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.

Parameters
  • name (str) –

  • options

class LayerOptions(transformContext: QgsCoordinateTransformContext)

Bases: sip.wrapper

Constructor for LayerOptions.

QgsAnnotationLayer.LayerOptions(QgsAnnotationLayer.LayerOptions)

Parameters

transformContext (QgsCoordinateTransformContext) –

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

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

Read style data common to all layer types

New in version 3.0.

readCustomProperties(self, layerNode: QDomNode, keyStartsWith: str = '')

Read custom properties from project file.

Parameters
  • layerNode – note to read from

  • keyStartsWith – reads only properties starting with the specified string (or all if the string is empty)

readStyleManager(self, layerNode: QDomNode)

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

readSymbology(self, node: QDomNode, errorMessage: str, context: QgsReadWriteContext, categories: Union[QgsMapLayer.StyleCategories, QgsMapLayer.StyleCategory] = QgsMapLayer.AllStyleCategories) → bool
Parameters
Return type

bool

readXml(self, layerNode: QDomNode, context: QgsReadWriteContext) → bool
Parameters
Return type

bool

receivers(self, PYQT_SIGNAL) → int
removeItem(self, id: str) → bool

Removes (and deletes) the item with matching id.

Parameters

id (str) –

Return type

bool

reset(self)

Resets the annotation layer to a default state, and clears all items from it.

sender(self) → QObject
senderSignalIndex(self) → int
setError(self, error: QgsError)

Sets error message

setExtent(self, rect: QgsRectangle)

Sets the extent

setProviderType(self, providerType: str)

Sets the providerType (provider key)

setTransformContext(self, context: QgsCoordinateTransformContext)
Parameters

context (QgsCoordinateTransformContext) –

setValid(self, valid: bool)

Sets whether layer is valid or not

timerEvent(self, QTimerEvent)
writeCommonStyle(self, layerElement: QDomElement, document: QDomDocument, context: QgsReadWriteContext, categories: Union[QgsMapLayer.StyleCategories, QgsMapLayer.StyleCategory] = QgsMapLayer.AllStyleCategories)

Write style data common to all layer types

New in version 3.0.

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

Write custom properties to project file.

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

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

writeSymbology(self, node: QDomNode, doc: QDomDocument, errorMessage: str, a3: QgsReadWriteContext, categories: Union[QgsMapLayer.StyleCategories, QgsMapLayer.StyleCategory] = QgsMapLayer.AllStyleCategories) → bool
Parameters
Return type

bool

writeXml(self, layer_node: QDomNode, doc: QDomDocument, context: QgsReadWriteContext) → bool
Parameters
Return type

bool