Class: QgsColorRampTransformer¶
-
class
qgis.core.
QgsColorRampTransformer
(minValue: float = 0, maxValue: float = 1, ramp: QgsColorRamp = None, nullColor: Union[QColor, Qt.GlobalColor, QGradient] = QColor(0, 0, 0, 0))¶ Bases:
QgsPropertyTransformer
Constructor for QgsColorRampTransformer.
- Parameters
minValue (float = 0) – minimum expected value
maxValue (float = 1) – maximum expected value
ramp (
QgsColorRamp
= None) – source color ramp. Ownership is transferred to the transformer.nullColor (Union[QColor) – color to return for null values
QgsColorRampTransformer(other:
QgsColorRampTransformer
) Copy constructorQgsPropertyTransformer
subclass for transforming a numeric value into a color from a color ramp.Methods
- rtype
QgsColorRampTransformer
Calculates the color corresponding to a specific value.
Returns the color ramp used for calculating property colors.
- param definition
Returns the color corresponding to a null value.
Returns the color ramp’s name.
Sets the color ramp to use for calculating property colors.
Sets the color corresponding to a null value.
Sets the color ramp’s
name
.- param baseExpression
- rtype
Any
- param context
- rtype
QgsPropertyTransformer.Type
-
clone
(self) → QgsColorRampTransformer¶ - Return type
-
color
(self, value: float) → QColor¶ Calculates the color corresponding to a specific value.
- Parameters
value (float) – value to calculate color for
- Return type
QColor
- Returns
calculated color using transformer’s parameters and type
-
colorRamp
(self) → QgsColorRamp¶ Returns the color ramp used for calculating property colors.
- Return type
- Returns
color ramp
See also
-
loadVariant
(self, definition: Any) → bool¶ - Parameters
definition (Any) –
- Return type
bool
-
nullColor
(self) → QColor¶ Returns the color corresponding to a null value.
See also
- Return type
QColor
-
rampName
(self) → str¶ Returns the color ramp’s name.
See also
- Return type
str
-
setColorRamp
(self, ramp: QgsColorRamp)¶ Sets the color ramp to use for calculating property colors.
- Parameters
ramp (QgsColorRamp) – color ramp, ownership of ramp is transferred to the transformer.
See also
-
setNullColor
(self, color: Union[QColor, Qt.GlobalColor, QGradient])¶ Sets the color corresponding to a null value.
- Parameters
color (Union[QColor) – null color
See also
-
setRampName
(self, name: str)¶ Sets the color ramp’s
name
. The ramp name must be set to match a color ramp available in the style database for conversion to expression to work correctly.See also
- Parameters
name (str) –
-
toExpression
(self, baseExpression: str) → str¶ - Parameters
baseExpression (str) –
- Return type
str
-
toVariant
(self) → Any¶ - Return type
Any
-
transform
(self, context: QgsExpressionContext, value: Any) → Any¶ - Parameters
context (QgsExpressionContext) –
value (Any) –
- Return type
Any
-
transformNumeric
()¶
-
transformerType
(self) → QgsPropertyTransformer.Type¶ - Return type