A field formatter helps to handle and display values for a field. More...

#include <qgsfieldformatter.h>

Inheritance diagram for QgsFieldFormatter:

[legend]

Public Types
enum	Flag { CanProvideAvailableValues = 1 }
	Flags for the abilities of the formatter. More...

Public Member Functions
	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...

virtual QVariantList	availableValues (const QVariantMap &config, int countLimit, const QgsFieldFormatterContext &context) const
	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. More...

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

Flags	flags () const
	Returns the flags. More...

virtual QString	id () const =0
	Returns a unique id for this field formatter. More...

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

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

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

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

Detailed Description

A field formatter helps to handle and display values for a field.

It allows for using a shared configuration with the editor widgets for representation of attribute values. Field kits normally have one single instance which is managed by the QgsFieldFormatterRegistry. Custom field formatters should be registered there and field formatters for use within code should normally be obtained from there.

This is an abstract base class and will always need to be subclassed.

Since: QGIS 3.0

Definition at line 72 of file qgsfieldformatter.h.

Member Enumeration Documentation

◆ Flag

enum QgsFieldFormatter::Flag

Flags for the abilities of the formatter.

Since: QGIS 3.12

Enumerator
CanProvideAvailableValues	Can provide possible values.

Definition at line 88 of file qgsfieldformatter.h.

Constructor & Destructor Documentation

◆ QgsFieldFormatter()

QgsFieldFormatter::QgsFieldFormatter ( )

default

Default constructor.

◆ ~QgsFieldFormatter()

virtual QgsFieldFormatter::~QgsFieldFormatter ( )

virtualdefault

Member Function Documentation

◆ alignmentFlag()

Qt::AlignmentFlag QgsFieldFormatter::alignmentFlag	(	QgsVectorLayer *	layer,
		int	fieldIndex,
		const QVariantMap &	config
	)		const

virtual

Returns the alignment for a particular field.

By default this will consider the field type but can be overwritten if mapped values are represented.

Since: QGIS 3.0

Definition at line 53 of file qgsfieldformatter.cpp.

◆ availableValues()

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

virtual

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 in QgsValueRelationFieldFormatter, QgsValueMapFieldFormatter, and QgsRelationReferenceFieldFormatter.

Definition at line 79 of file qgsfieldformatter.cpp.

◆ createCache()

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

virtual

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 in QgsValueRelationFieldFormatter, and QgsRelationReferenceFieldFormatter.

Definition at line 64 of file qgsfieldformatter.cpp.

◆ flags()

Flags QgsFieldFormatter::flags ( ) const

inline

Returns the flags.

Since: QGIS 3.12

Definition at line 170 of file qgsfieldformatter.h.

◆ id()

virtual QString QgsFieldFormatter::id ( ) const

pure virtual

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.

Implemented in QgsValueRelationFieldFormatter, QgsValueMapFieldFormatter, QgsRelationReferenceFieldFormatter, QgsRangeFieldFormatter, QgsListFieldFormatter, QgsKeyValueFieldFormatter, QgsFallbackFieldFormatter, QgsDateTimeFieldFormatter, and QgsCheckBoxFieldFormatter.

◆ layerDependencies()

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

virtual

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 in QgsValueRelationFieldFormatter, and QgsRelationReferenceFieldFormatter.

Definition at line 73 of file qgsfieldformatter.cpp.

◆ representValue()

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

virtual

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 in QgsValueRelationFieldFormatter, QgsValueMapFieldFormatter, QgsRelationReferenceFieldFormatter, QgsRangeFieldFormatter, QgsListFieldFormatter, QgsKeyValueFieldFormatter, QgsDateTimeFieldFormatter, and QgsCheckBoxFieldFormatter.

Definition at line 24 of file qgsfieldformatter.cpp.

◆ setFlags()

void QgsFieldFormatter::setFlags ( const Flags & flags )

Sets the flags.

Since: QGIS 3.12

Definition at line 88 of file qgsfieldformatter.cpp.

◆ sortValue()

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

virtual

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 in QgsValueRelationFieldFormatter, QgsValueMapFieldFormatter, and QgsRelationReferenceFieldFormatter.

Definition at line 43 of file qgsfieldformatter.cpp.

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

/build/qgis-3.16.0+99unstable/src/core/qgsfieldformatter.h
/build/qgis-3.16.0+99unstable/src/core/qgsfieldformatter.cpp

Public Types

Public Member Functions

Detailed Description

Member Enumeration Documentation

◆ Flag

Constructor & Destructor Documentation

◆ QgsFieldFormatter()

◆ ~QgsFieldFormatter()

Member Function Documentation

◆ alignmentFlag()

◆ availableValues()

◆ createCache()

◆ flags()

◆ id()

◆ layerDependencies()

◆ representValue()

◆ setFlags()

◆ sortValue()