def apply_style(layer, style, is_new, name):
"""Apply the style to a new or existing layer
:param layer: QGIS layer instance
:type layer: QgsVectorLayer
:param style: optional, dictionary with style properties: example {'color': [100, 50, 123], 'transparency': 0.5, 'stroke_width: 3 }
:type style: dict
:param is_new: True is the layer is a new layer
:type is_new: bool
:param name: name of the isochrone, if blank/None create a timestamp for the name if the layer is not new
:type name: str
"""
if style is None:
return
def _set_labeling():
pal_layer = QgsPalLayerSettings()
pal_layer.fieldName = 'value'
pal_layer.enabled = True
pal_layer.placementFlags = QgsLabeling.OnLine
pal_layer.placement = QgsPalLayerSettings.PerimeterCurved
text_format = pal_layer.format()
buffer = text_format.buffer()
buffer.setColor(QColor(255, 255, 255))
buffer.setOpacity(0.5)
buffer.setEnabled(True)
text_format.setBuffer(buffer)
pal_layer.setFormat(text_format)
labels = QgsVectorLayerSimpleLabeling(pal_layer)
return labels
def _set_rule(renderer):
root_rule = renderer.rootRule()
if is_new:
rule = root_rule.children()[0]
else:
rule = root_rule.children()[0].clone()
rule.setLabel(name)
expression = '"name" = {}'.format(QgsExpression.quotedString(name))
rule.setFilterExpression(expression)
rule.symbol().setColor(QColor(*style['color'], 255))
rule.symbol().setOpacity(1 - style['transparency'])
rule.symbol().symbolLayers()[0].setStrokeWidth(style['stroke_width'])
rule.symbol().symbolLayers()[0].setStrokeColor(QColor(255, 255, 255))
if not is_new:
root_rule.appendChild(rule)
if is_new: # Create the new style
symbol = QgsSymbol.defaultSymbol(layer.geometryType())
renderer = QgsRuleBasedRenderer(symbol)
req = QgsFeatureRequest()
req.addOrderBy('"value"', False, False)
renderer.setOrderBy(req.orderBy())
renderer.setOrderByEnabled(True)
_set_rule(renderer)
# Delete first rule
layer.setRenderer(renderer)
labels = _set_labeling()
layer.setLabeling(labels)
layer.setCustomProperty("labeling/bufferDraw", True)
layer.setLabelsEnabled(True)
else:
# Check for rule based renderer, pass if not present
renderer = layer.renderer()
if isinstance(renderer, QgsRuleBasedRenderer):
_set_rule(renderer)
