Class: QgsMapLayerUtils¶

Contains utility functions for working with map layers.

Added in version 3.20.

Static Methods

`combinedExtent`	Returns the combined extent of a list of layers.
`databaseConnection`	Creates and returns the (possibly `None`) database connection for a layer.
`isOpenStreetMapLayer`	Returns `True` if the layer is served by OpenStreetMap server.
`launderLayerName`	Launders a layer's name, converting it into a format which is general suitable for file names or database layer names.
`layerSourceMatchesPath`	Returns `True` if the source of the specified layer matches the given path.
`sortLayersByType`	Sorts a list of map layers by their layer type, respecting the order of types specified.
`updateLayerSourcePath`	Updates a layer's data source, replacing its data source with a path referring to newPath.

class qgis.core.QgsMapLayerUtils[source]¶

Bases: object

static combinedExtent(layers: Iterable[QgsMapLayer], crs: QgsCoordinateReferenceSystem, transformContext: QgsCoordinateTransformContext) → QgsRectangle[source]¶

Returns the combined extent of a list of layers.

The crs argument specifies the desired coordinate reference system for the combined extent.

Parameters:

layers (Iterable[QgsMapLayer])
crs (QgsCoordinateReferenceSystem)
transformContext (QgsCoordinateTransformContext)

Return type:

QgsRectangle

static databaseConnection(layer: QgsMapLayer | None) → QgsAbstractDatabaseProviderConnection | None[source]¶

Creates and returns the (possibly None) database connection for a layer. Ownership is transferred to the caller.

Added in version 3.22.

Parameters:: layer (Optional[QgsMapLayer])
Return type:: Optional[QgsAbstractDatabaseProviderConnection]

static isOpenStreetMapLayer(layer: QgsMapLayer | None) → bool[source]¶

Returns True if the layer is served by OpenStreetMap server.

Added in version 3.40.

Parameters:: layer (Optional[QgsMapLayer])
Return type:: bool

static launderLayerName(name: str | None) → str[source]¶

Launders a layer’s name, converting it into a format which is general suitable for file names or database layer names.

Specifically this method:

Converts the name to lowercase
Replaces spaces by underscore characters
Removes any characters which are not alphanumeric or ‘_’.

Added in version 3.28.

Parameters:: name (Optional[str])
Return type:: str

static layerSourceMatchesPath(layer: QgsMapLayer | None, path: str | None) → bool[source]¶

Returns True if the source of the specified layer matches the given path.

This method can be used to test whether a layer is associated with a file path.

Added in version 3.22.

Parameters:

layer (Optional[QgsMapLayer])
path (Optional[str])

Return type:

bool

static sortLayersByType(layers: Iterable[QgsMapLayer], order: Iterable[Qgis.LayerType]) → List[QgsMapLayer]¶

Sorts a list of map layers by their layer type, respecting the order of types specified.

Layer types which appear earlier in the order list will result in matching layers appearing earlier in the result list.

Added in version 3.26.

Parameters:

layers (Iterable[QgsMapLayer])
order (Iterable[Qgis.LayerType])

Return type:

List[QgsMapLayer]

static updateLayerSourcePath(layer: QgsMapLayer | None, newPath: str | None) → bool[source]¶

Updates a layer’s data source, replacing its data source with a path referring to newPath.

Returns True if the layer was updated, or False if the layer was not updated (e.g. it uses a data provider which does not specify paths in a layer URI.

Added in version 3.22.

Parameters:

layer (Optional[QgsMapLayer])
newPath (Optional[str])

Return type:

bool