Stores information about constraints which may be present on a field. More...

#include <qgsfieldconstraints.h>

Public Types
enum	Constraint { ConstraintNotNull = 1, ConstraintUnique = 1 << 1, ConstraintExpression = 1 << 2 }
	Constraints which may be present on a field. More...

enum	ConstraintOrigin { ConstraintOriginNotSet = 0, ConstraintOriginProvider, ConstraintOriginLayer }
	Origin of constraints. More...

enum	ConstraintStrength { ConstraintStrengthNotSet = 0, ConstraintStrengthHard, ConstraintStrengthSoft }
	Strength of constraints. More...

Public Member Functions
	QgsFieldConstraints ()
	Constructor for QgsFieldConstraints. More...

QString	constraintDescription () const
	Returns the descriptive name for the constraint expression. More...

QString	constraintExpression () const
	Returns the constraint expression for the field, if set. More...

ConstraintOrigin	constraintOrigin (Constraint constraint) const
	Returns the origin of a field constraint, or ConstraintOriginNotSet if the constraint is not present on this field. More...

Constraints	constraints () const
	Returns any constraints which are present for the field. More...

ConstraintStrength	constraintStrength (Constraint constraint) const
	Returns the strength of a field constraint, or ConstraintStrengthNotSet if the constraint is not present on this field. More...

bool	operator== (const QgsFieldConstraints &other) const

void	removeConstraint (Constraint constraint)
	Removes a constraint from the field. More...

void	setConstraint (Constraint constraint, ConstraintOrigin origin=ConstraintOriginLayer)
	Sets a constraint on the field. More...

void	setConstraintExpression (const QString &expression, const QString &description=QString())
	Set the constraint expression for the field. More...

void	setConstraintStrength (Constraint constraint, ConstraintStrength strength)
	Sets the strength of a constraint. More...

Properties
Constraints	constraints

Detailed Description

Stores information about constraints which may be present on a field.

Since: QGIS 3.0

Definition at line 32 of file qgsfieldconstraints.h.

Member Enumeration Documentation

◆ Constraint

enum QgsFieldConstraints::Constraint

Constraints which may be present on a field.

Enumerator
ConstraintNotNull	Field may not be null.
ConstraintUnique	Field must have a unique value.
ConstraintExpression	Field has an expression constraint set. See constraintExpression().

Definition at line 43 of file qgsfieldconstraints.h.

◆ ConstraintOrigin

enum QgsFieldConstraints::ConstraintOrigin

Origin of constraints.

Enumerator
ConstraintOriginNotSet	Constraint is not set.
ConstraintOriginProvider	Constraint was set at data provider.
ConstraintOriginLayer	Constraint was set by layer.

Definition at line 54 of file qgsfieldconstraints.h.

◆ ConstraintStrength

enum QgsFieldConstraints::ConstraintStrength

Strength of constraints.

Enumerator
ConstraintStrengthNotSet	Constraint is not set.
ConstraintStrengthHard	Constraint must be honored before feature can be accepted.
ConstraintStrengthSoft	User is warned if constraint is violated but feature can still be accepted.

Definition at line 64 of file qgsfieldconstraints.h.

Constructor & Destructor Documentation

◆ QgsFieldConstraints()

QgsFieldConstraints::QgsFieldConstraints ( )

default

Constructor for QgsFieldConstraints.

Member Function Documentation

◆ constraintDescription()

QString QgsFieldConstraints::constraintDescription ( ) const

inline

Returns the descriptive name for the constraint expression.

See also: constraints(); constraintExpression(); setConstraintExpression()

Definition at line 134 of file qgsfieldconstraints.h.

◆ constraintExpression()

QString QgsFieldConstraints::constraintExpression ( ) const

Returns the constraint expression for the field, if set.

See also: constraints(); constraintDescription(); setConstraintExpression()

Definition at line 72 of file qgsfieldconstraints.cpp.

◆ constraintOrigin()

QgsFieldConstraints::ConstraintOrigin QgsFieldConstraints::constraintOrigin ( QgsFieldConstraints::Constraint constraint ) const

Returns the origin of a field constraint, or ConstraintOriginNotSet if the constraint is not present on this field.

See also: constraints()

Definition at line 19 of file qgsfieldconstraints.cpp.

◆ constraints()

Constraints QgsFieldConstraints::constraints ( ) const

inline

Returns any constraints which are present for the field.

See also: setConstraint(); constraintOrigin()

Definition at line 81 of file qgsfieldconstraints.h.

◆ constraintStrength()

QgsFieldConstraints::ConstraintStrength QgsFieldConstraints::constraintStrength ( QgsFieldConstraints::Constraint constraint ) const

Returns the strength of a field constraint, or ConstraintStrengthNotSet if the constraint is not present on this field.

See also: constraints(); setConstraintStrength()

Definition at line 27 of file qgsfieldconstraints.cpp.

◆ operator==()

bool QgsFieldConstraints::operator== ( const QgsFieldConstraints & other ) const

Definition at line 91 of file qgsfieldconstraints.cpp.

◆ removeConstraint()

void QgsFieldConstraints::removeConstraint ( Constraint constraint )

inline

Removes a constraint from the field.

See also: setConstraint(); constraints()

Definition at line 118 of file qgsfieldconstraints.h.

◆ setConstraint()

void QgsFieldConstraints::setConstraint	(	QgsFieldConstraints::Constraint	constraint,
		QgsFieldConstraints::ConstraintOrigin	origin = `ConstraintOriginLayer`
	)

Sets a constraint on the field.

See also: constraints(); removeConstraint()

Definition at line 53 of file qgsfieldconstraints.cpp.

◆ setConstraintExpression()

void QgsFieldConstraints::setConstraintExpression	(	const QString &	expression,
		const QString &	description = `QString()`
	)

Set the constraint expression for the field.

An optional descriptive name for the constraint can also be set. Setting an empty expression will clear any existing expression constraint.

See also: constraintExpression(); constraintDescription(); constraints()

Definition at line 77 of file qgsfieldconstraints.cpp.

◆ setConstraintStrength()

void QgsFieldConstraints::setConstraintStrength	(	QgsFieldConstraints::Constraint	constraint,
		QgsFieldConstraints::ConstraintStrength	strength
	)

Sets the strength of a constraint.

Note that the strength of constraints which originate from a provider cannot be changed. Constraints default to ConstraintStrengthHard unless explicitly changed.

See also: constraintStrength()

Definition at line 36 of file qgsfieldconstraints.cpp.

Property Documentation

◆ constraints

Constraints QgsFieldConstraints::constraints

read

Definition at line 36 of file qgsfieldconstraints.h.

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

/tmp/buildd/qgis-3.6.0+99unstable/src/core/qgsfieldconstraints.h
/tmp/buildd/qgis-3.6.0+99unstable/src/core/qgsfieldconstraints.cpp

Public Types

Public Member Functions

Properties

Detailed Description

Member Enumeration Documentation

◆ Constraint

◆ ConstraintOrigin

◆ ConstraintStrength

Constructor & Destructor Documentation

◆ QgsFieldConstraints()

Member Function Documentation

◆ constraintDescription()

◆ constraintExpression()

◆ constraintOrigin()

◆ constraints()

◆ constraintStrength()

◆ operator==()

◆ removeConstraint()

◆ setConstraint()

◆ setConstraintExpression()

◆ setConstraintStrength()

Property Documentation

◆ constraints