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magicgui.widgets.bases#

The magicgui.widgets.bases module contains the base classes for all widgets.

While most users will never instantiate these classes directly, the methods and properties of these classes are inherited by all widgets, and define the common API for all widgets. Therefore, it is worth being aware of the type of widget you are working with.

Summary#

Widget Description
Widget Basic Widget, wrapping a class that implements WidgetProtocol.
ButtonWidget Widget with a value, Wraps a widget implementing the ButtonWidgetProtocol.
CategoricalWidget Widget with a value and choices. Wraps CategoricalWidgetProtocol.
BaseContainerWidget Widget that can contain other widgets.
ContainerWidget Container widget that can insert/remove child widgets.
ValuedContainerWidget Container-type ValueWidget.
DialogWidget Modal Container.
MainWindowWidget Top level Application widget that can contain other widgets.
RangedWidget Widget with a constrained value. Wraps RangedWidgetProtocol.
SliderWidget Widget with a constrained value and orientation. Wraps SliderWidgetProtocol.
ValueWidget Widget with a value, Wraps ValueWidgetProtocol.
BaseValueWidget An abstract base class for widgets that have a value.

Class Hierarchy#

In visual form, the widget class hierarchy looks like this:

classDiagram
    Widget <|-- BaseValueWidget
    BaseValueWidget <|-- ValueWidget
    Widget <|-- BaseContainerWidget
    BackendWidget ..|> WidgetProtocol : implements a
    ValueWidget <|-- RangedWidget
    ValueWidget <|-- ButtonWidget
    ValueWidget <|-- CategoricalWidget
    RangedWidget <|-- SliderWidget
    BaseContainerWidget <|-- ContainerWidget
    BaseContainerWidget <|-- ValuedContainerWidget
    BaseValueWidget <|-- ValuedContainerWidget
    Widget --* WidgetProtocol : controls a
    <<Interface>> WidgetProtocol
    class WidgetProtocol {
        _mgui_get_X()
        _mgui_set_X()
    }
    class Widget{
        name: str
        annotation: Any
        label: str
        tooltip: str
        visible: bool
        enabled: bool
        native: Any
        height: int
        width: int
        hide()
        show()
        close()
        render()
    }
    class BaseValueWidget{
        value: Any
        changed: SignalInstance
        bind(value, call) Any
        unbind()
    }
    class ValueWidget{
    }
    class RangedWidget{
        value: float | tuple
        min: float
        max: float
        step: float
        adaptive_step: bool
        range: tuple[float, float]
    }
    class SliderWidget{
        orientation: str
    }
    class ButtonWidget{
        value: bool
        clicked: SignalInstance
        text: str
    }
    class CategoricalWidget{
        choices: List[Any]
    }
    class BaseContainerWidget{
        widgets: List[Widget]
        labels: bool
        layout: str
        margins: tuple[int, int, int, int]
        reset_choices()
        asdict() Dict[str, Any]
        update(mapping)
    }

    click Widget href "#magicgui.widgets.bases.Widget"
    click BaseValueWidget href "#magicgui.widgets.bases.BaseValueWidget"
    click ValueWidget href "#magicgui.widgets.bases.ValueWidget"
    click RangedWidget href "#magicgui.widgets.bases.RangedWidget"
    click SliderWidget href "#magicgui.widgets.bases.SliderWidget"
    click ButtonWidget href "#magicgui.widgets.bases.ButtonWidget"
    click CategoricalWidget href "#magicgui.widgets.bases.CategoricalWidget"
    click BaseContainerWidget href "#magicgui.widgets.bases.BaseContainerWidget"

Base Widget Classes#

magicgui.widgets.bases.Widget #

Basic Widget, wrapping a class that implements WidgetProtocol.

Parameters:

  • widget_type (type[WidgetProtocol]) –

    A class implementing a widget protocol. Will be instantiated during init.

  • name (str, default: '' ) –

    The name of the parameter represented by this widget. by default ""

  • annotation (Any, default: None ) –

    The type annotation for the parameter represented by the widget, by default None

  • label (str, default: None ) –

    A string to use for an associated Label widget (if this widget is being shown in a Container widget, and labels are on). By default, name will be used. Note: name refers the name of the parameter, as might be used in a signature, whereas label is just the label for that widget in the GUI.

  • tooltip (str, default: None ) –

    A tooltip to display when hovering over the widget.

  • visible (bool, default: None ) –

    Whether the widget is visible, by default True.

  • enabled (bool, default: True ) –

    Whether the widget is enabled, by default True.

  • gui_only (bool, default: False ) –

    If True, widget is excluded from any function signature representation. by default False. (This will likely be deprecated.)

  • parent (Any, default: None ) –

    Optional parent widget of this widget. CAREFUL: if a parent is set, and subsequently deleted, this widget will likely be deleted as well (depending on the backend), and will no longer be usable.

  • backend_kwargs (dict, default: None ) –

    keyword argument to pass to the backend widget constructor.

annotation: Any property writable #

Return type annotation for the parameter represented by the widget.

ForwardRefs will be resolve when setting the annotation.

enabled: bool property writable #

Whether widget is enabled (editable).

height: int property writable #

Return the current height of the widget.

label: str property writable #

Return a label to use for this widget when present in Containers.

max_height: int property writable #

Get the maximum height of the widget.

max_width: int property writable #

Get the maximum width of the widget.

min_height: int property writable #

Get the minimum height of the widget.

min_width: int property writable #

Get the minimum width of the widget.

native: Any property #

Return native backend widget.

Note this is the widget that contains the layout, and not any parent widgets of this (e.g. a parent widget that is used to enable scroll bars)

options: dict property #

Return options currently being used in this widget.

param_kind: inspect._ParameterKind property writable #

Return :attr:inspect.Parameter.kind represented by this widget.

Used in building signatures from multiple widgets, by default :attr:~inspect.Parameter.POSITIONAL_OR_KEYWORD

parent: Widget property writable #

Return the parent widget.

parent_changed: SignalInstance property #

Signal emitted when the parent of the widget changes.

root_native_widget: Any property #

Return the root native backend widget.

This can be different from the .native widget if the layout is a child of some other widget, e.g. a widget used to enable scroll bars.

tooltip: str | None property writable #

Get the tooltip for this widget.

visible: bool property writable #

Return whether widget is visible.

widget_type: str property #

Return type of widget.

width: int property writable #

Return the current width of the widget.

__repr__() -> str #

Return representation of widget of instance.

close() -> None #

Close widget.

hide() -> None #

Hide widget.

alias for widget.visible = False

render() -> np.ndarray #

Return an RGBA (MxNx4) numpy array bitmap of the rendered widget.

show(run: bool = False) -> Widget #

Show widget.

alias for widget.visible = True

Parameters:

  • run (bool, default: False ) –

    Whether to start the application event loop, by default False

shown() -> Iterator[Application] #

Context manager to show the widget.

magicgui.widgets.bases.ButtonWidget #

Bases: ValueWidget[bool]

Widget with a value, Wraps a widget implementing the ButtonWidgetProtocol.

see ButtonWidgetProtocol.

Parameters:

  • value (bool, default: Undefined ) –

    The starting state of the widget.

  • text (str, default: None ) –

    The text to display on the button. If not provided, will use name.

  • bind (Callable[[ValueWidget], Any] | Any, default: Undefined ) –

    A value or callback to bind this widget. If provided, whenever widget.value is accessed, the value provided here will be returned instead. bind may be a callable, in which case bind(self) will be returned (i.e. your bound callback must accept a single parameter, which is this widget instance).

  • nullable (bool, default: False ) –

    If True, the widget will accepts None as a valid value, by default False.

  • **base_widget_kwargs (Any, default: {} ) –

    All additional keyword arguments are passed to the base magicgui.widgets.Widget constructor.

clicked: SignalInstance property #

Alias for changed event.

options: dict property #

Return options currently being used in this widget.

text: str property writable #

Text of the widget.

magicgui.widgets.bases.CategoricalWidget #

Bases: ValueWidget[T]

Widget with a value and choices. Wraps CategoricalWidgetProtocol.

Parameters:

  • value (Any, default: Undefined ) –

    The initially selected choice.

  • choices (Enum, Iterable, or Callable, default: () ) –

    Available choices displayed in the combo box.

  • bind (Callable[[ValueWidget], Any] | Any, default: Undefined ) –

    A value or callback to bind this widget. If provided, whenever widget.value is accessed, the value provided here will be returned instead. bind may be a callable, in which case bind(self) will be returned (i.e. your bound callback must accept a single parameter, which is this widget instance).

  • nullable (bool, default: False ) –

    If True, the widget will accepts None as a valid value, by default False.

  • **base_widget_kwargs (Any, default: {} ) –

    All additional keyword arguments are passed to the base magicgui.widgets.Widget constructor.

choices: tuple[T | None, ...] property writable #

Available value choices for this widget.

current_choice: str property #

Return the text of the currently selected choice.

options: dict property #

Return options currently being used in this widget.

value: T property writable #

Return current value of the widget.

__len__() -> int #

Return the number of choices.

del_choice(choice_name: str) -> None #

Delete the provided choice_name and associated data.

get_choice(choice_name: str) -> T #

Get data for the provided choice_name.

reset_choices(*_: Any) -> None #

Reset choices to the default state.

If self._default_choices is a callable, this may NOT be the exact same set of choices as when the widget was instantiated, if the callable relies on external state.

set_choice(choice_name: str, data: Any | None = None) -> None #

Set data for the provided choice_name.

magicgui.widgets.bases.BaseContainerWidget #

Bases: Widget, _OrientationMixin, Sequence[WidgetVar]

Widget that can contain other widgets.

Wraps a widget that implements ContainerProtocol.

Parameters:

  • widgets (Sequence[Widget], default: () ) –

    A sequence of widgets with which to initialize the container, by default None.

  • layout (str, default: 'vertical' ) –

    The layout for the container. must be one of {'horizontal', 'vertical'}. by default "vertical"

  • scrollable (bool, default: False ) –

    Whether to enable scroll bars or not. If enabled, scroll bars will only appear along the layout direction, not in both directions.

  • labels (bool, default: True ) –

    Whether each widget should be shown with a corresponding Label widget to the left, by default True. Note: the text for each widget defaults to widget.name, but can be overridden by setting widget.label.

  • **base_widget_kwargs (Any, default: {} ) –

    All additional keyword arguments are passed to the base magicgui.widgets.Widget constructor.

labels: bool property writable #

Whether widgets are presented with labels.

layout: str property writable #

Return the layout of the widget.

margins: tuple[int, int, int, int] property writable #

Return margin between the content and edges of the container.

__getattr__(name: str) -> WidgetVar #

Return attribute name. Will return a widget if present.

__getitem__(key: int | str | slice) -> WidgetVar | MutableSequence[WidgetVar] #

Get item by integer, str, or slice.

__len__() -> int #

Return the count of widgets.

reset_choices(*_: Any) -> None #

Reset choices for all Categorical subWidgets to the default state.

If widget._default_choices is a callable, this may NOT be the exact same set of choices as when the widget was instantiated, if the callable relies on external state.

magicgui.widgets.bases.ContainerWidget #

Bases: BaseContainerWidget[WidgetVar], MutableSequence[WidgetVar]

Container widget that can insert/remove child widgets.

A ContainerWidget behaves like a python list of Widget objects. Subwidgets can be accessed using integer or slice-based indexing (container[0]), as well as by widget name (container.<widget_name>). Widgets can be added with append or insert, and removed with del or pop, etc...

There is a tight connection between a ContainerWidget and an inspect.Signature object, just as there is a tight connection between individual Widgetobjects an an :class:inspect.Parameter object. The signature representation of a ContainerWidget (with the current settings as default values) is accessible with the :meth:~ContainerWidget.__signature__ method (or by using :func:inspect.signature from the standard library)

For a ContainerWidget subclass that is tightly coupled to a specific function signature (as in the "classic" magicgui decorator), see magicgui.widgets.FunctionGui.

__signature__: MagicSignature property #

Return a MagicSignature object representing the current state of the gui.

__delattr__(name: str) -> None #

Delete a widget by name.

__delitem__(key: int | slice) -> None #

Delete a widget by integer or slice index.

__dir__() -> list[str] #

Add subwidget names to the dir() call for this widget.

__repr__() -> str #

Return a repr.

__setattr__(name: str, value: Any) -> None #

Set attribute name. Prevents changing widget if present, (use del).

__setitem__(key: Any, value: Any) -> NoReturn #

Prevent assignment by index.

asdict() -> dict[str, Any] #

Return state of widget as dict.

from_callable(obj: Callable, gui_options: dict | None = None, **kwargs: Unpack[ContainerKwargs]) -> Container classmethod #

Create a Container widget from a callable object.

In most cases, it will be preferable to create a FunctionGui instead.

from_signature(sig: inspect.Signature, **kwargs: Unpack[ContainerKwargs]) -> Container classmethod #

Create a Container widget from an inspect.Signature object.

index(value: Any, start: int = 0, stop: int = 9223372036854775807) -> int #

Return index of a specific widget instance (or widget name).

insert(key: int, widget: WidgetVar) -> None #

Insert widget at key.

remove(value: Widget | str) -> None #

Remove a widget instance (may also be string name of widget).

update(mapping: Mapping | Iterable[tuple[str, Any]] | None = None, **kwargs: Any) -> None #

Update the parameters in the widget from a mapping, iterable, or kwargs.

magicgui.widgets.bases.ValuedContainerWidget #

Bases: BaseContainerWidget[Widget], BaseValueWidget[T], Generic[T]

Container-type ValueWidget.

magicgui.widgets.bases.DialogWidget #

Bases: ContainerWidget

Modal Container.

exec() -> bool #

Show the dialog, and block.

Return True if the dialog was accepted, False if rejected.

magicgui.widgets.bases.MainWindowWidget #

Bases: ContainerWidget

Top level Application widget that can contain other widgets.

create_menu_item(menu_name: str, item_name: str, callback: Callable | None = None, shortcut: str | None = None) -> None #

Create a menu item item_name under menu menu_name.

menu_name will be created if it does not already exist.

magicgui.widgets.bases.RangedWidget #

Bases: ValueWidget[T]

Widget with a constrained value. Wraps RangedWidgetProtocol.

Parameters:

  • value (Any, default: Undefined ) –

    The starting value for the widget.

  • min (float, default: Undefined ) –

    The minimum allowable value, by default 0 (or value if value is less than 0)

  • max (float, default: Undefined ) –

    The maximum allowable value, by default 999 (or value if value is greater than 999)

  • step (float, default: Undefined ) –

    The step size for incrementing the value, by default adaptive step is used

  • bind (Callable[[ValueWidget], Any] | Any, default: Undefined ) –

    A value or callback to bind this widget. If provided, whenever widget.value is accessed, the value provided here will be returned instead. bind may be a callable, in which case bind(self) will be returned (i.e. your bound callback must accept a single parameter, which is this widget instance).

  • nullable (bool, default: False ) –

    If True, the widget will accepts None as a valid value, by default False.

  • **base_widget_kwargs (Any, default: {} ) –

    All additional keyword arguments are passed to the base magicgui.widgets.Widget constructor.

adaptive_step: bool property writable #

Whether the step size is adaptive.

Adaptive decimal step means that the step size will continuously be adjusted to one power of ten below the current value. So when the value is 1100, the step is set to 100, so stepping up once increases it to 1200. For 1200 stepping up takes it to 1300. For negative values, stepping down from -1100 goes to -1200.

max: float property writable #

Maximum allowable value for the widget.

min: float property writable #

Minimum allowable value for the widget.

options: dict property #

Return options currently being used in this widget.

range: tuple[float, float] property writable #

Range of allowable values for the widget.

step: float | None property writable #

Step size for widget values (None if adaptive step is turned on).

set_value(value: T) -> None #

Set widget value, will raise Value error if not within min/max.

magicgui.widgets.bases.SliderWidget #

Bases: RangedWidget[T], _OrientationMixin

Widget with a constrained value and orientation. Wraps SliderWidgetProtocol.

Parameters:

  • value (Any, default: Undefined ) –

    The starting value for the widget.

  • min (float, default: Undefined ) –

    The minimum allowable value, by default 0 (or value if value is less than 0)

  • max (float, default: Undefined ) –

    The maximum allowable value, by default 999 (or value if value is greater than 999)

  • step (float, default: Undefined ) –

    The step size for incrementing the value, by default adaptive step is used

  • orientation ((str, {'horizontal', 'vertical'}), default: 'horizontal' ) –

    The orientation for the slider, by default "horizontal"

  • readout (bool, default: True ) –

    Whether to show the editable spinbox next to the slider

  • tracking (bool, default: True ) –

    If tracking is enabled (the default), the slider emits the changed signal while the slider is being dragged. If tracking is disabled, the slider emits the changed signal only after the user releases the slider.

  • bind (Callable[[ValueWidget], Any] | Any, default: Undefined ) –

    A value or callback to bind this widget. If provided, whenever widget.value is accessed, the value provided here will be returned instead. bind may be a callable, in which case bind(self) will be returned (i.e. your bound callback must accept a single parameter, which is this widget instance).

  • nullable (bool, default: False ) –

    If True, the widget will accepts None as a valid value, by default False.

  • **base_widget_kwargs (Any, default: {} ) –

    All additional keyword arguments are passed to the base magicgui.widgets.Widget constructor.

options: dict property #

Return options currently being used in this widget.

readout: bool property writable #

Get visibility state of readout widget.

tracking: bool property writable #

Return whether slider tracking is enabled.

If tracking is enabled (the default), the slider emits the changed() signal while the slider is being dragged. If tracking is disabled, the slider emits the changed() signal only when the user releases the slider.

magicgui.widgets.bases.ValueWidget #

Bases: BaseValueWidget[T]

Widget with a value, Wraps ValueWidgetProtocol.

Parameters:

  • value (Any, default: Undefined ) –

    The starting value for the widget.

  • bind (Callable[[ValueWidget], Any] | Any, default: Undefined ) –

    A value or callback to bind this widget. If provided, whenever widget.value is accessed, the value provided here will be returned instead. bind may be a callable, in which case bind(self) will be returned (i.e. your bound callback must accept a single parameter, which is this widget instance).

  • nullable (bool, default: False ) –

    If True, the widget will accepts None as a valid value, by default False.

  • **base_widget_kwargs (Any, default: {} ) –

    All additional keyword arguments are passed to the base magicgui.widgets.Widget constructor.

get_value() -> T #

Callable version of self.value.

The main API is to use self.value, however, this is here in order to provide an escape hatch if trying to access the widget's value inside of a callback bound to self._bound_value.

magicgui.widgets.bases.BaseValueWidget #

Bases: Widget, ABC, Generic[T]

An abstract base class for widgets that have a value.

Subclasses must implement the get_value and set_value methods.

Parameters:

  • value (Any, default: Undefined ) –

    The starting value for the widget.

  • bind (Callable[[ValueWidget], Any] | Any, default: Undefined ) –

    A value or callback to bind this widget. If provided, whenever widget.value is accessed, the value provided here will be returned instead. bind may be a callable, in which case bind(self) will be returned (i.e. your bound callback must accept a single parameter, which is this widget instance).

  • nullable (bool, default: False ) –

    If True, the widget will accepts None as a valid value, by default False.

  • **base_widget_kwargs (Any, default: {} ) –

    All additional keyword arguments are passed to the base magicgui.widgets.Widget constructor.

annotation: Any property writable #

Return type annotation for the parameter represented by the widget.

ForwardRefs will be resolve when setting the annotation. If the widget is nullable (had a type annototation of Optional[Type]), annotation will return the first argument in the Optional clause.

value: T property writable #

Return current value of the widget. This may be interpreted by backends.

__repr__() -> str #

Return representation of widget of instance.

bind(value: T | Callable[[BaseValueWidget], T], call: bool = True) -> None #

Binds value to self.value.

If a value is bound to this widget, then whenever widget.value is accessed, the value provided here will be returned. value can be a callable, in which case value(self) will be returned (i.e. your callback must accept a single parameter, which is this widget instance.).

If you provide a callable and you don't want it to be called (but rather just returned as a callable object, then use call=False when binding your value.

Note: if you need to access the "original" widget.value within your callback, please use widget.get_value() instead of the widget.value property, in order to avoid a RuntimeError.

Parameters:

  • value (Any) –

    The value (or callback) to return when accessing this widget's value.

  • call (bool, default: True ) –

    If value is a callable and call is True, the callback will be called as callback(self) when accessing self.value. If False, the callback will simply be returned as a callable object, by default, True.

get_value() -> T abstractmethod #

Callable version of self.value.

The main API is to use self.value, however, this is here in order to provide an escape hatch if trying to access the widget's value inside of a callback bound to self._bound_value.

set_value(value: Any) -> None abstractmethod #

Normalize and set the value of the widget.

unbind() -> None #

Unbinds any bound values. (see ValueWidget.bind).