c++ helper class for defining QgsExpression functions. More...

#include <qgsexpression.h>

Inheritance diagram for QgsExpression::StaticFunction:

Public Member Functions
Q_DECL_DEPRECATED	StaticFunction (const QString &fnname, int params, FcnEval fcn, const QString &group, const QString &helpText=QString(), bool usesGeometry=false, const QStringList &referencedColumns=QStringList(), bool lazyEval=false, const QStringList &aliases=QStringList(), bool handlesNull=false)

	StaticFunction (const QString &fnname, int params, FcnEvalContext fcn, const QString &group, const QString &helpText=QString(), bool usesGeometry=false, const QStringList &referencedColumns=QStringList(), bool lazyEval=false, const QStringList &aliases=QStringList(), bool handlesNull=false)
	Static function for evaluation against a QgsExpressionContext. More...

virtual	~StaticFunction ()

virtual QStringList	aliases () const override
	Returns a list of possible aliases for the function. More...

virtual Q_DECL_DEPRECATED QVariant	func (const QVariantList &values, const QgsFeature f, QgsExpression parent) override

virtual QVariant	func (const QVariantList &values, const QgsExpressionContext context, QgsExpression parent) override
	Returns result of evaluating the function. More...

Public Member Functions inherited from QgsExpression::Function
	Function (const QString &fnname, int params, const QString &group, const QString &helpText=QString(), bool usesGeometry=false, const QStringList &referencedColumns=QStringList(), bool lazyEval=false, bool handlesNull=false, bool isContextual=false)

virtual	~Function ()

QString	group ()
	The group the function belongs to. More...

virtual bool	handlesNull () const

const QString	helptext ()
	The help text for the function. More...

bool	isContextual () const
	Returns whether the function is only available if provided by a QgsExpressionContext object. More...

bool	lazyEval ()
	True if this function should use lazy evaluation. More...

QString	name ()
	The name of the function. More...

bool	operator== (const Function &other) const

int	params ()
	The number of parameters this function takes. More...

virtual QStringList	referencedColumns () const

bool	usesgeometry ()
	Does this function use a geometry object. More...

Detailed Description

c++ helper class for defining QgsExpression functions.

Note: not available in Python bindings

Definition at line 531 of file qgsexpression.h.

Constructor & Destructor Documentation

Q_DECL_DEPRECATED QgsExpression::StaticFunction::StaticFunction	(	const QString &	fnname,
		int	params,
		FcnEval	fcn,
		const QString &	group,
		const QString &	helpText = `QString()`,
		bool	usesGeometry = `false`,
		const QStringList &	referencedColumns = `QStringList()`,
		bool	lazyEval = `false`,
		const QStringList &	aliases = `QStringList()`,
		bool	handlesNull = `false`
	)

inline

Deprecated:: use QgsExpressionContext variant instead

Definition at line 535 of file qgsexpression.h.

virtual QgsExpression::StaticFunction::~StaticFunction ( )

inlinevirtual

Definition at line 551 of file qgsexpression.h.

QgsExpression::StaticFunction::StaticFunction	(	const QString &	fnname,
		int	params,
		FcnEvalContext	fcn,
		const QString &	group,
		const QString &	helpText = `QString()`,
		bool	usesGeometry = `false`,
		const QStringList &	referencedColumns = `QStringList()`,
		bool	lazyEval = `false`,
		const QStringList &	aliases = `QStringList()`,
		bool	handlesNull = `false`
	)