QgsRelationReferenceFieldFormatter Class Reference

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

#include <qgsrelationreferencefieldformatter.h>

Inheritance diagram for QgsRelationReferenceFieldFormatter:

Public Member Functions
	QgsRelationReferenceFieldFormatter ()=default
	Default constructor of field formatter for a relation reference field. More...
QVariant	createCache (QgsVectorLayer *layer, int fieldIndex, const QVariantMap &config) const override
	Create a cache for a given field. More...
QString	id () const override
	Returns a unique id for this field formatter. More...
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. More...
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. More...
Public Member Functions inherited from QgsFieldFormatter
	QgsFieldFormatter ()=default
	Default constructor. More...
virtual	~QgsFieldFormatter ()=default
virtual Qt::AlignmentFlag	alignmentFlag (QgsVectorLayer *layer, int fieldIndex, const QVariantMap &config) const
	Returns the alignment for a particular field. 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 30 of file qgsrelationreferencefieldformatter.h.

Constructor & Destructor Documentation

QgsRelationReferenceFieldFormatter()

QgsRelationReferenceFieldFormatter::QgsRelationReferenceFieldFormatter ( )

default

Default constructor of field formatter for a relation reference field.

Member Function Documentation

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 97 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 26 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 31 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 92 of file qgsrelationreferencefieldformatter.cpp.

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

• /build/qgis-3.10.0+15buster/src/core/fieldformatter/qgsrelationreferencefieldformatter.h
• /build/qgis-3.10.0+15buster/src/core/fieldformatter/qgsrelationreferencefieldformatter.cpp