Class: QgsAnnotationLayer¶

class qgis.core.QgsAnnotationLayer(name: str, options: QgsAnnotationLayer.LayerOptions)¶

Bases: QgsMapLayer

Constructor for a new QgsAnnotationLayer with the specified layer name.

The options argument specifies load-time layer options.

Represents a map layer containing a set of georeferenced annotations, e.g. markers, lines, polygons or text items.

Annotation layers store a set of QgsAnnotationItem items, which are rendered according to the item’s z-order.

New in version 3.16:

Methods

`addItem`	Adds an `item` to the layer.
`appendError`	Add error message
`childEvent`
`clear`	Removes all items from the layer.
`clone`	rtype QgsAnnotationLayer
`connectNotify`
`createMapRenderer`	param rendererContext
`customEvent`
`decodedSource`	Called by `readLayerXML()`, used by derived classes to decode provider's specific data source from project files.
`disconnectNotify`
`encodedSource`	Called by `writeLayerXML()`, used by derived classes to encode provider's specific data source to project files.
`extent`	rtype QgsRectangle
`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.
`isEmpty`	Returns `True` if the annotation layer is empty and contains no annotations.
`isSignalConnected`
`items`	Returns a map of items contained in the layer, by unique item ID.
`opacity`	Returns the opacity for the annotation layer, where opacity is a value between 0 (totally transparent) and 1.0 (fully opaque).
`readCommonStyle`	Read style data common to all layer types
`readCustomProperties`	Read custom properties from project file.
`readStyleManager`	Read style manager's configuration (if any).
`readSymbology`	param node
`readXml`	param layerNode
`receivers`
`removeItem`	Removes (and deletes) the item with matching `id`.
`reset`	Resets the annotation layer to a default state, and clears all items from it.
`sender`
`senderSignalIndex`
`setError`	Sets error message
`setExtent`	Sets the extent
`setOpacity`	Sets the `opacity` for the annotation layer, where `opacity` is a value between 0 (totally transparent) and 1.0 (fully opaque).
`setProviderType`	Sets the `providerType` (provider key)
`setTransformContext`	param context
`setValid`	Sets whether layer is valid or not
`timerEvent`
`writeCommonStyle`	Write style data common to all layer types
`writeCustomProperties`	Write custom properties to project file.
`writeStyleManager`	Write style manager's configuration (if exists).
`writeSymbology`	param node
`writeXml`	param layer_node

class LayerOptions(transformContext: QgsCoordinateTransformContext)¶

Bases: sip.wrapper

Constructor for LayerOptions.

QgsAnnotationLayer.LayerOptions(QgsAnnotationLayer.LayerOptions)

transformContext¶

addItem(self, item: QgsAnnotationItem) → str¶

Adds an item to the layer.

Ownership of item is transferred to the layer.

Returns the unique ID assigned to the item.

Parameters: item (QgsAnnotationItem) –
Return type: str

appendError(self, error: QgsErrorMessage)¶: Add error message

childEvent(self, QChildEvent)¶

clear(self)¶: Removes all items from the layer.

clone(self) → QgsAnnotationLayer¶

Return type: QgsAnnotationLayer

connectNotify(self, QMetaMethod)¶

createMapRenderer(self, rendererContext: QgsRenderContext) → QgsMapLayerRenderer¶

Parameters: rendererContext (QgsRenderContext) –
Return type: QgsMapLayerRenderer

customEvent(self, QEvent)¶

decodedSource(self, source: str, dataProvider: str, 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 – data source to decode, typically read from layer’s DOM element “datasource”
dataProvider – string identification of data provider (e.g. “ogr”), typically read from layer’s DOM element
context – reading context (e.g. for conversion between relative and absolute paths)

Returns

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

New in version 3.2.

disconnectNotify(self, QMetaMethod)¶

encodedSource(self, source: str, 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 – data source to encode, typically QgsMapLayer.source()
context – writing context (e.g. for conversion between relative and absolute paths)

Returns

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

New in version 3.2.

extent(self) → QgsRectangle¶

Return type: QgsRectangle

hasDependencyCycle(self, 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 QGIS: 3.10

isEmpty(self) → bool¶

Returns True if the annotation layer is empty and contains no annotations.

Return type: bool

isSignalConnected(self, QMetaMethod) → bool¶

items(self) → object¶

Returns a map of items contained in the layer, by unique item ID.

This map contains references to items owned by the layer, and ownership of these remains with the layer.

Return type: object

opacity(self) → float¶

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