QgsProcessingParameterVectorLayer class

A vector layer (with or without geometry) parameter for processing algorithms.

Reference

Consider using the more versatile QgsProcessingParameterFeatureSource wherever possible.

Base classes

class QgsProcessingParameterDefinition: Base class for the definition of processing parameters.
class QgsProcessingParameterLimitedDataTypes: Can be inherited by parameters which require limits to their acceptable data types.

Public static functions

static auto fromScriptCode(const QString& name, const QString& description, bool isOptional, const QString& definition) -> QgsProcessingParameterVectorLayer*: Creates a new parameter using the definition from a script code.
static auto typeName() -> QString: Returns the type name for the parameter class.

Constructors, destructors, conversion operators

QgsProcessingParameterVectorLayer(const QString& name, const QString& description = QString(), const QList<int>& types = QList<int>(), const QVariant& defaultValue = QVariant(), bool optional = false): Constructor for QgsProcessingParameterVectorLayer.

Public functions

auto checkValueIsAcceptable(const QVariant& input, QgsProcessingContext* context = nullptr) const -> bool override: Checks whether the specified input value is acceptable for the parameter.
auto clone() const -> QgsProcessingParameterDefinition* override: Creates a clone of the parameter definition.
auto fromVariantMap(const QVariantMap& map) -> bool override: Restores this parameter to a QVariantMap.
auto toVariantMap() const -> QVariantMap override: Saves this parameter to a QVariantMap.
auto type() const -> QString override: Unique parameter type name.
auto valueAsPythonString(const QVariant& value, QgsProcessingContext& context) const -> QString override: Returns a string version of the parameter input value, which is suitable for use as an input parameter value when running an algorithm directly from a Python command.

Function documentation

bool QgsProcessingParameterVectorLayer::checkValueIsAcceptable(const QVariant& input, QgsProcessingContext* context = nullptr) const override

Checks whether the specified input value is acceptable for the parameter.

Returns true if the value can be accepted. The optional context parameter can be specified to allow a more stringent check to be performed, capable of checking for the presence of required layers and other factors within the context.

bool QgsProcessingParameterVectorLayer::fromVariantMap(const QVariantMap& map) override

Restores this parameter to a QVariantMap.

Subclasses should ensure that they call the base class method.

QVariantMap QgsProcessingParameterVectorLayer::toVariantMap() const override

Saves this parameter to a QVariantMap.

Subclasses should ensure that they call the base class method and then extend the result with additional properties.

QString QgsProcessingParameterVectorLayer::valueAsPythonString(const QVariant& value, QgsProcessingContext& context) const override

Returns a string version of the parameter input value, which is suitable for use as an input parameter value when running an algorithm directly from a Python command.

The returned value must be correctly escaped - e.g. string values must be wrapped in ' 's.