Class: QgsAbstractProcessingParameterWidgetWrapper

class qgis.gui.QgsAbstractProcessingParameterWidgetWrapper(parameter: QgsProcessingParameterDefinition = None, type: QgsProcessingGui.WidgetType = QgsProcessingGui.Standard, parent: QObject = None)

Bases: PyQt5.QtCore.QObject, qgis._core.QgsExpressionContextGenerator

Constructor for QgsAbstractProcessingParameterWidgetWrapper, for the specified parameter definition and dialog type.

A widget wrapper for Processing parameter value widgets.

Widget wrappers are used to create widgets for individual Processing parameters, and handle retrieving and setting the current value for those parameters.

Widget wrappers can be created for different dialog types, allowing different appearance and behavior of widgets depending on whether they are being created for use in a standard algorithm dialog, a batch processing dialog, or a modeler dialog.

Individual widget wrappers are not usually created directly, instead they are constructed through the central registry, via calls to QgsGui.processingGuiRegistry()->createParameterWidgetWrapper().

New in version 3.4: Enums

Methods

childEvent

connectNotify

createExpressionContext

createLabel

Creates a new label to accompany widgets created by the wrapper.

createWidget

Creates a new widget which allows customization of the parameter’s value.

createWrappedLabel

Creates and returns a new label to accompany widgets created by the wrapper.

createWrappedWidget

Creates and return a new wrapped widget which allows customization of the parameter’s value.

customEvent

disconnectNotify

isSignalConnected

linkedVectorLayer

Returns the optional vector layer associated with this widget wrapper, or None if no vector layer is applicable.

parameterDefinition

Returns the parameter definition associated with this wrapper.

parameterValue

Returns the current value of the parameter.

postInitialize

Called after all wrappers have been created within a particular dialog or context, allowing the wrapper to connect to the wrappers of other, related parameters.

receivers

registerProcessingContextGenerator

Registers a Processing context generator class that will be used to retrieve a Processing context for the wrapper when required.

sender

senderSignalIndex

setDialog

Sets the parent dialog in which the wrapper is shown.

setParameterValue

Sets the current value for the parameter.

setWidgetContext

Sets the context in which the Processing parameter widget is shown, e.g., the parent model algorithm, a linked map canvas, and other relevant information which allows the widget to fine-tune its behavior.

setWidgetValue

Sets the current value for the parameter to show in the widget.

timerEvent

type

Returns the dialog type for which widgets and labels will be created by this wrapper.

widgetContext

Returns the context in which the Processing parameter widget is shown, e.g., the parent model algorithm, a linked map canvas, and other relevant information which allows the widget to fine-tune its behavior.

widgetValue

Returns the current value of the parameter.

wrappedLabel

Returns the current wrapped label, if any.

wrappedWidget

Returns the current wrapped widget, if any.

Signals

widgetValueHasChanged

Emitted whenever the parameter value (as defined by the wrapped widget) is changed.

Attributes

param

parameterDefinition(self) -> QgsProcessingParameterDefinition Returns the parameter definition associated with this wrapper.

childEvent()
connectNotify()
createExpressionContext(self) → QgsExpressionContext
createLabel(self) → QLabel

Creates a new label to accompany widgets created by the wrapper.

The caller takes ownership of the returned label. Some parameter type and dialog type combinations will return None for this method. If None is returned, then no label should be shown for the parameter’s widget (i.e. the label is embedded inside the widget itself).

See also

createWidget()

createWidget(self) → QWidget

Creates a new widget which allows customization of the parameter’s value.

The caller takes ownership of the returned widget.

See also

createLabel()

createWrappedLabel(self) → QLabel

Creates and returns a new label to accompany widgets created by the wrapper.

The caller takes ownership of the returned label. Some parameter type and dialog type combinations will return None for this method. If None is returned, then no label should be shown for the parameter’s widget (i.e. the label is embedded inside the widget itself).

The wrapped label can be retrieved at a later stage by calling wrappedLabel().

createWrappedWidget(self, context: QgsProcessingContext) → QWidget

Creates and return a new wrapped widget which allows customization of the parameter’s value.

The caller takes ownership of the returned widget. The wrapped widget can be retrieved at a later stage by calling wrappedWidget().

The supplied context is used while initializing the widget to the parameter’s default value.

customEvent()
disconnectNotify()
isSignalConnected()
linkedVectorLayer(self) → QgsVectorLayer

Returns the optional vector layer associated with this widget wrapper, or None if no vector layer is applicable.

This is used to correctly generate expression contexts within the GUI, e.g. to allow expression buttons and property override buttons to correctly show the appropriate vector layer fields.

New in version 3.6.

param

parameterDefinition(self) -> QgsProcessingParameterDefinition Returns the parameter definition associated with this wrapper.

parameterDefinition(self) → QgsProcessingParameterDefinition

Returns the parameter definition associated with this wrapper.

parameterValue(self) → Any

Returns the current value of the parameter.

postInitialize(self, wrappers: object)

Called after all wrappers have been created within a particular dialog or context, allowing the wrapper to connect to the wrappers of other, related parameters.

receivers()
registerProcessingContextGenerator(self, generator: QgsProcessingContextGenerator)

Registers a Processing context generator class that will be used to retrieve a Processing context for the wrapper when required.

sender()
senderSignalIndex()
setDialog(self, dialog: QDialog)

Sets the parent dialog in which the wrapper is shown.

New in version 3.8.

setParameterValue(self, value: Any, context: QgsProcessingContext)

Sets the current value for the parameter.

The context argument is used to specify the wider Processing context which the current value is associated with.

See also

parameterValue()

setWidgetContext(self, context: QgsProcessingParameterWidgetContext)

Sets the context in which the Processing parameter widget is shown, e.g., the parent model algorithm, a linked map canvas, and other relevant information which allows the widget to fine-tune its behavior.

Subclasses should take care to call the base class method when reimplementing this method.

See also

widgetContext()

setWidgetValue(self, value: Any, context: QgsProcessingContext)

Sets the current value for the parameter to show in the widget.

The context argument is used to specify the wider Processing context which the current value is associated with.

See also

widgetValue()

timerEvent()
type(self) → QgsProcessingGui.WidgetType

Returns the dialog type for which widgets and labels will be created by this wrapper.

widgetContext(self) → QgsProcessingParameterWidgetContext

Returns the context in which the Processing parameter widget is shown, e.g., the parent model algorithm, a linked map canvas, and other relevant information which allows the widget to fine-tune its behavior.

widgetValue(self) → Any

Returns the current value of the parameter.

See also

setWidgetValue()

widgetValueHasChanged

Emitted whenever the parameter value (as defined by the wrapped widget) is changed. [signal]

wrappedLabel(self) → QLabel

Returns the current wrapped label, if any.

wrappedWidget(self) → QWidget

Returns the current wrapped widget, if any.