Field formatter for a relation reference field. More...

#include <qgsrelationreferencefieldformatter.h>

Inheritance diagram for QgsRelationReferenceFieldFormatter:

Public Member Functions
	QgsRelationReferenceFieldFormatter ()
	Default constructor of field formatter for a relation reference field.

QVariantList	availableValues (const QVariantMap &config, int countLimit, const QgsFieldFormatterContext &context) const override
	Returns a list of the values that would be possible to select with this widget type On a RelationReference that would be the parents ids or on ValueMap all the configured keys according to the settings in the config.

QVariant	createCache (QgsVectorLayer *layer, int fieldIndex, const QVariantMap &config) const override
	Create a cache for a given field.

QString	id () const override
	Returns a unique id for this field formatter.

QList< QgsVectorLayerRef >	layerDependencies (const QVariantMap &config) const override SIP_SKIP
	Returns a list of weak layer references to other layers required by this formatter for the given config.

QString	representValue (QgsVectorLayer *layer, int fieldIndex, const QVariantMap &config, const QVariant &cache, const QVariant &value) const override
	Create a pretty String representation of the value.

QVariant	sortValue (QgsVectorLayer *layer, int fieldIndex, const QVariantMap &config, const QVariant &cache, const QVariant &value) const override
	If the default sort order should be overwritten for this widget, you can transform the value in here.

Public Member Functions inherited from QgsFieldFormatter
	QgsFieldFormatter ()=default
	Default constructor.

virtual	~QgsFieldFormatter ()=default

virtual Qt::AlignmentFlag	alignmentFlag (QgsVectorLayer *layer, int fieldIndex, const QVariantMap &config) const
	Returns the alignment for a particular field.

Flags	flags () const
	Returns the flags.

void	setFlags (const Flags &flags)
	Sets the flags.

Additional Inherited Members
Public Types inherited from QgsFieldFormatter
enum	Flag { CanProvideAvailableValues = 1 }
	Flags for the abilities of the formatter. More...

Detailed Description

Field formatter for a relation reference field.

A value relation field formatter looks up the values from features on another layer.

Since: QGIS 3.0

Definition at line 31 of file qgsrelationreferencefieldformatter.h.

Constructor & Destructor Documentation

◆ QgsRelationReferenceFieldFormatter()

QgsRelationReferenceFieldFormatter::QgsRelationReferenceFieldFormatter ( )

Default constructor of field formatter for a relation reference field.

Definition at line 26 of file qgsrelationreferencefieldformatter.cpp.

Member Function Documentation

◆ availableValues()

QVariantList QgsRelationReferenceFieldFormatter::availableValues	(	const QVariantMap &	config,
		int	countLimit,
		const QgsFieldFormatterContext &	context
	)		const

overridevirtual

Returns a list of the values that would be possible to select with this widget type On a RelationReference that would be the parents ids or on ValueMap all the configured keys according to the settings in the config.

Since: QGIS 3.12

Reimplemented from QgsFieldFormatter.

Definition at line 197 of file qgsrelationreferencefieldformatter.cpp.

◆ createCache()

QVariant QgsRelationReferenceFieldFormatter::createCache	(	QgsVectorLayer *	layer,
		int	fieldIndex,
		const QVariantMap &	config
	)		const

overridevirtual

Create a cache for a given field.

This will be used in situations where a field is being represented various times in a loop. And will be passed to other methods on QgsFieldKit and QgsEditorWidgetWrapper.

For example, the attribute table will create a cache once for each field and then use this cache for representation. The QgsValueRelationFieldFormatter and QgsValueRelationEditorWidget implement this functionality to create a lookuptable once (a QVariantMap / dict) and are make use of a cache if present.

Since: QGIS 3.0

Reimplemented from QgsFieldFormatter.

Definition at line 106 of file qgsrelationreferencefieldformatter.cpp.

◆ id()

QString QgsRelationReferenceFieldFormatter::id ( ) const

overridevirtual

Returns a unique id for this field formatter.

This id will later be used to identify this field formatter in the registry with QgsFieldFormatterRegistry::fieldFormatter().

This id matches the id of a QgsEditorWidgetFactory.

Implements QgsFieldFormatter.

Definition at line 31 of file qgsrelationreferencefieldformatter.cpp.

◆ layerDependencies()

QList< QgsVectorLayerRef > QgsRelationReferenceFieldFormatter::layerDependencies ( const QVariantMap & config ) const

overridevirtual

Returns a list of weak layer references to other layers required by this formatter for the given config.

The default implementation returns an empty list.

This method should be reimplemented by formatters that handle relations with other layers, (e.g. ValueRelation) and can be used by client code to warn the user about missing required dependencies or to add some resolution logic in order to load the missing dependency.

Note: not available in Python bindings

Since: QGIS 3.12

Reimplemented from QgsFieldFormatter.

Definition at line 177 of file qgsrelationreferencefieldformatter.cpp.

◆ representValue()

QString QgsRelationReferenceFieldFormatter::representValue	(	QgsVectorLayer *	layer,
		int	fieldIndex,
		const QVariantMap &	config,
		const QVariant &	cache,
		const QVariant &	value
	)		const

overridevirtual

Create a pretty String representation of the value.

Returns: By default the string representation of the provided value as implied by the field definition is returned.

Since: QGIS 3.0

Reimplemented from QgsFieldFormatter.

Definition at line 36 of file qgsrelationreferencefieldformatter.cpp.

◆ sortValue()

QVariant QgsRelationReferenceFieldFormatter::sortValue	(	QgsVectorLayer *	layer,
		int	fieldIndex,
		const QVariantMap &	config,
		const QVariant &	cache,
		const QVariant &	value
	)		const

overridevirtual

If the default sort order should be overwritten for this widget, you can transform the value in here.

Returns: an unmodified value by default.

Since: QGIS 3.0

Reimplemented from QgsFieldFormatter.

Definition at line 101 of file qgsrelationreferencefieldformatter.cpp.

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

/build/qgis-3.34.0+99sid/src/core/fieldformatter/qgsrelationreferencefieldformatter.h
/build/qgis-3.34.0+99sid/src/core/fieldformatter/qgsrelationreferencefieldformatter.cpp

Public Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ QgsRelationReferenceFieldFormatter()

Member Function Documentation

◆ availableValues()

◆ createCache()

◆ id()

◆ layerDependencies()

◆ representValue()

◆ sortValue()