| QGIS API Documentation
    3.20.0-Odense (decaadbb31)
    | 
QgsPropertyTransformer subclass for transforming a numeric value into a color from a color ramp. More...
#include <qgspropertytransformer.h>

| Public Member Functions | |
| QgsColorRampTransformer (const QgsColorRampTransformer &other) | |
| Copy constructor.  More... | |
| QgsColorRampTransformer (double minValue=0.0, double maxValue=1.0, QgsColorRamp *ramp=nullptr, const QColor &nullColor=QColor(0, 0, 0, 0)) | |
| Constructor for QgsColorRampTransformer.  More... | |
| QgsColorRampTransformer * | clone () const override | 
| Returns a clone of the transformer.  More... | |
| QColor | color (double value) const | 
| Calculates the color corresponding to a specific value.  More... | |
| QgsColorRamp * | colorRamp () const | 
| Returns the color ramp used for calculating property colors.  More... | |
| bool | loadVariant (const QVariant &definition) override | 
| Loads this transformer from a QVariantMap, wrapped in a QVariant.  More... | |
| QColor | nullColor () const | 
| Returns the color corresponding to a null value.  More... | |
| QgsColorRampTransformer & | operator= (const QgsColorRampTransformer &other) | 
| QString | rampName () const | 
| Returns the color ramp's name.  More... | |
| void | setColorRamp (QgsColorRamp *ramp) | 
| Sets the color ramp to use for calculating property colors.  More... | |
| void | setNullColor (const QColor &color) | 
| Sets the color corresponding to a null value.  More... | |
| void | setRampName (const QString &name) | 
| Sets the color ramp's name.  More... | |
| QString | toExpression (const QString &baseExpression) const override | 
| Converts the transformer to a QGIS expression string.  More... | |
| QVariant | toVariant () const override | 
| Saves this transformer to a QVariantMap, wrapped in a QVariant.  More... | |
| QVariant | transform (const QgsExpressionContext &context, const QVariant &value) const override | 
| Calculates the transform of a value.  More... | |
| Type | transformerType () const override | 
| Returns the transformer type.  More... | |
|  Public Member Functions inherited from QgsPropertyTransformer | |
| QgsPropertyTransformer (const QgsPropertyTransformer &other) | |
| Copy constructor.  More... | |
| QgsPropertyTransformer (double minValue=0.0, double maxValue=1.0) | |
| Constructor for QgsPropertyTransformer.  More... | |
| virtual | ~QgsPropertyTransformer () | 
| QgsCurveTransform * | curveTransform () const | 
| Returns the curve transform applied to input values before they are transformed by the individual transform subclasses.  More... | |
| double | maxValue () const | 
| Returns the maximum value expected by the transformer.  More... | |
| double | minValue () const | 
| Returns the minimum value expected by the transformer.  More... | |
| QgsPropertyTransformer & | operator= (const QgsPropertyTransformer &other) | 
| void | setCurveTransform (QgsCurveTransform *transform) | 
| Sets a curve transform to apply to input values before they are transformed by the individual transform subclasses.  More... | |
| void | setMaxValue (double max) | 
| Sets the maximum value expected by the transformer.  More... | |
| void | setMinValue (double min) | 
| Sets the minimum value expected by the transformer.  More... | |
| Additional Inherited Members | |
|  Public Types inherited from QgsPropertyTransformer | |
| enum | Type { GenericNumericTransformer , SizeScaleTransformer , ColorRampTransformer } | 
| Transformer types.  More... | |
|  Static Public Member Functions inherited from QgsPropertyTransformer | |
| static QgsPropertyTransformer * | create (Type type) | 
| Factory method for creating a new property transformer of the specified type.  More... | |
| static QgsPropertyTransformer * | fromExpression (const QString &expression, QString &baseExpression, QString &fieldName) | 
| Attempts to parse an expression into a corresponding property transformer.  More... | |
|  Protected Member Functions inherited from QgsPropertyTransformer | |
| double | transformNumeric (double input) const | 
| Applies base class numeric transformations.  More... | |
|  Protected Attributes inherited from QgsPropertyTransformer | |
| std::unique_ptr< QgsCurveTransform > | mCurveTransform | 
| Optional curve transform.  More... | |
| double | mMaxValue | 
| Maximum value expected by the transformer.  More... | |
| double | mMinValue | 
| Minimum value expected by the transformer.  More... | |
QgsPropertyTransformer subclass for transforming a numeric value into a color from a color ramp.
Definition at line 608 of file qgspropertytransformer.h.
| QgsColorRampTransformer::QgsColorRampTransformer | ( | double | minValue = 0.0, | 
| double | maxValue = 1.0, | ||
| QgsColorRamp * | ramp = nullptr, | ||
| const QColor & | nullColor = QColor( 0, 0, 0, 0 ) | ||
| ) | 
Constructor for QgsColorRampTransformer.
| minValue | minimum expected value | 
| maxValue | maximum expected value | 
| ramp | source color ramp. Ownership is transferred to the transformer. | 
| nullColor | color to return for null values | 
Definition at line 525 of file qgspropertytransformer.cpp.
| QgsColorRampTransformer::QgsColorRampTransformer | ( | const QgsColorRampTransformer & | other | ) | 
Copy constructor.
Definition at line 535 of file qgspropertytransformer.cpp.
| 
 | overridevirtual | 
Returns a clone of the transformer.
Implements QgsPropertyTransformer.
Definition at line 555 of file qgspropertytransformer.cpp.
| QColor QgsColorRampTransformer::color | ( | double | value | ) | const | 
Calculates the color corresponding to a specific value.
| value | value to calculate color for | 
Definition at line 631 of file qgspropertytransformer.cpp.
| QgsColorRamp * QgsColorRampTransformer::colorRamp | ( | ) | const | 
Returns the color ramp used for calculating property colors.
Definition at line 642 of file qgspropertytransformer.cpp.
| 
 | overridevirtual | 
Loads this transformer from a QVariantMap, wrapped in a QVariant.
You can use QgsXmlUtils::readVariant to read it from an XML document.
Reimplemented from QgsPropertyTransformer.
Definition at line 580 of file qgspropertytransformer.cpp.
| 
 | inline | 
Returns the color corresponding to a null value.
Definition at line 661 of file qgspropertytransformer.h.
| QgsColorRampTransformer & QgsColorRampTransformer::operator= | ( | const QgsColorRampTransformer & | other | ) | 
Definition at line 544 of file qgspropertytransformer.cpp.
| 
 | inline | 
Returns the color ramp's name.
Definition at line 674 of file qgspropertytransformer.h.
| void QgsColorRampTransformer::setColorRamp | ( | QgsColorRamp * | ramp | ) | 
Sets the color ramp to use for calculating property colors.
| ramp | color ramp, ownership of ramp is transferred to the transformer. | 
Definition at line 647 of file qgspropertytransformer.cpp.
| 
 | inline | 
Sets the color corresponding to a null value.
| color | null color | 
Definition at line 668 of file qgspropertytransformer.h.
| 
 | inline | 
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.
Definition at line 682 of file qgspropertytransformer.h.
| 
 | overridevirtual | 
Converts the transformer to a QGIS expression string.
The baseExpression string consists of a sub-expression reflecting the parent property's state.
Implements QgsPropertyTransformer.
Definition at line 618 of file qgspropertytransformer.cpp.
| 
 | overridevirtual | 
Saves this transformer to a QVariantMap, wrapped in a QVariant.
You can use QgsXmlUtils::writeVariant to save it to an XML document.
Reimplemented from QgsPropertyTransformer.
Definition at line 566 of file qgspropertytransformer.cpp.
| 
 | overridevirtual | 
Calculates the transform of a value.
Derived classes must implement this to perform their transformations on input values
| context | expression context | 
| value | input value to transform | 
Implements QgsPropertyTransformer.
Definition at line 597 of file qgspropertytransformer.cpp.
| 
 | inlineoverridevirtual | 
Returns the transformer type.
Implements QgsPropertyTransformer.
Definition at line 629 of file qgspropertytransformer.h.