer.StyleCategory = QgsMapLayer.AllStyleCategories)

Import the properties of this layer from a QDomDocument

Parameters:

• doc (QDomDocument) – source QDomDocument

• categories (Union[QgsMapLayer.StyleCategories, QgsMapLayer.StyleCategory] = QgsMapLayer.AllStyleCategories) -> (bool) – the style categories to import

Returns:

• True on success

• errorMsg: a descriptive message if an error occurs during the execution of readSymbology()

invalidateWgs84Extent(self)

Invalidates the WGS84 extent. If FlagTrustLayerMetadata is enabled, the extent is not invalidated because we want to trust metadata whatever happens.

Added in version 3.20.

virtual isEditable(self) → bool

Returns True if the layer can be edited.

Return type:

bool

isInScaleRange(self, scale: float) → bool

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.

Return type:

bool

Returns:

True if the layer is visible at the given scale.

See also

minimumScale()

See also

maximumScale()

See also

hasScaleBasedVisibility()

Parameters:

scale (float)

virtual isModified(self) → bool

Returns True if the layer has been modified since last commit/save.

Note

default implementation returns False.

Added in version 3.22.

Return type:

bool

isRefreshOnNotifyEnabled(self) → bool

Returns True if the refresh on provider nofification is enabled

Return type:

bool

virtual isSpatial(self) → bool

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

Return type:

bool

virtual isTemporary(self) → bool

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)

Added in version 3.10.1.

Return type:

bool

isValid(self) → bool

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.

Return type:

bool

Returns:

True if the layer is valid and can be accessed

signal isValidChanged

Emitted when the validity of this layer changed.

Added in version 3.16.

keywordList(self) → str

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

Deprecated since version 3.38: Use serverProperties()->:py:func:~QgsMapLayer.keywordList instead.

Return type:

str

signal layerModified

Emitted when modifications has been done on layer

Added in version 3.22.

legend(self) → QgsMapLayerLegend | None

Can be None.

Return type:

Optional[QgsMapLayerLegend]

signal legendChanged

Signal emitted when legend of the layer has changed

legendPlaceholderImage(self) → str

Returns path to the placeholder image or an empty string if a generated legend is shown

Return type:

str

Returns:

placeholder image path

Added in version 3.22.

legendUrl(self) → str

Returns the URL for the layer’s legend.

Deprecated since version 3.44: Use serverProperties()->:py:func:~QgsMapLayer.legendUrl instead.

Return type:

str

legendUrlFormat(self) → str

Returns the format for a URL based layer legend.

Deprecated since version 3.44: Use serverProperties()->:py:func:~QgsMapLayer.legendUrlFormat instead.

Return type:

str

virtual listStylesInDatabase(self)

Lists all the style in db split into related to the layer and not related to

Returns:

• the number of styles related to current layer (-1 on not implemented)

• ids: the list in which will be stored the style db ids

• names: the list in which will be stored the style names

• descriptions: the list in which will be stored the style descriptions

• msgError: a descriptive error message if any occurs

Note

Since QGIS 3.2 Styles related to the layer are ordered with the default style first then by update time for Postgres, MySQL and Spatialite.

virtual loadDefaultMetadata(self)

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)

Returns:

• a string with any status messages

• resultFlag: False if we did not manage to load the default metadata.

virtual loadDefaultStyle(self)

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)

Returns:

• a string with any status messages

• resultFlag: False if we did not manage to load the default style.

See also

loadNamedStyle()

virtual loadNamedMetadata(self, uri: str | None)

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 (Optional[str]) -> (str) – 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.

Returns:

• a string with any status messages

• resultFlag: False if we did not manage to load the default metadata.

loadNamedMetadataFromDatabase(self, db: str | None, uri: str | None, qmd: str | None) → bool

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

Parameters:

• db (Optional[str]) – path to sqlite database

• uri (Optional[str]) – uri for table

• qmd (Optional[str]) – will be set to QMD xml metadata content from database

Return type:

bool

Returns:

True if style was successfully loaded

virtual loadNamedStyle(self, theURI: str | None, loadFromLocalDb: bool, categories: QgsMapLayer.StyleCategories | QgsMapLayer.StyleCategory = QgsMapLayer.AllStyleCategories, flags: Qgis.LoadStyleFlags | Qgis.LoadStyleFlag = Qgis.LoadStyleFlags())

Loads a named style from file/local db/datasource db

Parameters:

• theURI (Optional[str]) – the URI of the style or the URI of the layer

• loadFromLocalDb (bool) – if True forces to load from local db instead of datasource one

• categories (Union[QgsMapLayer.StyleCategories, QgsMapLayer.StyleCategory] = QgsMapLayer.AllStyleCategories) – the style categories to be loaded.

• flags (Union[Qgis.LoadStyleFlags, Qgis.LoadStyleFlag] = Qgis.LoadStyleFlags()) -> (str) – flags controlling how the style should be loaded (since QGIS 3.38)

Returns:

• status message, which may indicate success or contain an error message

• resultFlag: True if a named style is correctly loaded

virtual loadNamedStyle(self, uri: str | None, categories: QgsMapLayer.StyleCategories | QgsMapLayer.StyleCategory = QgsMapLayer.AllStyleCategories, flags: Qgis.LoadStyleFlags | Qgis.LoadStyleFlag = Qgis.LoadStyleFlags())

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 (Optional[str]) – 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.

• categories (Union[QgsMapLayer.StyleCategories, QgsMapLayer.StyleCategory] = QgsMapLayer.AllStyleCategories) – the style categories to be loaded.

• flags (Union[Qgis.LoadStyleFlags, Qgis.LoadStyleFlag] = Qgis.LoadStyleFlags()) -> (str) – flags controlling how the style should be loaded (since QGIS 3.38)

Returns:

• a string with any status messages

• resultFlag: False if we did not manage to load the default style.

See also

loadDefaultStyle()

virtual loadNamedStyleFromDatabase(self, db: str | None, uri: str | None)

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

Parameters:

• db (Optional[str]) – path to sqlite database

• uri (Optional[str]) -> (bool) – uri for table

Returns:

• True if style was successfully loaded

• qml: QML style content from database

virtual loadSldStyle(self, uri: str | None)

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

Parameters:

uri (Optional[str]) -> (str) – uri of source SLD file

Returns:

• a string with any status or error messages

• resultFlag: False if the SLD file could not be loaded

See also

saveSldStyle()

mapTipTemplate(self) → str

The mapTip is a pretty, html representation for feature information.

It may also contain embedded expressions.

Added in version 3.30.

Return type:

str

signal mapTipTemplateChanged

Emitted when the map tip template changes

Added in version 3.30.

mapTipsEnabled(self) → bool

Returns true if map tips are enabled for this layer

Added in version 3.32.

Return type:

bool

signal mapTipsEnabledChanged

Emitted when map tips are enabled or disabled for the layer.

See also

setMapTipsEnabled()

Added in version 3.32.

maximumScale(self) → float

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()

See also

minimumScale()

See also

hasScaleBasedVisibility()

See also

isInScaleRange()

Return type:

float

metadata(self) → QgsLayerMetadata

Returns a reference to the layer’s metadata store.

See also

setMetadata()

See also

metadataChanged()

Return type:

QgsLayerMetadata

signal metadataChanged

Emitted when the layer’s metadata is changed.

See also

setMetadata()

See also

metadata()

virtual metadataUri(self) → str

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)

Return type:

str

Returns:

a string with the metadata file name

metadataUrl(self) → str

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. Since QGIS 3.22, it returns the first metadata URL link.

Return type:

str

Returns:

the layer metadata URL

See also

serverProperties()

Deprecated since version 3.22.

metadataUrlFormat(self) → str

Returns the metadata format of the layer used by QGIS Server in GetCapabilities request. MetadataUrlType indicates how the metadata is structured. Since QGIS 3.22, it returns the first metadata URL format.

Return type:

str

Returns:

the layer metadata format

See also

serverProperties()

Deprecated since version 3.22.

metadataUrlType(self) → str

Returns the metadata type of the layer used by QGIS Server in GetCapabilities request. MetadataUrlType indicates the standard to which the metadata complies. Since QGIS 3.22, it returns the first metadata URL type.

Return type:

str

Returns:

the layer metadata type

See also

serverProperties()

Deprecated since version 3.22.

minimumScale(self) → float

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()

See also

maximumScale()

See also

hasScaleBasedVisibility()

See also

isInScaleRange()

Return type:

float

name(self) → str

Returns the display name of the layer.

See also

setName()

Return type:

str

signal nameChanged

Emitted when the name has been changed

virtual opacity(self) → float

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

See also

setOpacity()

See also

opacityChanged()

Note

Prior to QGIS 3.18, this method was available for vector layers only

Added in version 3.18.

Return type:

float

signal opacityChanged(opacity: float)

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

See also

setOpacity()

See also

opacity()

Note

Prior to QGIS 3.18, this signal was available for vector layers only

Added in version 3.18.

Parameters:

opacity (float)

originalXmlProperties(self) → str

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

Added in version 3.6.

Return type:

str

virtual profileSource(self) → QgsAbstractProfileSource | None

Returns the layer’s profile source if it has profile capabilities. This may be None, depending on the layer type.

Added in version 3.44.

Return type:

Optional[QgsAbstractProfileSource]

project(self) → QgsProject | None

Returns the parent project if this map layer is added to a project. Otherwise returns None

Added in version 3.18.

Return type:

Optional[QgsProject]

virtual properties(self) → Qgis.MapLayerProperties

Returns the map layer properties of this layer.

Note

properties() differ from flags() in that flags() are user settable, and reflect options that users can enable for map layers. In contrast properties() are reflections of inherent capabilities for the layer, which cannot be directly changed by users.

Added in version 3.22.

Return type:

Qgis.MapLayerProperties

providerMetadata(self) → QgsProviderMetadata | None

Returns the layer data provider’s metadata, it may be None.

Added in version 3.40.

Return type:

Optional[QgsProviderMetadata]

static providerReadFlags(layerNode: QDomNode, layerReadFlags: QgsMapLayer.ReadFlags | QgsMapLayer.ReadFlag) → Qgis.DataProviderReadFlags

Returns provider read flag deduced from layer read flags layerReadFlags and a dom node layerNode that describes a layer (corresponding to maplayer tag in a DOM document project file read by QgsProject). This static method is used when loading a project.

Added in version 3.32.

Parameters:

• layerNode (QDomNode)

• layerReadFlags (Union[QgsMapLayer.ReadFlags, QgsMapLayer.ReadFlag])

Return type:

Qgis.DataProviderReadFlags

providerType(self) → str

Returns the provider type (provider key) for this layer

Return type:

str

publicSource(self, hidePassword: bool = False) → str

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.

Parameters:

hidePassword (bool = False) – True to replace the value of credentials with ‘xxxxxxxx’, False to completely remove credentials (key and value). Since QGIS 3.34

See also

source()

Return type:

str

readCommonStyle(self, layerElement: QDomElement, context: QgsReadWriteContext, categories: QgsMapLayer.StyleCategories | QgsMapLayer.StyleCategory = QgsMapLayer.AllStyleCategories)

Read style data common to all layer types

Parameters:

• layerElement (QDomElement)

• context (QgsReadWriteContext)

• categories (Union[QgsMapLayer.StyleCategories, QgsMapLayer.StyleCategory] = QgsMapLayer.AllStyleCategories)

readCustomProperties(self, layerNode: QDomNode, keyStartsWith: str | None = '')

Read custom properties from project file.

Parameters:

• layerNode (QDomNode) – note to read from

• keyStartsWith (Optional[str] = '') – reads only properties starting with the specified string (or all if the string is empty)

readLayerXml(self, layerElement: QDomElement, context: QgsReadWriteContext, flags: QgsMapLayer.ReadFlags | QgsMapLayer.ReadFlag = QgsMapLayer.ReadFlags(), preloadedProvider: QgsDataProvider | None = None) → bool

Sets state from DOM document

Parameters:

• layerElement (QDomElement) – The DOM element corresponding to maplayer tag

• context (QgsReadWriteContext) – writing context (e.g. for conversion between relative and absolute paths)

• flags (Union[QgsMapLayer.ReadFlags, QgsMapLayer.ReadFlag] = QgsMapLayer.ReadFlags()) – optional argument which can be used to control layer reading behavior.

• preloadedProvider (Optional[QgsDataProvider] = None) – optional preloaded data provider that will be used as data provider for this layer, takes ownership (since QGIS 3.32)

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().

Return type:

bool

Returns:

True if successful

readOnly(self) → bool

Returns if this layer is read only.

Return type:

bool

virtual readSld(self, node: QDomNode, errorMessage: str | None) → bool

Parameters:

• node (QDomNode)

• errorMessage (Optional[str])

Return type:

bool

virtual readStyle(self, node: QDomNode, errorMessage: str | None, context: QgsReadWriteContext, categories: QgsMapLayer.StyleCategories | QgsMapLayer.StyleCategory = QgsMapLayer.AllStyleCategories) → bool

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

Parameters:

• node (QDomNode) – node that will contain the style definition for this layer.

• errorMessage (Optional[str]) – reference to string that will be updated with any error messages

• context (QgsReadWriteContext) – reading context (used for transform from relative to absolute paths)

• categories (Union[QgsMapLayer.StyleCategories, QgsMapLayer.StyleCategory] = QgsMapLayer.AllStyleCategories) – the style categories to be read

Return type:

bool

Returns:

True in case of success.

Note

To be implemented in subclasses. Default implementation does nothing and returns False.

readStyleManager(self, layerNode: QDomNode)

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

Parameters:

layerNode (QDomNode)

abstract readSymbology(self, node: QDomNode, errorMessage: str | None, context: QgsReadWriteContext, categories: QgsMapLayer.StyleCategories | QgsMapLayer.StyleCategory = QgsMapLayer.AllStyleCategories) → bool

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

Parameters:

• node (QDomNode) – node that will contain the symbology definition for this layer.

• errorMessage (Optional[str]) – reference to string that will be updated with any error messages

• context (QgsReadWriteContext) – reading context (used for transform from relative to absolute paths)

• categories (Union[QgsMapLayer.StyleCategories, QgsMapLayer.StyleCategory] = QgsMapLayer.AllStyleCategories) – the style categories to be read

Return type:

bool

Returns:

True in case of success.

virtual readXml(self, layer_node: QDomNode, context: QgsReadWriteContext) → bool

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

Parameters:

• layer_node (QDomNode)

• context (QgsReadWriteContext)

Return type:

bool

signal recalculateExtents

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

refreshOnNotifyMessage(self) → str

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

Return type:

str

virtual reload(self)

Synchronises with changes in the datasource

removeCustomProperty(self, key: str | None)

Remove a custom property from layer. Properties are stored in a map and saved in project file.

See also

setCustomProperty()

Parameters:

key (Optional[str])

renderer3D(self) → QgsAbstract3DRenderer | None

Returns 3D renderer associated with the layer. May be None.

Return type:

Optional[QgsAbstract3DRenderer]

signal renderer3DChanged

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

signal rendererChanged

Signal emitted when renderer is changed.

See also

styleChanged()

signal repaintRequested(deferredUpdate: bool = 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. 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.

Parameters:

deferredUpdate (bool = False)

signal request3DUpdate

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

Added in version 3.18.

virtual resolveReferences(self, project: QgsProject | None)

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

Parameters:

project (Optional[QgsProject])

virtual saveDefaultMetadata(self)

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)

Returns:

• a string with any status messages

• resultFlag: False if we did not manage to save the default metadata.

virtual saveDefaultStyle(self, categories: QgsMapLayer.StyleCategories | QgsMapLayer.StyleCategory)

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:

categories (Union[QgsMapLayer.StyleCategories, QgsMapLayer.StyleCategory]) -> (str) – the style categories to be saved (since QGIS 3.26)

Returns:

• a string with any status messages

• resultFlag: False if we did not manage to save the default style.

See also

loadNamedStyle()

See also

saveNamedStyle()

virtual saveDefaultStyle(self)

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)

Returns:

• a string with any status messages

• resultFlag: False if we did not manage to save the default style.

See also

loadNamedStyle()

See also

saveNamedStyle()

Deprecated since version 3.26.

saveNamedMetadata(self, uri: str | None)

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:

uri (Optional[str]) -> (str) – the 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.

Returns:

• a string with any status messages

• resultFlag: False if we did not manage to save the default metadata.

virtual saveNamedStyle(self, uri: str | None, categories: QgsMapLayer.StyleCategories | QgsMapLayer.StyleCategory = QgsMapLayer.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)

Parameters:

• uri (Optional[str]) – the 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.

• categories (Union[QgsMapLayer.StyleCategories, QgsMapLayer.StyleCategory] = QgsMapLayer.AllStyleCategories) -> (str) – the style categories to be saved.

Returns:

• a string with any status messages

• resultFlag: False if we did not manage to save the default style.

See also

saveDefaultStyle()

virtual saveSldStyle(self, uri: str | None)

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

Parameters:

uri (Optional[str]) -> (str) – uri of destination for exported SLD file.

Returns:

• a string with any status or error messages

• resultFlag: False if the SLD file could not be generated

See also

loadSldStyle()

See also

saveSldStyleV2()

virtual saveSldStyleV2(self, exportContext: QgsSldExportContext)

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

Parameters:

exportContext (QgsSldExportContext) -> (str) – SLD export context

Returns:

• a string with any status or error messages

• resultFlag: False if the SLD file could not be generated

See also

loadSldStyle()

Added in version 3.30.

virtual saveStyleToDatabase(self, name: str | None, description: str | None, useAsDefault: bool, uiFileContent: str | None, categories: QgsMapLayer.StyleCategories | QgsMapLayer.StyleCategory = QgsMapLayer.AllStyleCategories) → str

Saves QML and SLD representations of the layer’s style to a table in the database.

Parameters:

• name (Optional[str]) – Style name

• description (Optional[str]) – A description of the style

• useAsDefault (bool) – Set to True if style should be used as the default style for the layer

• uiFileContent (Optional[str])

• categories (Union[QgsMapLayer.StyleCategories, QgsMapLayer.StyleCategory] = QgsMapLayer.AllStyleCategories) – the style categories to be saved.

Note

Prior to QGIS 3.24, this method would show a message box warning when a style with the same styleName already existed to confirm replacing the style with the user. Since 3.24, calling this method will ALWAYS overwrite any existing style with the same name. Use QgsProviderRegistry.styleExists() to test in advance if a style already exists and handle this appropriately in your client code.

Return type:

str

Returns:

• msgError: a descriptive error message if any occurs

Deprecated since version 4.0: Use saveStyleToDatabaseV2() instead.

saveStyleToDatabaseV2(self, name: str | None, description: str | None, useAsDefault: bool, uiFileContent: str | None, categories: QgsMapLayer.StyleCategories | QgsMapLayer.StyleCategory = QgsMapLayer.AllStyleCategories)

Saves QML and SLD representations of the layer’s style to a table in the database.

Parameters:

• name (Optional[str]) – Style name

• description (Optional[str]) – A description of the style

• useAsDefault (bool) – Set to True if style should be used as the default style for the layer

• uiFileContent (Optional[str])

• categories (Union[QgsMapLayer.StyleCategories, QgsMapLayer.StyleCategory] = QgsMapLayer.AllStyleCategories) -> (QgsMapLayer.SaveStyleResults) – the style categories to be saved.

Returns:

• flags representing whether QML or SLD storing was successful

• msgError: a descriptive error message if any occurs

Added in version 4.0.

virtual selectionProperties(self) → QgsMapLayerSelectionProperties | None

Returns the layer’s selection properties. This may be None, depending on the layer type.

Added in version 3.34.

Return type:

Optional[QgsMapLayerSelectionProperties]

serverProperties(self) → QgsMapLayerServerProperties | None

Returns QGIS Server Properties for the map layer

Added in version 3.22.

Return type:

Optional[QgsMapLayerServerProperties]

setAbstract(self, abstract: str | None)

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

Deprecated since version 3.38: Use serverProperties()->:py:func:~QgsMapLayer.setAbstract instead.

Parameters:

abstract (Optional[str])

setAttribution(self, attrib: str | None)

Sets the attribution of the layerused by QGIS Server in GetCapabilities request.

Deprecated since version 3.38: Use serverProperties()->:py:func:~QgsMapLayer.setAttribution instead.

Parameters:

attrib (Optional[str])

setAttributionUrl(self, attribUrl: str | None)

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

Deprecated since version 3.38: Use serverProperties()->:py:func:~QgsMapLayer.setAttributionUrl instead.

Parameters:

attribUrl (Optional[str])

setAutoRefreshEnabled(self, enabled: bool)

Sets whether auto refresh is enabled for the layer.

See also

hasAutoRefreshEnabled()

See also

setAutoRefreshInterval()

Deprecated since version 3.40: Use setAutoRefreshMode() instead.

Parameters:

enabled (bool)

setAutoRefreshInterval(self, interval: int)

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 setAutoRefreshMode().

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()

See also

setAutoRefreshEnabled()

Parameters:

interval (int)

setAutoRefreshMode(self, mode: Qgis.AutoRefreshMode)

Sets the automatic refresh mode for the layer.

See also

autoRefreshMode()

See also

setAutoRefreshInterval()

Added in version 3.34.

Parameters:

mode (Qgis.AutoRefreshMode)

setBlendMode(self, blendMode: QPainter.CompositionMode)

Set the blending mode used for rendering a layer.

Parameters:

blendMode (QPainter.CompositionMode) – new blending mode

See also

blendMode()

setCrs(self, srs: QgsCoordinateReferenceSystem, emitSignal: bool = True)

Sets layer’s spatial reference system.

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

See also

crs()

See also

crsChanged()

See also

setVerticalCrs()

Parameters:

• srs (QgsCoordinateReferenceSystem)

• emitSignal (bool = True)

setCustomProperties(self, properties: QgsObjectCustomProperties)

Set custom properties for layer. Current properties are dropped.

Parameters:

properties (QgsObjectCustomProperties)

setCustomProperty(self, key: str | None, value: Any)

Set a custom property for layer. Properties are stored in a map and saved in project file.

See also

customProperty()

See also

removeCustomProperty()

Parameters:

• key (Optional[str])

• value (Any)

setDataSource(self, dataSource: str | None, baseName: str | None = '', provider: str | None = '', loadDefaultStyleFlag: bool = False)

Updates the data source of the layer.

The dataSource argument must specify the new data source string for the layer. The format varies depending on the specified data provider in use. See QgsDataSourceUri and the documentation for the various QgsMapLayer subclasses for further details on data source strings.

The baseName argument specifies the user-visible name to use for the layer. (See name() or setName()). If not specified, then the current name will be left unchanged (since QGIS 3.40).

The provider argument is used to specify the unique key of the data provider to use for the layer. This must match one of the values returned by QgsProviderRegistry.instance()->:py:func:~QgsMapLayer.providerList. (See providerType()). If not specified, then the current data provider will be used (since QGIS 3.40).

If loadDefaultStyleFlag is set to True then the layer’s existing style will be reset to the default for the data source.

Note

If loadDefaultStyleFlag is False then 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.

After setting a new data source callers can test isValid() to determine whether the new source and provider are valid and ready for use. If setting the new data source fails and the layer returns False to isValid(), then descriptive errors relating to setting the data source can be retrieved by calling error().

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

See also

dataSourceChanged()

Added in version 3.20.

Parameters:

• dataSource (Optional[str])

• baseName (Optional[str] = '')

• provider (Optional[str] = '')

• loadDefaultStyleFlag (bool = False)

setDataSource(self, dataSource: str | None, baseName: str | None, provider: str | None, options: QgsDataProvider.ProviderOptions, loadDefaultStyleFlag: bool = False)

Updates the data source of the layer.

The dataSource argument must specify the new data source string for the layer. The format varies depending on the specified data provider in use. See QgsDataSourceUri and the documentation for the various QgsMapLayer subclasses for further details on data source strings.

The baseName argument specifies the user-visible name to use for the layer. (See name() or setName()).

The provider argument is used to specify the unique key of the data provider to use for the layer. This must match one of the values returned by QgsProviderRegistry.instance()->:py:func:~QgsMapLayer.providerList. (See providerType()).

The options argument can be used to pass additional layer properties to the new data provider.

If loadDefaultStyleFlag is set to True then the layer’s existing style will be reset to the default for the data source.

Note

If loadDefaultStyleFlag is False then 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.

After setting a new data source callers can test isValid() to determine whether the new source and provider are valid and ready for use. If setting the new data source fails and the layer returns False to isValid(), then descriptive errors relating to setting the data source can be retrieved by calling error().

See also

dataSourceChanged()

Added in version 3.6.

Parameters:

• dataSource (Optional[str])

• baseName (Optional[str])

• provider (Optional[str])

• options (QgsDataProvider.ProviderOptions)

• loadDefaultStyleFlag (bool = False)

setDataSource(self, dataSource: str | None, baseName: str | None, provider: str | None, options: QgsDataProvider.ProviderOptions, flags: Qgis.DataProviderReadFlags | Qgis.DataProviderReadFlag)

Updates the data source of the layer.

The dataSource argument must specify the new data source string for the layer. The format varies depending on the specified data provider in use. See QgsDataSourceUri and the documentation for the various QgsMapLayer subclasses for further details on data source strings.

The baseName argument specifies the user-visible name to use for the layer. (See name() or setName()).

The provider argument is used to specify the unique key of the data provider to use for the layer. This must match one of the values returned by QgsProviderRegistry.instance()->:py:func:~QgsMapLayer.providerList. (See providerType()).

The options argument can be used to pass additional layer properties to the new data provider.

The flags argument specifies provider read flags which control the data provider construction, such as QgsDataProvider.ReadFlag.FlagTrustDataSource, QgsDataProvider.ReadFlag.FlagLoadDefaultStyle, etc.

Note

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.

After setting a new data source callers can test isValid() to determine whether the new source and provider are valid and ready for use. If setting the new data source fails and the layer returns False to isValid(), then descriptive errors relating to setting the data source can be retrieved by calling error().

See also

dataSourceChanged()

Added in version 3.20.

Parameters:

• dataSource (Optional[str])

• baseName (Optional[str])

• provider (Optional[str])

• options (QgsDataProvider.ProviderOptions)

• flags (Union[Qgis.DataProviderReadFlags, Qgis.DataProviderReadFlag])

setDataUrl(self, dataUrl: str | None)

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

Deprecated since version 3.38: Use serverProperties()->:py:func:~QgsMapLayer.setDataUrl instead.

Parameters:

dataUrl (Optional[str])

setDataUrlFormat(self, dataUrlFormat: str | None)

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

Deprecated since version 3.38: Use serverProperties()->:py:func:~QgsMapLayer.setDataUrlFormat instead.

Parameters:

dataUrlFormat (Optional[str])

virtual setDependencies(self, layers: Iterable[QgsMapLayerDependency]) → bool

Sets the list of dependencies.

See also

dependencies()

Parameters:

layers (Iterable[QgsMapLayerDependency]) – set of QgsMapLayerDependency. Only user-defined dependencies will be added

Return type:

bool

Returns:

False if a dependency cycle has been detected

setError(self, error: QgsError)

Sets error message

Parameters:

error (QgsError)

virtual setExtent(self, rect: QgsRectangle)

Sets the extent

Parameters:

rect (QgsRectangle)

virtual setExtent3D(self, box: QgsBox3D)

Sets the extent

Added in version 3.36.

Parameters:

box (QgsBox3D)

setFlags(self, flags: QgsMapLayer.LayerFlags | QgsMapLayer.LayerFlag)

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.

See also

properties()

Added in version 3.4.

Parameters:

flags (Union[QgsMapLayer.LayerFlags, QgsMapLayer.LayerFlag])

setId(self, id: str | None) → bool

Sets the layer’s id.

Returns True if the layer ID was successfully changed, or False if it could not be changed (e.g. because the layer is owned by a QgsProject or QgsMapLayerStore).

Warning

It is the caller’s responsibility to ensure that the layer ID is unique in the desired context. Generally this method should not be called, and the auto generated ID should be used instead.

Warning

This method should not be called on layers which already belong to a QgsProject or QgsMapLayerStore.

See also

id()

See also

idChanged()

Added in version 3.38.

Parameters:

id (Optional[str])

Return type:

bool

setKeywordList(self, keywords: str | None)

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

Deprecated since version 3.38: Use serverProperties()->:py:func:~QgsMapLayer.setKeywordList instead.

Parameters:

keywords (Optional[str])

virtual setLayerOrder(self, layers: Iterable[str | None])

Reorders the previously selected sublayers of this layer from bottom to top. (Useful for providers that manage their own layers, such as WMS).

Parameters:

layers (Iterable[Optional[str]])

setLegend(self, legend: QgsMapLayerLegend | None)

Assign a legend controller to the map layer. The object will be responsible for providing legend items.

Parameters:

legend (Optional[QgsMapLayerLegend]) – Takes ownership of the object. Can be None.

setLegendPlaceholderImage(self, imgPath: str | None)

Set placeholder image for legend. If the string is empty, a generated legend will be shown.

Parameters:

imgPath (Optional[str]) – file path to the placeholder image

Added in version 3.22.

setLegendUrl(self, legendUrl: str | None)

Sets the URL for the layer’s legend.

Deprecated since version 3.44: Use serverProperties()->:py:func:~QgsMapLayer.setLegendUrl instead.

Parameters:

legendUrl (Optional[str])

setLegendUrlFormat(self, legendUrlFormat: str | None)

Sets the format for a URL based layer legend.

Deprecated since version 3.44: Use serverProperties()->:py:func:~QgsMapLayer.setLegendUrlFormat instead.

Parameters:

legendUrlFormat (Optional[str])

setMapTipTemplate(self, mapTipTemplate: str | None)

The mapTip is a pretty, html representation for feature information.

It may also contain embedded expressions.

Added in version 3.30.

Parameters:

mapTipTemplate (Optional[str])

setMapTipsEnabled(self, enabled: bool)

Enable or disable map tips for this layer

Parameters:

enabled (bool) – Whether map tips are enabled for this layer

Added in version 3.32.

setMaximumScale(self, scale: float)

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()

See also

setMinimumScale()

See also

setScaleBasedVisibility()

Parameters:

scale (float)

virtual setMetadata(self, metadata: QgsLayerMetadata)

Sets the layer’s metadata store.

See also

metadata()

See also

metadataChanged()

Parameters:

metadata (QgsLayerMetadata)

setMetadataUrl(self, metaUrl: str | None)

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. Since QGIS 3.22, it edits the first metadata URL link.

See also

serverProperties()

Deprecated since version 3.22.

Parameters:

metaUrl (Optional[str])

setMetadataUrlFormat(self, metaUrlFormat: str | None)

Sets the metadata format of the layer used by QGIS Server in GetCapabilities request. MetadataUrlType indicates how the metadata is structured. Since QGIS 3.22, it edits the first metadata URL format.

See also

serverProperties()

Deprecated since version 3.22.

Parameters:

metaUrlFormat (Optional[str])

setMetadataUrlType(self, metaUrlType: str | None)

Set the metadata type of the layer used by QGIS Server in GetCapabilities request MetadataUrlType indicates the standard to which the metadata complies. Since QGIS 3.22, it edits the first metadata URL type.

See also

serverProperties()

Deprecated since version 3.22.

Parameters:

metaUrlType (Optional[str])

setMinimumScale(self, scale: float)

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()

See also

setMaximumScale()

See also

setScaleBasedVisibility()

Parameters:

scale (float)

setName(self, name: str | None)

Set the display name of the layer.

See also

name()

Parameters:

name (Optional[str])

virtual setOpacity(self, opacity: float)

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

See also

opacity()

See also

opacityChanged()

Note

Prior to QGIS 3.18, this method was available for vector layers only

Added in version 3.18.

Parameters:

opacity (float)

setOriginalXmlProperties(self, originalXmlProperties: str | None)

Sets the original XML properties for the layer to originalXmlProperties

The storage format for the XML is qlr

Added in version 3.6.

Parameters:

originalXmlProperties (Optional[str])

setProviderType(self, providerType: str | None)

Sets the providerType (provider key)

Parameters:

providerType (Optional[str])

setRefreshOnNofifyMessage(self, message: str | None)

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:param message:

Parameters:

message (Optional[str])

setRefreshOnNotifyEnabled(self, enabled: bool)

Set whether provider notification is connected to triggerRepaint

Parameters:

enabled (bool)

setRenderer3D(self, renderer: QgsAbstract3DRenderer | None)

Sets 3D renderer for the layer. Takes ownership of the renderer.

Parameters:

renderer (Optional[QgsAbstract3DRenderer])

setScaleBasedVisibility(self, enabled: bool)

Sets whether scale based visibility is enabled for the layer.

Parameters:

enabled (bool) – set to True to enable scale based visibility

See also

setMinimumScale()

See also

setMaximumScale()

See also

hasScaleBasedVisibility()

setShortName(self, shortName: str | None)

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

Deprecated since version 3.38: Use serverProperties()->:py:func:~QgsMapLayer.setShortName instead.

Parameters:

shortName (Optional[str])

virtual setSubLayerVisibility(self, name: str | None, visible: bool)

Set the visibility of the given sublayer name.

Parameters:

• name (Optional[str]) – sublayer name

• visible (bool) – sublayer visibility

setTitle(self, title: str | None)

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

Deprecated since version 3.38: Use serverProperties()->:py:func:~QgsMapLayer.setTitle instead.

Parameters:

title (Optional[str])

abstract setTransformContext(self, transformContext: QgsCoordinateTransformContext)

Sets the coordinate transform context to transformContext

Added in version 3.8.

Parameters:

transformContext (QgsCoordinateTransformContext)

setValid(self, valid: bool)

Sets whether layer is valid or not

Parameters:

valid (bool)

setVerticalCrs(self, crs: QgsCoordinateReferenceSystem)

Sets the layer’s vertical coordinate reference system.

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

Note

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

Parameters:

crs (QgsCoordinateReferenceSystem) -> (bool) – the vertical CRS

Returns:

• True if vertical CRS was successfully set

• errorMessage: a descriptive message if the vertical CRS could not be set

See also

verticalCrs()

See also

setCrs()

Added in version 3.38.

shortName(self) → str

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

Deprecated since version 3.38: Use serverProperties()->:py:func:~QgsMapLayer.shortName instead.

Return type:

str

source(self) → str

Returns the source for the layer. This source may contain usernames, passwords and other sensitive information.

See also

publicSource()

Return type:

str

signal statusChanged(status: str)

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

Parameters:

status (str)

signal styleChanged

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()

signal styleLoaded(categories: QgsMapLayer.StyleCategories)

Emitted when a style has been loaded

Parameters:

categories (QgsMapLayer.StyleCategories) – style categories

Added in version 3.12.

styleManager(self) → QgsMapLayerStyleManager | None

Gets access to the layer’s style manager. Style manager allows switching between multiple styles.

Return type:

Optional[QgsMapLayerStyleManager]

virtual styleURI(self) → str

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)

Return type:

str

Returns:

a string with the style file name

See also

loadNamedStyle()

See also

saveNamedStyle()

virtual subLayers(self) → List[str]

Returns the sublayers of this layer. (Useful for providers that manage their own layers, such as WMS).

Return type:

List[str]

virtual supportsEditing(self) → bool

Returns whether the layer supports editing or not.

Return type:

bool

Returns:

False if the layer is read only or the data provider has no editing capabilities.

Note

default implementation returns False.

Added in version 3.22.

virtual temporalProperties(self) → QgsMapLayerTemporalProperties | None

Returns the layer’s temporal properties. This may be None, depending on the layer type.

Added in version 3.14.

Return type:

Optional[QgsMapLayerTemporalProperties]

virtual timestamp(self) → QDateTime

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

Return type:

QDateTime

title(self) → str

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

Deprecated since version 3.38: Use serverProperties()->:py:func:~QgsMapLayer.title instead.

Return type:

str

transformContext(self) → QgsCoordinateTransformContext

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

Added in version 3.8.

Return type:

QgsCoordinateTransformContext

trigger3DUpdate(self)

Will advise any 3D maps that this layer requires to be updated in the scene. Will emit a request3DUpdate() signal.

Added in version 3.18.

triggerRepaint(self, deferredUpdate: bool = False)

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

Parameters:

deferredUpdate (bool = False)

type(self) → Qgis.LayerType

Returns the type of the layer.

Return type:

Qgis.LayerType

undoStack(self) → QUndoStack | None

Returns pointer to layer’s undo stack

Return type:

Optional[QUndoStack]

undoStackStyles(self) → QUndoStack | None

Returns pointer to layer’s style undo stack

Return type:

Optional[QUndoStack]

verticalCrs(self) → QgsCoordinateReferenceSystem

Returns the layer’s vertical coordinate reference system.

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

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

Note

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

See also

crs()

See also

crs3D()

See also

setVerticalCrs()

Added in version 3.38.

Return type:

QgsCoordinateReferenceSystem

signal verticalCrsChanged

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

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

See also

crsChanged()

See also

crs3DChanged()

See also

setCrs()

See also

setVerticalCrs()

See also

verticalCrs()

Added in version 3.38.

wgs84Extent(self, forceRecalculate: bool = False) → QgsRectangle

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:

forceRecalculate (bool = False) – True to return the current WGS84 extent whatever the read flags

Added in version 3.20.

Return type:

QgsRectangle

signal 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.

writeCommonStyle(self, layerElement: QDomElement, document: QDomDocument, context: QgsReadWriteContext, categories: QgsMapLayer.StyleCategories | QgsMapLayer.StyleCategory = QgsMapLayer.AllStyleCategories)

Write style data common to all layer types

Parameters:

• layerElement (QDomElement)

• document (QDomDocument)

• context (QgsReadWriteContext)

• categories (Union[QgsMapLayer.StyleCategories, QgsMapLayer.StyleCategory] = QgsMapLayer.AllStyleCategories)

writeCustomProperties(self, layerNode: QDomNode, doc: QDomDocument)

Write custom properties to project file.

Parameters:

• layerNode (QDomNode)

• doc (QDomDocument)

writeLayerXml(self, layerElement: QDomElement, document: QDomDocument, context: QgsReadWriteContext) → bool

Stores state in DOM node

Parameters:

• layerElement (QDomElement) – is a DOM element corresponding to maplayer tag

• document (QDomDocument) – is a the DOM document being written

• context (QgsReadWriteContext) – reading 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().

Return type:

bool

Returns:

True if successful

virtual writeStyle(self, node: QDomNode, doc: QDomDocument, errorMessage: str | None, context: QgsReadWriteContext, categories: QgsMapLayer.StyleCategories | QgsMapLayer.StyleCategory = QgsMapLayer.AllStyleCategories) → bool

Write just the symbology information for the layer into the document

Parameters:

• node (QDomNode) – the node that will have the style element added to it.

• doc (QDomDocument) – the document that will have the QDomNode added.

• errorMessage (Optional[str]) – reference to string that will be updated with any error messages

• context (QgsReadWriteContext) – writing context (used for transform from absolute to relative paths)

• categories (Union[QgsMapLayer.StyleCategories, QgsMapLayer.StyleCategory] = QgsMapLayer.AllStyleCategories) – the style categories to be written

Return type:

bool

Returns:

True in case of success.

Note

To be implemented in subclasses. Default implementation does nothing and returns False.

Note

There is a confusion of terms with the GUI. This method actually writes what is known as the symbology in the application.

writeStyleManager(self, layerNode: QDomNode, doc: QDomDocument)

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

Parameters:

• layerNode (QDomNode)

• doc (QDomDocument)

abstract writeSymbology(self, node: QDomNode, doc: QDomDocument, errorMessage: str | None, context: QgsReadWriteContext, categories: QgsMapLayer.StyleCategories | QgsMapLayer.StyleCategory = QgsMapLayer.AllStyleCategories) → bool

Write the style for the layer into the document provided.

Parameters:

• node (QDomNode) – the node that will have the style element added to it.

• doc (QDomDocument) – the document that will have the QDomNode added.

• errorMessage (Optional[str]) – reference to string that will be updated with any error messages

• context (QgsReadWriteContext) – writing context (used for transform from absolute to relative paths)

• categories (Union[QgsMapLayer.StyleCategories, QgsMapLayer.StyleCategory] = QgsMapLayer.AllStyleCategories) – the 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.

Return type:

bool

Returns:

True in case of success.

virtual writeXml(self, layer_node: QDomNode, document: QDomDocument, context: QgsReadWriteContext) → bool

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

Parameters:

• layer_node (QDomNode)

• document (QDomDocument)

• context (QgsReadWriteContext)

Return type:

bool