Wraps a value relation widget. More...

#include <qgsvaluerelationwidgetwrapper.h>

Inheritance diagram for QgsValueRelationWidgetWrapper:

[legend]

Public Slots
void	parentFormValueChanged (const QString &attribute, const QVariant &value) override

Public Slots inherited from QgsEditorWidgetWrapper
void	emitValueChanged ()
	Will call the value() method to determine the emitted value.

virtual void	parentFormValueChanged (const QString &attribute, const QVariant &value)
	Is called in embedded form widgets when an attribute value in the parent form has changed.

void	setFeature (const QgsFeature &feature) override
	Will be called when the feature changes.

virtual void	setValue (const QVariant &value)
	Is called when the value of the widget needs to be changed.

void	setValues (const QVariant &value, const QVariantList &additionalValues)
	Is called when the value of the widget or additional field values needs to be changed.

Public Slots inherited from QgsWidgetWrapper

Public Member Functions
	QgsValueRelationWidgetWrapper (QgsVectorLayer layer, int fieldIdx, QWidget editor=nullptr, QWidget *parent=nullptr)
	Constructor for QgsValueRelationWidgetWrapper.

void	setEnabled (bool enabled) override
	Is used to enable or disable the edit functionality of the managed widget.

void	showIndeterminateState () override
	Sets the widget to display in an indeterminate "mixed value" state.

QVariant	value () const override
	Will be used to access the widget's value.

Public Member Functions inherited from QgsEditorWidgetWrapper
	QgsEditorWidgetWrapper (QgsVectorLayer vl, int fieldIdx, QWidget editor=nullptr, QWidget *parent=nullptr)
	Create a new widget wrapper.

virtual QStringList	additionalFields () const
	Returns the list of additional fields which the editor handles.

virtual QVariantList	additionalFieldValues () const
	Will be used to access the widget's values for potential additional fields handled by the widget.

QString	constraintFailureReason () const
	Returns the reason why a constraint check has failed (or an empty string if constraint check was successful).

ConstraintResult	constraintResult () const
	Returns the constraint result, which is the current result of the constraint on the widget influencing its visualization.

bool	constraintResultVisible () const
	Returns whether the constraint result is visible.

QVariant	defaultValue () const
	Access the default value of the field.

QgsField	field () const
	Access the field.

int	fieldIdx () const
	Access the field index.

bool	isBlockingCommit () const
	Returns `true` if the widget is preventing the feature from being committed.

bool	isValidConstraint () const
	Gets the current constraint status.

void	setConstraintResultVisible (bool constraintResultVisible)
	Sets whether the constraint result is visible.

virtual void	setHint (const QString &hintText)
	Add a hint text on the widget.

void	updateConstraint (const QgsFeature &featureContext, QgsFieldConstraints::ConstraintOrigin constraintOrigin=QgsFieldConstraints::ConstraintOriginNotSet)
	Update constraint.

void	updateConstraint (const QgsVectorLayer *layer, int index, const QgsFeature &feature, QgsFieldConstraints::ConstraintOrigin constraintOrigin=QgsFieldConstraints::ConstraintOriginNotSet)
	Update constraint on a feature coming from a specific layer.

void	updateConstraint (QgsEditorWidgetWrapper::ConstraintResult constraintResult, const QString &constraintFailureReason)
	Update constraint manually by providing the constraint result value and failure reason(s).

Public Member Functions inherited from QgsWidgetWrapper
	QgsWidgetWrapper (QgsVectorLayer vl, QWidget editor=nullptr, QWidget *parent=nullptr)
	Create a new widget wrapper.

QVariantMap	config () const
	Returns the whole config.

QVariant	config (const QString &key, const QVariant &defaultVal=QVariant()) const
	Use this inside your overridden classes to access the configuration.

const QgsAttributeEditorContext &	context () const
	Returns information about the context in which this widget is shown.

QgsPropertyCollection &	dataDefinedProperties ()
	Returns a reference to the editor widget's property collection, used for data defined overrides.

const QgsPropertyCollection &	dataDefinedProperties () const
	Returns a reference to the editor widget's property collection, used for data defined overrides.

QgsVectorLayer *	layer () const
	Returns the vector layer associated with the widget.

void	notifyAboutToSave ()
	Notify this widget, that the containing form is about to save and that any pending changes should be pushed to the edit buffer or they might be lost.

void	setConfig (const QVariantMap &config)
	Will set the config of this wrapper to the specified config.

void	setContext (const QgsAttributeEditorContext &context)
	Set the context in which this widget is shown.

void	setDataDefinedProperties (const QgsPropertyCollection &collection)
	Sets the editor widget's property collection, used for data defined overrides.

QWidget *	widget ()
	Access the widget managed by this wrapper.

template<class T >
T *	widget ()
	Access the widget managed by this wrapper and cast it to a given type.

Protected Member Functions
QWidget *	createWidget (QWidget *parent) override
	This method should create a new widget with the provided parent.

void	initWidget (QWidget *editor) override
	This method should initialize the editor widget with runtime data.

void	setFeature (const QgsFeature &feature) override
	Will be called when the feature changes.

bool	valid () const override
	Returns `true` if the widget has been properly initialized.

void	widgetValueChanged (const QString &attribute, const QVariant &newValue, bool attributeChanged)
	Will be called when a value in the current edited form or table row changes.

Protected Member Functions inherited from QgsEditorWidgetWrapper
QgsFeature	formFeature () const
	The feature currently being edited, in its current state.

void	setFormFeature (const QgsFeature &feature)
	Set the feature currently being edited to feature.

bool	setFormFeatureAttribute (const QString &attributeName, const QVariant &attributeValue)
	Update the feature currently being edited by changing its attribute attributeName to attributeValue.

virtual void	updateConstraintWidgetStatus ()
	This should update the widget with a visual cue if a constraint status changed.

Friends
class	QgsValueRelationWidgetFactory

class	TestQgsValueRelationWidgetWrapper

Additional Inherited Members
Public Types inherited from QgsEditorWidgetWrapper
enum	ConstraintResult { ConstraintResultPass = 0 , ConstraintResultFailHard , ConstraintResultFailSoft }
	Result of constraint checks. More...

Public Types inherited from QgsWidgetWrapper
enum class	Property : int { RootPath = 0 , DocumentViewerContent , StorageUrl }
	Data defined properties for different editor widgets. More...

Signals inherited from QgsEditorWidgetWrapper
void	constraintResultVisibleChanged (bool visible)
	Emit this signal when the constraint result visibility changed.

void	constraintStatusChanged (const QString &constraint, const QString &desc, const QString &err, QgsEditorWidgetWrapper::ConstraintResult status)
	Emit this signal when the constraint status changed.

Q_DECL_DEPRECATED void	valueChanged (const QVariant &value)
	Emit this signal, whenever the value changed.

void	valuesChanged (const QVariant &value, const QVariantList &additionalFieldValues=QVariantList())
	Emit this signal, whenever the value changed.

Signals inherited from QgsWidgetWrapper
void	contextChanged ()
	Signal when QgsAttributeEditorContext mContext changed.

Static Public Member Functions inherited from QgsEditorWidgetWrapper
static QgsEditorWidgetWrapper *	fromWidget (QWidget *widget)
	Will return a wrapper for a given widget.

static bool	isInTable (const QWidget *parent)
	Check if the given widget or one of its parent is a QTableView.

Static Public Member Functions inherited from QgsWidgetWrapper
static QgsWidgetWrapper *	fromWidget (QWidget *widget)
	Will return a wrapper for a given widget.

static const QgsPropertiesDefinition &	propertyDefinitions ()
	Returns the editor widget property definitions.

Protected Attributes inherited from QgsWidgetWrapper
QgsPropertyCollection	mPropertyCollection
	Data defined property collection.

Properties inherited from QgsEditorWidgetWrapper
ConstraintResult	constraintResult

bool	constraintResultVisible

Detailed Description

Wraps a value relation widget.

This widget will offer a combobox with values from another layer referenced by a foreign key (a constraint may be set but is not required on data level). This is useful for having value lists on a separate layer containing codes and their translation to human readable names.

Options:

Layer The id of the referenced layer.
Key The key field on the referenced layer (code).
Value The value field on the referenced layer (human readable name).
AllowMulti If set to true, will allow multiple selections. This requires the data type to be a string. This does NOT work with normalized database structures.
AllowNull Will offer NULL as a possible value.
FilterExpression If not empty, will be used as expression. Only if this evaluates to true, the value will be shown.
OrderByValue Will order by value instead of key.

Note: not available in Python bindings

Definition at line 136 of file qgsvaluerelationwidgetwrapper.h.

Constructor & Destructor Documentation

◆ QgsValueRelationWidgetWrapper()

QgsValueRelationWidgetWrapper::QgsValueRelationWidgetWrapper	(	QgsVectorLayer *	layer,
		int	fieldIdx,
		QWidget *	editor = `nullptr`,
		QWidget *	parent = `nullptr`
	)

explicit

Constructor for QgsValueRelationWidgetWrapper.

The layer and fieldIdx arguments specify the vector layer field associated with the wrapper.

The editor argument indicates the editor widget to use with the wrapper. This can be nullptr if a new widget should be autogenerated.

A parent widget for this widget wrapper and the created widget can also be specified.

Definition at line 240 of file qgsvaluerelationwidgetwrapper.cpp.

Member Function Documentation

◆ createWidget()

QWidget * QgsValueRelationWidgetWrapper::createWidget ( QWidget * parent )

overrideprotectedvirtual

This method should create a new widget with the provided parent.

This will only be called if the form did not already provide a widget, so it is not guaranteed to be called! You should not do initialization stuff, which also has to be done for custom editor widgets inside this method. Things like filling comboboxes and assigning other data which will also be used to make widgets on forms created in the QtDesigner usable should be assigned in initWidget().

Parameters

parent You should set this parent on the created widget.

Returns: A new widget

Implements QgsWidgetWrapper.

Definition at line 315 of file qgsvaluerelationwidgetwrapper.cpp.

◆ initWidget()

void QgsValueRelationWidgetWrapper::initWidget ( QWidget * editor )

overrideprotectedvirtual

This method should initialize the editor widget with runtime data.

Fill your comboboxes here.

Parameters

editor The widget which will represent this attribute editor in a form.

Reimplemented from QgsWidgetWrapper.

Definition at line 343 of file qgsvaluerelationwidgetwrapper.cpp.

◆ parentFormValueChanged

void QgsValueRelationWidgetWrapper::parentFormValueChanged	(	const QString &	attribute,
		const QVariant &	value
	)

overrideslot

Definition at line 672 of file qgsvaluerelationwidgetwrapper.cpp.

◆ setEnabled()

void QgsValueRelationWidgetWrapper::setEnabled ( bool enabled )

overridevirtual

Is used to enable or disable the edit functionality of the managed widget.

By default this will enable or disable the whole widget

Parameters

enabled Enable or Disable?

Reimplemented from QgsEditorWidgetWrapper.

Definition at line 657 of file qgsvaluerelationwidgetwrapper.cpp.

◆ setFeature()

void QgsValueRelationWidgetWrapper::setFeature ( const QgsFeature & feature )

overrideprotectedvirtual

Will be called when the feature changes.

Is forwarded to the slot setValue() and updates the widget cache if the filter expression context contains values from the current feature

Parameters

feature The new feature

Implements QgsWidgetWrapper.

Definition at line 497 of file qgsvaluerelationwidgetwrapper.cpp.

◆ showIndeterminateState()

void QgsValueRelationWidgetWrapper::showIndeterminateState ( )

overridevirtual

Sets the widget to display in an indeterminate "mixed value" state.

Reimplemented from QgsEditorWidgetWrapper.

Definition at line 641 of file qgsvaluerelationwidgetwrapper.cpp.

◆ valid()

bool QgsValueRelationWidgetWrapper::valid ( ) const

overrideprotectedvirtual

Returns true if the widget has been properly initialized.

This acts as hint for the calling party if this wrapper can be used after initializing it. If it cannot be used this is a hint to the caller that he may try to find another suitable widget type instead.

Returns: Validity status of this widget.

Implements QgsWidgetWrapper.

Definition at line 379 of file qgsvaluerelationwidgetwrapper.cpp.

◆ value()

QVariant QgsValueRelationWidgetWrapper::value ( ) const

overridevirtual

Will be used to access the widget's value.

Read the value from the widget and return it properly formatted to be saved in the attribute.

If an invalid variant is returned this will be interpreted as no change. Be sure to return a NULL QVariant if it should be set to NULL.

Returns: The current value the widget represents

Implements QgsEditorWidgetWrapper.

Definition at line 245 of file qgsvaluerelationwidgetwrapper.cpp.

◆ widgetValueChanged()

void QgsValueRelationWidgetWrapper::widgetValueChanged	(	const QString &	attribute,
		const QVariant &	newValue,
		bool	attributeChanged
	)

protected

Will be called when a value in the current edited form or table row changes.

Update widget cache if the value is used in the filter expression and stores current field values to be used in expression form scope context

Parameters

attribute	The name of the attribute that changed.
newValue	The new value of the attribute.
attributeChanged	If `true`, it corresponds to an actual change of the feature attribute

Since: QGIS 3.2.0

Definition at line 458 of file qgsvaluerelationwidgetwrapper.cpp.

Friends And Related Symbol Documentation

◆ QgsValueRelationWidgetFactory

friend class QgsValueRelationWidgetFactory

friend

Definition at line 223 of file qgsvaluerelationwidgetwrapper.h.

◆ TestQgsValueRelationWidgetWrapper

friend class TestQgsValueRelationWidgetWrapper

friend

Definition at line 224 of file qgsvaluerelationwidgetwrapper.h.

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

/build/qgis-3.41.0+git20241116+25ec5511245+99sid/src/gui/editorwidgets/qgsvaluerelationwidgetwrapper.h
/build/qgis-3.41.0+git20241116+25ec5511245+99sid/src/gui/editorwidgets/qgsvaluerelationwidgetwrapper.cpp

Public Slots

Public Member Functions

Protected Member Functions

Friends

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ QgsValueRelationWidgetWrapper()

Member Function Documentation

◆ createWidget()

◆ initWidget()

◆ parentFormValueChanged

◆ setEnabled()

◆ setFeature()

◆ showIndeterminateState()

◆ valid()

◆ value()

◆ widgetValueChanged()

Friends And Related Symbol Documentation

◆ QgsValueRelationWidgetFactory

◆ TestQgsValueRelationWidgetWrapper