Class: QgsMergedFeatureRenderer¶
- class qgis.core.QgsMergedFeatureRenderer¶
Bases:
QgsFeatureRenderer
QgsMergedFeatureRenderer
is a polygon or line-only feature renderer used to renderer a set of features merged (or dissolved) into a single geometry.It is designed on top of another feature renderer, which is called “embedded” Most of the methods are then only proxies to the embedded renderer. E.g. if the embedded renderer is a categorized renderer, then all the matching features for each categorized class will be dissolved together. Features from different classes will NOT be dissolved together.
New in version 3.18.
QgsMergedFeatureRenderer(embeddedRenderer:
QgsFeatureRenderer
) Constructor for QgsMergedFeatureRenderer.- Parameters:
embeddedRenderer – optional embeddedRenderer. Ownership will be transferred.
QgsMergedFeatureRenderer(type: str, embeddedRenderer:
QgsFeatureRenderer
) Constructor for QgsMergedFeatureRenderer.- Parameters:
type – renderer ID string
embeddedRenderer –
optional embeddedRenderer. Ownership will be transferred.
Methods
- param visitor:
- rtype:
QgsFeatureRenderer.Capabilities
- param key:
- rtype:
QgsMergedFeatureRenderer
Creates a
QgsMergedFeatureRenderer
by a conversion from an existing renderer.Creates a renderer out of an XML, for loading
- rtype:
str
- rtype:
QgsFeatureRenderer
- rtype:
bool
- param feature:
- param key:
- rtype:
List[QgsLegendSymbolItem]
- rtype:
bool
- param feature:
- param feature:
Renders a given feature.
Render the
feature
with thesymbol
usingcontext
.render editing vertex marker at specified point
render editing vertex marker for a polygon
render editing vertex marker for a polyline
- param doc:
Saves generic renderer data into the specified
element
.- param subRenderer:
- param key:
- param context:
The actual rendering will take place here.
- param feature:
- param context:
- param feature:
- param context:
- param feature:
Attributes
- class GeometryOperation¶
Bases:
int
- InvertOnly = 1¶
- Merge = 0¶
- MergeAndInvert = 2¶
- accept(self, visitor: QgsStyleEntityVisitorInterface) bool ¶
- Parameters:
visitor (QgsStyleEntityVisitorInterface) –
- Return type:
bool
- capabilities(self) QgsFeatureRenderer.Capabilities ¶
- Return type:
- checkLegendSymbolItem(self, key: str, state: bool = True)¶
- Parameters:
key (str) –
state (bool = True) –
- clone(self) QgsMergedFeatureRenderer ¶
- Return type:
- convertFromRenderer(renderer: QgsFeatureRenderer) QgsMergedFeatureRenderer ¶
Creates a
QgsMergedFeatureRenderer
by a conversion from an existing renderer.- Return type:
- Returns:
a new renderer if the conversion was possible, otherwise
None
.- Parameters:
renderer (QgsFeatureRenderer) –
- convertSymbolRotation(symbol: QgsSymbol, field: str)¶
Note
this function is used to convert old rotations expressions to symbol level DataDefined angle
- convertSymbolSizeScale(symbol: QgsSymbol, method: Qgis.ScaleMethod, field: str)¶
Note
this function is used to convert old sizeScale expressions to symbol level DataDefined size
- create(element: QDomElement, context: QgsReadWriteContext) QgsFeatureRenderer ¶
Creates a renderer out of an XML, for loading
- Parameters:
element (QDomElement) –
context (QgsReadWriteContext) –
- Return type:
- dump(self) str ¶
- Return type:
str
- embeddedRenderer(self) QgsFeatureRenderer ¶
- Return type:
- filterNeedsGeometry(self) bool ¶
- Return type:
bool
- legendKeysForFeature(self, feature: QgsFeature, context: QgsRenderContext) Set[str] ¶
- Parameters:
feature (QgsFeature) –
context (QgsRenderContext) –
- Return type:
Set[str]
- legendSymbolItemChecked(self, key: str) bool ¶
- Parameters:
key (str) –
- Return type:
bool
- legendSymbolItems(self) List[QgsLegendSymbolItem] ¶
- Return type:
List[QgsLegendSymbolItem]
- legendSymbolItemsCheckable(self) bool ¶
- Return type:
bool
- originalSymbolForFeature(self, feature: QgsFeature, context: QgsRenderContext) QgsSymbol ¶
- Parameters:
feature (QgsFeature) –
context (QgsRenderContext) –
- Return type:
- originalSymbolsForFeature(self, feature: QgsFeature, context: QgsRenderContext) List[QgsSymbol] ¶
- Parameters:
feature (QgsFeature) –
context (QgsRenderContext) –
- Return type:
List[QgsSymbol]
- renderFeature(self, feature: QgsFeature, context: QgsRenderContext, layer: int = -1, selected: bool = False, drawVertexMarker: bool = False) bool ¶
Renders a given feature. This will here collect features. The actual rendering will be postponed to
stopRender()
- Parameters:
feature (QgsFeature) – the feature to render
context (QgsRenderContext) – the rendering context
layer (int = -1) – the symbol layer to render, if that makes sense
selected (bool = False) – whether this feature has been selected (this will add decorations)
drawVertexMarker (bool = False) – whether this feature has vertex markers (in edit mode usually)
- Return type:
bool
- Returns:
True
if the rendering was OK
- renderFeatureWithSymbol(self, feature: QgsFeature, symbol: QgsSymbol, context: QgsRenderContext, layer: int, selected: bool, drawVertexMarker: bool)¶
Render the
feature
with thesymbol
usingcontext
. Uselayer
to specify the symbol layer,selected
to specify if it should be rendered as selected anddrawVertexMarker
to specify if vertex markers should be rendered.
- renderVertexMarker(self, pt: QPointF | QPoint, context: QgsRenderContext)¶
render editing vertex marker at specified point
- renderVertexMarkerPolygon(self, pts: QPolygonF, rings: Iterable[QPolygonF], context: QgsRenderContext)¶
render editing vertex marker for a polygon
- renderVertexMarkerPolyline(self, pts: QPolygonF, context: QgsRenderContext)¶
render editing vertex marker for a polyline
- save(self, doc: QDomDocument, context: QgsReadWriteContext) QDomElement ¶
- Parameters:
doc (QDomDocument) –
context (QgsReadWriteContext) –
- Return type:
QDomElement
- saveRendererData(self, doc: QDomDocument, element: QDomElement, context: QgsReadWriteContext)¶
Saves generic renderer data into the specified
element
.This method should be called in a subclass’
save()
implementation in order to store all common base class properties in the DOMelement
.New in version 3.22.
- setEmbeddedRenderer(self, subRenderer: QgsFeatureRenderer)¶
- Parameters:
subRenderer (QgsFeatureRenderer) –
- setLegendSymbolItem(self, key: str, symbol: QgsSymbol)¶
- Parameters:
key (str) –
symbol (QgsSymbol) –
- startRender(self, context: QgsRenderContext, fields: QgsFields)¶
- Parameters:
context (QgsRenderContext) –
fields (QgsFields) –
- stopRender(self, context: QgsRenderContext)¶
The actual rendering will take place here. Features collected during
renderFeature()
are rendered using the embedded feature renderer- Parameters:
context (QgsRenderContext) –
- symbolForFeature(self, feature: QgsFeature, context: QgsRenderContext) QgsSymbol ¶
- Parameters:
feature (QgsFeature) –
context (QgsRenderContext) –
- Return type:
- symbols(self, context: QgsRenderContext) List[QgsSymbol] ¶
- Parameters:
context (QgsRenderContext) –
- Return type:
List[QgsSymbol]
- symbolsForFeature(self, feature: QgsFeature, context: QgsRenderContext) List[QgsSymbol] ¶
- Parameters:
feature (QgsFeature) –
context (QgsRenderContext) –
- Return type:
List[QgsSymbol]
- usedAttributes(self, context: QgsRenderContext) Set[str] ¶
- Parameters:
context (QgsRenderContext) –
- Return type:
Set[str]
- willRenderFeature(self, feature: QgsFeature, context: QgsRenderContext) bool ¶
- Parameters:
feature (QgsFeature) –
context (QgsRenderContext) –
- Return type:
bool