QGIS API Documentation
2.14.0-Essen
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c++ helper class for defining QgsExpression functions. More...
#include <qgsexpression.h>
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... | |
c++ helper class for defining QgsExpression functions.
Definition at line 531 of file qgsexpression.h.
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inline |
Definition at line 535 of file qgsexpression.h.
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inlinevirtual |
Definition at line 551 of file qgsexpression.h.
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inline |
Static function for evaluation against a QgsExpressionContext.
Definition at line 555 of file qgsexpression.h.
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inlineoverridevirtual |
Returns a list of possible aliases for the function.
These include other permissible names for the function, eg deprecated names.
Reimplemented from QgsExpression::Function.
Definition at line 585 of file qgsexpression.h.
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overridevirtual |
Reimplemented from QgsExpression::Function.
Definition at line 4732 of file qgsexpression.cpp.
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inlineoverridevirtual |
Returns result of evaluating the function.
values | list of values passed to the function |
context | context expression is being evaluated against |
parent | parent expression |
Reimplemented from QgsExpression::Function.
Definition at line 580 of file qgsexpression.h.