Class: QgsFieldModel¶

class qgis.core.QgsFieldModel¶

Bases: PyQt5.QtCore.QAbstractItemModel

The QgsFieldModel class is a model to display the list of fields in widgets (optionally associated with a vector layer). If allowed, expressions might be added to the end of the model. It can be associated with a QgsMapLayerModel to dynamically display a layer and its fields.

QgsFieldModel(parent: QObject = None) Constructor for QgsFieldModel - creates a model to display the fields of a given layer.

Enums

CustomRole

Bases: enum.IntEnum

FieldRoles

alias of CustomRole

Methods

allowEmptyFieldName

Returns True if the model allows the empty field ("not set") choice.

allowExpression

Returns True if the model allows custom expressions to be created and displayed.

beginInsertColumns

beginInsertRows

beginMoveColumns

beginMoveRows

beginRemoveColumns

beginRemoveRows

beginResetModel

changePersistentIndex

changePersistentIndexList

childEvent

columnCount

param parent:

connectNotify

createIndex

customEvent

data

param index:

decodeData

disconnectNotify

encodeData

endInsertColumns

endInsertRows

endMoveColumns

endMoveRows

endRemoveColumns

endRemoveRows

endResetModel

fieldToolTip

Returns a HTML formatted tooltip string for a field, containing details like the field name, alias and type.

fieldToolTipExtended

Returns a HTML formatted tooltip string for a field, containing details like the field name, alias, type and expression.

fields

Returns the fields currently shown in the model.

index

param row:

indexFromName

Returns the index corresponding to a given fieldName.

isField

Returns True if a string represents a field reference, or False if it is an expression consisting of more than direct field reference.

isSignalConnected

layer

Returns the layer associated with the model.

parent

param child:

persistentIndexList

receivers

removeExpression

Removes any custom expression from the model.

resetInternalData

rowCount

param parent:

sender

senderSignalIndex

setAllowEmptyFieldName

Sets whether an optional empty field ("not set") option is present in the model.

setAllowExpression

Sets whether custom expressions are accepted and displayed in the model.

setExpression

Sets a single expression to be added after the fields at the end of the model.

setFields

Manually sets the fields to use for the model.

setLayer

Set the layer from which fields are displayed.

timerEvent

updateModel

Called when the model must be updated.

class CustomRole(value)¶

Bases: enum.IntEnum

Custom model roles.

Note

Prior to QGIS 3.36 this was available as QgsFieldModel.FieldRoles

Added in version 3.36.

FieldNameRole: Return field name if index corresponds to a field
FieldIndexRole: Return field index if index corresponds to a field
ExpressionRole: Return field name or expression
IsExpressionRole: Return if index corresponds to an expression
ExpressionValidityRole: Return if expression is valid or not
FieldTypeRole: Return the field type (if a field, return QVariant if expression)
FieldOriginRole: Return the field origin (if a field, returns QVariant if expression)
IsEmptyRole: Return if the index corresponds to the empty value
EditorWidgetType: Editor widget type
JoinedFieldIsEditable: True if a joined field is editable (returns QVariant if not a joined field)
FieldIsWidgetEditable: True if a is editable from the widget

baseClass¶: alias of QgsFieldModel

FieldRoles¶: alias of CustomRole

allowEmptyFieldName(self) → bool¶

Returns True if the model allows the empty field (“not set”) choice.

See also

setAllowEmptyFieldName()

Return type:: bool

allowExpression(self) → bool¶

Returns True if the model allows custom expressions to be created and displayed.

See also

setAllowExpression()

Return type:: bool

beginInsertColumns(self, QModelIndex, int, int)¶

beginInsertRows(self, QModelIndex, int, int)¶

beginMoveColumns(self, QModelIndex, int, int, QModelIndex, int) → bool¶

beginMoveRows(self, QModelIndex, int, int, QModelIndex, int) → bool¶

beginRemoveColumns(self, QModelIndex, int, int)¶

beginRemoveRows(self, QModelIndex, int, int)¶

beginResetModel(self)¶

changePersistentIndex(self, QModelIndex, QModelIndex)¶

changePersistentIndexList(self, Iterable[QModelIndex], Iterable[QModelIndex])¶

childEvent(self, QChildEvent)¶

columnCount(self, parent: QModelIndex) → int¶

Parameters:: parent (QModelIndex)
Return type:: int

connectNotify(self, QMetaMethod)¶

createIndex(self, int, int, object: object = 0) → QModelIndex¶

customEvent(self, QEvent)¶

data(self, index: QModelIndex, role: int) → Any¶

Parameters:

index (QModelIndex)
role (int)

Return type:

Any

decodeData(self, int, int, QModelIndex, QDataStream) → bool¶

disconnectNotify(self, QMetaMethod)¶

encodeData(self, Iterable[QModelIndex], QDataStream)¶

endInsertColumns(self)¶

endInsertRows(self)¶

endMoveColumns(self)¶

endMoveRows(self)¶

endRemoveColumns(self)¶

endRemoveRows(self)¶

endResetModel(self)¶

fieldToolTip(field: QgsField) → str¶

Returns a HTML formatted tooltip string for a field, containing details like the field name, alias and type.

Parameters:: field (QgsField)
Return type:: str

fieldToolTipExtended(field: QgsField, layer: QgsVectorLayer) → str¶

Returns a HTML formatted tooltip string for a field, containing details like the field name, alias, type and expression.

Added in version 3.14.

Parameters:

field (QgsField)
layer (QgsVectorLayer)

Return type:

str

fields(self) → QgsFields¶

Returns the fields currently shown in the model.

This will either be fields from the associated layer() or the fields manually set by a call to setFields().

Added in version 3.14.

Return type:: QgsFields

index(self, row: int, column: int, parent: QModelIndex = QModelIndex()) → QModelIndex¶

Parameters:

row (int)
column (int)
parent (QModelIndex = QModelIndex())

Return type:

QModelIndex

indexFromName(self, fieldName: str) → QModelIndex¶

Returns the index corresponding to a given fieldName.

Parameters:: fieldName (str)
Return type:: QModelIndex

isField(self, expression: str) → bool¶

Returns True if a string represents a field reference, or False if it is an expression consisting of more than direct field reference.

Parameters:: expression (str)
Return type:: bool

isSignalConnected(self, QMetaMethod) → bool¶

layer(self) → QgsVectorLayer¶

Returns the layer associated with the model.

See also

setLayer()

Return type:: QgsVectorLayer

parent(self, child: QModelIndex) → QModelIndex¶

Parameters:: child (QModelIndex)
Return type:: QModelIndex

persistentIndexList(self) → List[QModelIndex]¶

receivers(self, PYQT_SIGNAL) → int¶

removeExpression(self)¶: Removes any custom expression from the model.

See also

setExpression()

See also

allowExpression()

resetInternalData(self)¶

rowCount(self, parent: QModelIndex = QModelIndex()) → int¶

Parameters:: parent (QModelIndex = QModelIndex())
Return type:: int

sender(self) → QObject¶

senderSignalIndex(self) → int¶

setAllowEmptyFieldName(self, allowEmpty: bool)¶

Sets whether an optional empty field (“not set”) option is present in the model.

See also

allowEmptyFieldName()

Parameters:: allowEmpty (bool)

setAllowExpression(self, allowExpression: bool)¶

Sets whether custom expressions are accepted and displayed in the model.

See also

allowExpression()

See also

setExpression()

Parameters:: allowExpression (bool)

setExpression(self, expression: str)¶

Sets a single expression to be added after the fields at the end of the model.

See also

setAllowExpression()

See also

allowExpression()

See also

removeExpression()

Parameters:: expression (str)

setFields(self, fields: QgsFields)¶

Manually sets the fields to use for the model.

This method should only be used when the model ISN’T associated with a layer() and needs to show the fields from an arbitrary field collection instead. Calling setFields() will automatically clear any existing layer().

See also

fields()

Added in version 3.14.

Parameters:: fields (QgsFields)

setLayer(self, layer: QgsVectorLayer)¶

Set the layer from which fields are displayed.

See also

layer()

Parameters:: layer (QgsVectorLayer)

timerEvent(self, QTimerEvent)¶

updateModel(self)¶: Called when the model must be updated.