Class: QgsMapLayerLegend

The QgsMapLayerLegend class is abstract interface for implementations of legends for one map layer.

Class Hierarchy

Base classes

QObject

Subclasses

QgsDefaultMeshLayerLegend	Default legend implementation for mesh layers
QgsDefaultPointCloudLayerLegend	Default legend implementation for point cloud layers
QgsDefaultRasterLayerLegend	Default legend implementation for raster layers
QgsDefaultVectorLayerLegend	Default legend implementation for vector layers

Methods

createLayerTreeModelLegendNodes	Returns list of legend nodes to be used for a particular layer tree layer node.
readXml	Reads configuration from a DOM element previously written by writeXml()
writeXml	Writes configuration to a DOM element, to be used later with readXml()

Static Methods

defaultMeshLegend	Create new legend implementation for mesh layer
defaultPointCloudLegend	Create new legend implementation for a point cloud layer.
defaultRasterLegend	Create new legend implementation for raster layer
defaultVectorLegend	Create new legend implementation for vector layer

Signals

itemsChanged

Emitted when existing items/nodes got invalid and should be replaced by new ones

class qgis.core.QgsMapLayerLegend

Bases: QObject

__init__(parent: QObject | None = None)

Constructor for QgsMapLayerLegend

Parameters:

parent (Optional[QObject] = None)

createLayerTreeModelLegendNodes(self, nodeLayer: QgsLayerTreeLayer | None) → List[QgsLayerTreeModelLegendNode]

Returns list of legend nodes to be used for a particular layer tree layer node. Ownership is transferred to the caller.

Parameters:

nodeLayer (Optional[QgsLayerTreeLayer])

Return type:

List[QgsLayerTreeModelLegendNode]

static defaultMeshLegend(ml: QgsMeshLayer | None) → QgsMapLayerLegend | None

Create new legend implementation for mesh layer

Parameters:

ml (Optional[QgsMeshLayer])

Return type:

Optional[QgsMapLayerLegend]

static defaultPointCloudLegend(layer: QgsPointCloudLayer | None) → QgsMapLayerLegend | None

Create new legend implementation for a point cloud layer.

Added in version 3.18.

Parameters:

layer (Optional[QgsPointCloudLayer])

Return type:

Optional[QgsMapLayerLegend]

static defaultRasterLegend(rl: QgsRasterLayer | None) → QgsMapLayerLegend | None

Create new legend implementation for raster layer

Parameters:

rl (Optional[QgsRasterLayer])

Return type:

Optional[QgsMapLayerLegend]

static defaultVectorLegend(vl: QgsVectorLayer | None) → QgsMapLayerLegend | None

Create new legend implementation for vector layer

Parameters:

vl (Optional[QgsVectorLayer])

Return type:

Optional[QgsMapLayerLegend]

signal itemsChanged

Emitted when existing items/nodes got invalid and should be replaced by new ones

readXml(self, elem: QDomElement, context: QgsReadWriteContext)

Reads configuration from a DOM element previously written by writeXml()

Added in version 3.2.

Parameters:

• elem (QDomElement)

• context (QgsReadWriteContext)

writeXml(self, doc: QDomDocument, context: QgsReadWriteContext) → QDomElement

Writes configuration to a DOM element, to be used later with readXml()

Added in version 3.2.

Parameters:

• doc (QDomDocument)

• context (QgsReadWriteContext)

Return type:

QDomElement