Base class for the definition of processing parameters. More...

#include <qgsprocessingparameters.h>

Inheritance diagram for QgsProcessingParameterDefinition:

[legend]

Public Types
enum	Flag { FlagAdvanced = 1 << 1, FlagHidden = 1 << 2, FlagOptional = 1 << 3, FlagIsModelOutput = 1 << 4 }
	Parameter flags. More...

Public Member Functions
	QgsProcessingParameterDefinition (const QString &name, const QString &description=QString(), const QVariant &defaultValue=QVariant(), bool optional=false, const QString &help=QString())
	Constructor for QgsProcessingParameterDefinition. More...

virtual	~QgsProcessingParameterDefinition ()=default

QStringList	additionalExpressionContextVariables () const
	Returns a list of additional expression context variables which are available for use when evaluating this parameter. More...

QgsProcessingAlgorithm *	algorithm () const
	Returns a pointer to the algorithm which owns this parameter. More...

virtual QString	asPythonString (QgsProcessing::PythonOutputType outputType=QgsProcessing::PythonQgsProcessingAlgorithmSubclass) const
	Returns the parameter definition as a Python command which can be used within a Python Processing script. More...

virtual QString	asScriptCode () const
	Returns the parameter definition encoded in a string which can be used within a Processing script. More...

virtual bool	checkValueIsAcceptable (const QVariant &input, QgsProcessingContext *context=nullptr) const
	Checks whether the specified input value is acceptable for the parameter. More...

virtual QgsProcessingParameterDefinition *	clone () const =0
	Creates a clone of the parameter definition. More...

QVariant	defaultValue () const
	Returns the default value for the parameter. More...

virtual QStringList	dependsOnOtherParameters () const
	Returns a list of other parameter names on which this parameter is dependent (e.g. More...

QString	description () const
	Returns the description for the parameter. More...

QString	dynamicLayerParameterName () const
	Returns the name of the parameter for a layer linked to a dynamic parameter, or an empty string if this is not set. More...

QgsPropertyDefinition	dynamicPropertyDefinition () const
	Returns the property definition for dynamic properties. More...

Flags	flags () const
	Returns any flags associated with the parameter. More...

virtual bool	fromVariantMap (const QVariantMap &map)
	Restores this parameter to a QVariantMap. More...

QString	help () const
	Returns the help for the parameter. More...

virtual bool	isDestination () const
	Returns `true` if this parameter represents a file or layer destination, e.g. More...

bool	isDynamic () const
	Returns `true` if the parameter supports is dynamic, and can support data-defined values (i.e. More...

QVariantMap &	metadata ()
	Returns the parameter's freeform metadata. More...

QVariantMap	metadata () const
	Returns the parameter's freeform metadata. More...

QString	name () const
	Returns the name of the parameter. More...

QgsProcessingProvider *	provider () const
	Returns a pointer to the provider for the algorithm which owns this parameter. More...

void	setAdditionalExpressionContextVariables (const QStringList &variables)
	Sets a list of additional expression context variables which are available for use when evaluating this parameter. More...

void	setDefaultValue (const QVariant &value)
	Sets the default value for the parameter. More...

void	setDescription (const QString &description)
	Sets the description for the parameter. More...

void	setDynamicLayerParameterName (const QString &name)
	Sets the name for the parameter for a layer linked to a dynamic parameter, or an empty string if this is not set. More...

void	setDynamicPropertyDefinition (const QgsPropertyDefinition &definition)
	Sets the property definition for dynamic properties. More...

void	setFlags (Flags flags)
	Sets the flags associated with the parameter. More...

void	setHelp (const QString &help)
	Sets the help for the parameter. More...

void	setIsDynamic (bool dynamic)
	Sets whether the parameter is dynamic, and can support data-defined values (i.e. More...

void	setMetadata (const QVariantMap &metadata)
	Sets the parameter's freeform metadata. More...

void	setName (const QString &name)
	Sets the name of the parameter. More...

virtual QString	toolTip () const
	Returns a formatted tooltip for use with the parameter, which gives helpful information like parameter description, ID, and extra content like default values (depending on parameter type). More...

virtual QVariantMap	toVariantMap () const
	Saves this parameter to a QVariantMap. More...

virtual QString	type () const =0
	Unique parameter type name. More...

virtual QString	valueAsPythonString (const QVariant &value, QgsProcessingContext &context) const
	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. More...

Protected Attributes
QStringList	mAdditionalExpressionVariables
	Additional expression context variables exposed for use by this parameter. More...

QgsProcessingAlgorithm *	mAlgorithm = nullptr
	Pointer to algorithm which owns this parameter. More...

QVariant	mDefault
	Default value for parameter. More...

QString	mDescription
	Parameter description. More...

QString	mDynamicLayerParameterName
	Linked vector layer parameter name for dynamic properties. More...

Flags	mFlags
	Parameter flags. More...

QString	mHelp
	Parameter help. More...

bool	mIsDynamic = false
	True for dynamic parameters, which can have data-defined (QgsProperty) based values. More...

QVariantMap	mMetadata
	Freeform metadata for parameter. Mostly used by widget wrappers to customize their appearance and behavior. More...

QString	mName
	Parameter name. More...

QgsPropertyDefinition	mPropertyDefinition
	Data defined property definition. More...

Friends
class	QgsProcessingAlgorithm

Detailed Description

Base class for the definition of processing parameters.

Parameter definitions encapsulate properties regarding the behavior of parameters, their acceptable ranges, defaults, etc.

Since: QGIS 3.0

Definition at line 330 of file qgsprocessingparameters.h.

Member Enumeration Documentation

◆ Flag

enum QgsProcessingParameterDefinition::Flag

Parameter flags.

Enumerator
FlagAdvanced	Parameter is an advanced parameter which should be hidden from users by default.
FlagHidden	Parameter is hidden and should not be shown to users.
FlagOptional	Parameter is optional.
FlagIsModelOutput	Destination parameter is final output. The parameter name will be used.

Definition at line 421 of file qgsprocessingparameters.h.

Constructor & Destructor Documentation

◆ QgsProcessingParameterDefinition()

QgsProcessingParameterDefinition::QgsProcessingParameterDefinition	(	const QString &	name,
		const QString &	description = `QString()`,
		const QVariant &	defaultValue = `QVariant()`,
		bool	optional = `false`,
		const QString &	help = `QString()`
	)

Constructor for QgsProcessingParameterDefinition.

Definition at line 2292 of file qgsprocessingparameters.cpp.

◆ ~QgsProcessingParameterDefinition()

virtual QgsProcessingParameterDefinition::~QgsProcessingParameterDefinition ( )

virtualdefault

Member Function Documentation

◆ additionalExpressionContextVariables()

QStringList QgsProcessingParameterDefinition::additionalExpressionContextVariables ( ) const

inline

Returns a list of additional expression context variables which are available for use when evaluating this parameter.

The additional variables will be added to the variables exposed from the usual expression context available to the parameter. They can be used to expose variables which are ONLY available to this parameter.

The returned list should contain the variable names only, without the usual "@" prefix.

See also: setAdditionalExpressionContextVariables()

Since: QGIS 3.8

Definition at line 697 of file qgsprocessingparameters.h.

◆ algorithm()

QgsProcessingAlgorithm * QgsProcessingParameterDefinition::algorithm ( ) const

Returns a pointer to the algorithm which owns this parameter.

May be nullptr for non-owned parameters.

See also: provider()

Definition at line 2381 of file qgsprocessingparameters.cpp.

◆ asPythonString()

QString QgsProcessingParameterDefinition::asPythonString ( QgsProcessing::PythonOutputType outputType = QgsProcessing::PythonQgsProcessingAlgorithmSubclass ) const

virtual

Returns the parameter definition as a Python command which can be used within a Python Processing script.

The outputType argument specifies the desired output format for the Python string, i.e. the intended end use of the generated Python code.

Since: QGIS 3.6

Definition at line 2333 of file qgsprocessingparameters.cpp.

◆ asScriptCode()

QString QgsProcessingParameterDefinition::asScriptCode ( ) const

virtual

Returns the parameter definition encoded in a string which can be used within a Processing script.

Definition at line 2323 of file qgsprocessingparameters.cpp.

◆ checkValueIsAcceptable()

bool QgsProcessingParameterDefinition::checkValueIsAcceptable	(	const QVariant &	input,
		QgsProcessingContext *	context = `nullptr`
	)		const

virtual

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.

Definition at line 2300 of file qgsprocessingparameters.cpp.

◆ clone()

virtual QgsProcessingParameterDefinition* QgsProcessingParameterDefinition::clone ( ) const

pure virtual

Creates a clone of the parameter definition.

◆ defaultValue()

QVariant QgsProcessingParameterDefinition::defaultValue ( ) const

inline

Returns the default value for the parameter.

See also: setDefaultValue()

Definition at line 509 of file qgsprocessingparameters.h.

◆ dependsOnOtherParameters()

virtual QStringList QgsProcessingParameterDefinition::dependsOnOtherParameters ( ) const

inlinevirtual

Returns a list of other parameter names on which this parameter is dependent (e.g.

field parameters which depend on a parent layer parameter).

Reimplemented in QgsProcessingParameterDatabaseTable, QgsProcessingParameterDatabaseSchema, QgsProcessingParameterCoordinateOperation, QgsProcessingParameterLayoutItem, QgsProcessingParameterBand, QgsProcessingParameterField, QgsProcessingParameterExpression, QgsProcessingParameterDistance, QgsProcessingParameterFieldMapping, and QgsProcessingParameterAggregate.

Definition at line 602 of file qgsprocessingparameters.h.

◆ description()

QString QgsProcessingParameterDefinition::description ( ) const

inline

Returns the description for the parameter.

This is the user-visible string used to identify this parameter.

See also: setDescription()

Definition at line 474 of file qgsprocessingparameters.h.

◆ dynamicLayerParameterName()

QString QgsProcessingParameterDefinition::dynamicLayerParameterName ( ) const

inline

Returns the name of the parameter for a layer linked to a dynamic parameter, or an empty string if this is not set.

Dynamic parameters (see isDynamic()) can have an optional vector layer parameter linked to them, which indicates which layer the fields and values will be available from when evaluating the dynamic parameter.

See also: setDynamicLayerParameterName(); isDynamic(); dynamicPropertyDefinition()

Definition at line 669 of file qgsprocessingparameters.h.

◆ dynamicPropertyDefinition()

QgsPropertyDefinition QgsProcessingParameterDefinition::dynamicPropertyDefinition ( ) const

inline

Returns the property definition for dynamic properties.

See also: isDynamic(); setDynamicPropertyDefinition(); dynamicLayerParameterName()

Definition at line 648 of file qgsprocessingparameters.h.

◆ flags()

Flags QgsProcessingParameterDefinition::flags ( ) const

inline

Returns any flags associated with the parameter.

See also: setFlags()

Definition at line 522 of file qgsprocessingparameters.h.

◆ fromVariantMap()

bool QgsProcessingParameterDefinition::fromVariantMap ( const QVariantMap & map )

virtual

Restores this parameter to a QVariantMap.

Subclasses should ensure that they call the base class method.

See also: toVariantMap()

Definition at line 2370 of file qgsprocessingparameters.cpp.

◆ help()

QString QgsProcessingParameterDefinition::help ( ) const

inline

Returns the help for the parameter.

This is a descriptive (possibly lengthy), translated string explaining the parameter's behavior and use in depth.

See also: setHelp()

Since: QGIS 3.16

Definition at line 492 of file qgsprocessingparameters.h.

◆ isDestination()

virtual bool QgsProcessingParameterDefinition::isDestination ( ) const

inlinevirtual

Returns true if this parameter represents a file or layer destination, e.g.

parameters which are used for the destination for layers output by an algorithm will return true.

Reimplemented in QgsProcessingDestinationParameter.

Definition at line 453 of file qgsprocessingparameters.h.

◆ isDynamic()

bool QgsProcessingParameterDefinition::isDynamic ( ) const

inline

Returns true if the parameter supports is dynamic, and can support data-defined values (i.e.

QgsProperty based values).

See also: setIsDynamic(); dynamicPropertyDefinition(); dynamicLayerParameterName()

Definition at line 631 of file qgsprocessingparameters.h.

◆ metadata() [1/2]

QVariantMap& QgsProcessingParameterDefinition::metadata ( )

inline

Returns the parameter's freeform metadata.

This is mostly used by parameter widget wrappers in order to customize their appearance and behavior.

See also: setMetadata()

Definition at line 589 of file qgsprocessingparameters.h.

◆ metadata() [2/2]

QVariantMap QgsProcessingParameterDefinition::metadata ( ) const

inline

Returns the parameter's freeform metadata.

This is mostly used by parameter widget wrappers in order to customize their appearance and behavior.

See also: setMetadata()

Note: not available in Python bindings.

Definition at line 582 of file qgsprocessingparameters.h.

◆ name()

QString QgsProcessingParameterDefinition::name ( ) const

inline

Returns the name of the parameter.

This is the internal identifier by which algorithms access this parameter.

See also: setName()

Definition at line 460 of file qgsprocessingparameters.h.

◆ provider()

QgsProcessingProvider * QgsProcessingParameterDefinition::provider ( ) const

Returns a pointer to the provider for the algorithm which owns this parameter.

May be nullptr for non-owned parameters or algorithms.

See also: algorithm()

Definition at line 2386 of file qgsprocessingparameters.cpp.

◆ setAdditionalExpressionContextVariables()

void QgsProcessingParameterDefinition::setAdditionalExpressionContextVariables ( const QStringList & variables )

inline

Sets a list of additional expression context variables which are available for use when evaluating this parameter.

The additional variables will be added to the variables exposed from the usual expression context available to the parameter. They can be used to expose variables which are ONLY available to this parameter.

The variables list should contain the variable names only, without the usual "@" prefix.

Note: Specifying variables via this method is for metadata purposes only. It is the algorithm's responsibility to correctly set the value of these additional variables in all expression context used when evaluating the parameter, in whichever way is appropriate for that particular variable.

See also: additionalExpressionContextVariables()

Since: QGIS 3.8

Definition at line 716 of file qgsprocessingparameters.h.

◆ setDefaultValue()

void QgsProcessingParameterDefinition::setDefaultValue ( const QVariant & value )

inline

Sets the default value for the parameter.

Caller takes responsibility to ensure that value is a valid input for the parameter subclass.

See also: defaultValue()

Definition at line 516 of file qgsprocessingparameters.h.

◆ setDescription()

void QgsProcessingParameterDefinition::setDescription ( const QString & description )

inline

Sets the description for the parameter.

This is the user-visible string used to identify this parameter.

See also: description()

Definition at line 481 of file qgsprocessingparameters.h.

◆ setDynamicLayerParameterName()

void QgsProcessingParameterDefinition::setDynamicLayerParameterName ( const QString & name )

inline

Sets the name for the parameter for a layer linked to a dynamic parameter, or an empty string if this is not set.

Dynamic parameters (see isDynamic()) can have an optional vector layer parameter linked to them, which indicates which layer the fields and values will be available from when evaluating the dynamic parameter.

See also: dynamicLayerParameterName(); isDynamic(); setDynamicPropertyDefinition()

Definition at line 682 of file qgsprocessingparameters.h.

◆ setDynamicPropertyDefinition()

void QgsProcessingParameterDefinition::setDynamicPropertyDefinition ( const QgsPropertyDefinition & definition )

inline

Sets the property definition for dynamic properties.

See also: isDynamic(); dynamicPropertyDefinition(); setDynamicLayerParameterName()

Definition at line 656 of file qgsprocessingparameters.h.

◆ setFlags()

void QgsProcessingParameterDefinition::setFlags ( Flags flags )

inline

Sets the flags associated with the parameter.

See also: flags()

Definition at line 528 of file qgsprocessingparameters.h.

◆ setHelp()

void QgsProcessingParameterDefinition::setHelp ( const QString & help )

inline

Sets the help for the parameter.

The help string should be a descriptive, translated string explaining the parameter's behavior and use in depth.

See also: help()

Since: QGIS 3.16

Definition at line 503 of file qgsprocessingparameters.h.

◆ setIsDynamic()

void QgsProcessingParameterDefinition::setIsDynamic ( bool dynamic )

inline

Sets whether the parameter is dynamic, and can support data-defined values (i.e.

QgsProperty based values).

See also: isDynamic(); setDynamicPropertyDefinition(); setDynamicLayerParameterName()

Definition at line 640 of file qgsprocessingparameters.h.

◆ setMetadata()

void QgsProcessingParameterDefinition::setMetadata ( const QVariantMap & metadata )

inline

Sets the parameter's freeform metadata.

This is mostly used by parameter widget wrappers in order to customize their appearance and behavior.

See also: metadata()

Definition at line 596 of file qgsprocessingparameters.h.

◆ setName()

void QgsProcessingParameterDefinition::setName ( const QString & name )

inline

Sets the name of the parameter.

This is the internal identifier by which algorithms access this parameter.

See also: name()

Definition at line 467 of file qgsprocessingparameters.h.

◆ toolTip()

QString QgsProcessingParameterDefinition::toolTip ( ) const

virtual

Returns a formatted tooltip for use with the parameter, which gives helpful information like parameter description, ID, and extra content like default values (depending on parameter type).

Reimplemented in QgsProcessingParameterDateTime, and QgsProcessingParameterNumber.

Definition at line 2391 of file qgsprocessingparameters.cpp.

◆ toVariantMap()

QVariantMap QgsProcessingParameterDefinition::toVariantMap ( ) const

virtual

Saves this parameter to a QVariantMap.

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

See also: fromVariantMap()

Definition at line 2357 of file qgsprocessingparameters.cpp.

◆ type()

virtual QString QgsProcessingParameterDefinition::type ( ) const

pure virtual

Unique parameter type name.

◆ valueAsPythonString()

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

virtual

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.

Definition at line 2312 of file qgsprocessingparameters.cpp.

Friends And Related Function Documentation

◆ QgsProcessingAlgorithm

friend class QgsProcessingAlgorithm

friend

Definition at line 754 of file qgsprocessingparameters.h.

Member Data Documentation

◆ mAdditionalExpressionVariables

QStringList QgsProcessingParameterDefinition::mAdditionalExpressionVariables

protected

Additional expression context variables exposed for use by this parameter.

Definition at line 751 of file qgsprocessingparameters.h.

◆ mAlgorithm

QgsProcessingAlgorithm* QgsProcessingParameterDefinition::mAlgorithm = nullptr

protected

Pointer to algorithm which owns this parameter.

Definition at line 739 of file qgsprocessingparameters.h.

◆ mDefault

QVariant QgsProcessingParameterDefinition::mDefault

protected

Default value for parameter.

Definition at line 730 of file qgsprocessingparameters.h.

◆ mDescription

QString QgsProcessingParameterDefinition::mDescription

protected

Parameter description.

Definition at line 724 of file qgsprocessingparameters.h.

◆ mDynamicLayerParameterName

QString QgsProcessingParameterDefinition::mDynamicLayerParameterName

protected

Linked vector layer parameter name for dynamic properties.

Definition at line 748 of file qgsprocessingparameters.h.

◆ mFlags

Flags QgsProcessingParameterDefinition::mFlags

protected

Parameter flags.

Definition at line 733 of file qgsprocessingparameters.h.

◆ mHelp

QString QgsProcessingParameterDefinition::mHelp

protected

Parameter help.

Definition at line 727 of file qgsprocessingparameters.h.

◆ mIsDynamic

bool QgsProcessingParameterDefinition::mIsDynamic = false

protected

True for dynamic parameters, which can have data-defined (QgsProperty) based values.

Definition at line 742 of file qgsprocessingparameters.h.

◆ mMetadata

QVariantMap QgsProcessingParameterDefinition::mMetadata

protected

Freeform metadata for parameter. Mostly used by widget wrappers to customize their appearance and behavior.

Definition at line 736 of file qgsprocessingparameters.h.

◆ mName

QString QgsProcessingParameterDefinition::mName

protected

Parameter name.

Definition at line 721 of file qgsprocessingparameters.h.

◆ mPropertyDefinition

QgsPropertyDefinition QgsProcessingParameterDefinition::mPropertyDefinition

protected

Data defined property definition.

Definition at line 745 of file qgsprocessingparameters.h.

The documentation for this class was generated from the following files:

/build/qgis-3.16.0+99unstable/src/core/processing/qgsprocessingparameters.h
/build/qgis-3.16.0+99unstable/src/core/processing/qgsprocessingparameters.cpp

Public Types

Public Member Functions

Protected Attributes

Friends

Detailed Description

Member Enumeration Documentation

◆ Flag

Constructor & Destructor Documentation

◆ QgsProcessingParameterDefinition()

◆ ~QgsProcessingParameterDefinition()

Member Function Documentation

◆ additionalExpressionContextVariables()

◆ algorithm()

◆ asPythonString()

◆ asScriptCode()

◆ checkValueIsAcceptable()

◆ clone()

◆ defaultValue()

◆ dependsOnOtherParameters()

◆ description()

◆ dynamicLayerParameterName()

◆ dynamicPropertyDefinition()

◆ flags()

◆ fromVariantMap()

◆ help()

◆ isDestination()

◆ isDynamic()

◆ metadata() [1/2]

◆ metadata() [2/2]

◆ name()

◆ provider()

◆ setAdditionalExpressionContextVariables()

◆ setDefaultValue()

◆ setDescription()

◆ setDynamicLayerParameterName()

◆ setDynamicPropertyDefinition()

◆ setFlags()

◆ setHelp()

◆ setIsDynamic()

◆ setMetadata()

◆ setName()

◆ toolTip()

◆ toVariantMap()

◆ type()

◆ valueAsPythonString()

Friends And Related Function Documentation

◆ QgsProcessingAlgorithm

Member Data Documentation

◆ mAdditionalExpressionVariables

◆ mAlgorithm

◆ mDefault

◆ mDescription

◆ mDynamicLayerParameterName

◆ mFlags

◆ mHelp

◆ mIsDynamic

◆ mMetadata

◆ mName

◆ mPropertyDefinition