bootstack.Button#

class bootstack.Button(text='', *, on_click=None, accent=None, variant='default', icon=None, icon_only=False, icon_position='left', image=None, width=None, textsignal=None, density=None, disabled=False, localize=None, parent=None, **kwargs)#

Bases: IconProperty, ImageProperty, PublicWidgetBase

A clickable action trigger.

The button text is the first positional argument. All styling and behavior options are keyword-only.

Parameters:

  • text (str) – Text displayed on the button.

  • on_click (Callable[[], Any] | None) – Called with no arguments when the button is clicked. Equivalent to subscribing to the 'click' event.

  • accent (AccentToken | str | None) – Color intent token. Defaults to the theme’s default button color.

  • variant (ButtonVariant) – Visual weight token. Default 'solid'.

  • icon (str | IconSpec | None) – Bootstrap Icons name (e.g. 'save', 'trash') — see the full catalog at https://icons.getbootstrap.com — or an IconSpec mapping ({'name', 'size', 'color'}) for control over size and color.

  • icon_only (bool) – If True, show only the icon with no text. Inferred automatically when icon= is set and no text is provided. Set meaningful text anyway for accessibility.

  • icon_position (IconPosition) – Position of the icon or image relative to the text. Default 'left'.

  • image (Any) – An Image handle (from bootstack.images) to display on the button, for custom artwork rather than a Bootstrap Icon name. Also accepts a get_icon result.

  • width (int | None) – Button width in character units. Useful for making a row of buttons uniform width (e.g. width=10).

  • textsignal (Signal[str] | None) – Reactive Signal[str] bound to the button text. Updates automatically when the signal changes.

  • density (WidgetDensity | None) – Padding density.

  • disabled (bool) – If True, the button is non-interactive and visually dimmed.

  • localize (LocalizeMode | None) – Whether the text is translated through the catalog — True, False, or 'auto'. Defaults to the app’s localize_mode. Set False to keep a proper noun or identifier untranslated.

  • parent (Any) – Explicit parent widget. If omitted, the current context-stack container is used.

  • **kwargs (Any) – Layout placement options applied by the parent container — fill, expand, anchor, margin, row, column, sticky. See Layout & Spacing.

property disabled: bool#

Whether the button is non-interactive.

property icon: str | IconSpec | None#

The icon shown on the widget, or None if none is set.

A Bootstrap Icons name, or an IconSpec mapping ({'name', 'size', 'color'}) for control over size and color.

property image: Any#

The displayed image handle, or None.

Assigning an Image (from bootstack.images) updates the picture in place — no rebuild — which avoids the flicker of recreating the widget.

property is_attached: bool#

Whether the widget is currently placed in its layout.

True while the widget occupies space in its parent; False after detach (or before it has ever been placed). A detached widget keeps its state and can be returned to the layout with attach.

property schedule: Schedule#

Scheduler tied to this widget’s lifetime.

All jobs are automatically cancelled when the widget is destroyed. First access creates the Schedule instance; subsequent accesses return the same instance.

Usage:

self.schedule.delay(500, callback)
self.schedule.every(1000, tick)
job = self.schedule.idle(refresh)
job.cancel()
property text: str#

The button’s text.

attach(**kwargs)#

Return a detached widget to its layout, optionally moving it.

With no arguments, restores the widget to exactly where detach took it from. Any layout kwargs accepted by the original placement (e.g. fill, expand, anchor, sticky, margin) override the stored options. For stacked widgets, index= sets the position among the currently attached siblings (or pass an explicit before=/after= sibling); without one, the snapshotted position is used.

Calling attach on a widget that is already attached moves it (the kwargs are re-applied). Fires on_attach.

Parameters:

**kwargs (Any) – Layout placement options to override for this placement.

Raises:

ParentResolutionError – If the widget was never placed in a layout.

click()#

Programmatically invoke the button’s command.

destroy()#

Destroy the widget and release the resources it holds.

Removes the widget from its parent, destroys its children, and cancels any pending or repeating jobs on its schedule. After this the widget must not be used again. Destroying a container destroys everything inside it.

detach()#

Remove the widget from its layout without destroying it.

The widget stops occupying space but keeps its state, children, and event bindings, ready to be returned with attach. The current position is snapshotted so a plain attach() restores it exactly — for stacked siblings this is the index among the currently attached siblings, so detaching other siblings first shifts that index.

Calling detach on a widget that is already detached, or one that was never placed in a layout, does nothing. Fires on_detach.

emit(event, *, data=None)#

Fire a named event on this widget, as if it produced the event itself.

This is how a composite widget surfaces high-level activity to its listeners, and the generic counterpart to the on_*() shorthands for firing events that have no dedicated method.

Parameters:

  • event (str) – The event name, unprefixed — the same name you pass to on() or an on_<event>() shorthand (e.g. 'change', 'select').

  • data (Any) – The payload delivered to handlers. For a data-carrying event, pass the matching payload dataclass from bootstack.events — the same object an on_<event>() handler receives. Leave as None for native events (click, hover, focus, …), which carry no payload.

Example

widget.emit("change", data=bs.events.ChangeEvent(value=new_value))
get_clipboard()#

Return the current text contents of the system clipboard.

Returns:

The clipboard text, or an empty string when the clipboard is empty or holds non-text data.

Return type:

str

on(event, handler=None)#

Bind handler to event, or return a composable Stream.

With a handler — binds immediately and returns a Subscription:

sub = widget.on("change", handler)
sub.cancel()

Without a handler — returns a Stream for operator chaining. The Tk binding is created lazily when .listen() is called:

sub = widget.on("change").debounce(300).listen(handler)
sub.cancel()
Parameters:

  • event (str) – Event name (e.g. "change", "click").

  • handler (Callable[[Any], Any] | None) – Optional callback. If omitted, a Stream is returned.

Returns:

Subscription when a handler is provided; Stream otherwise.

Return type:

Stream | Subscription

on_attach(handler=None)#

Register a callback fired when the widget enters the layout.

Fires each time the widget becomes visible in its parent — on initial placement and on every attach. Pair it with on_detach to keep per-visibility resources (timers, observers) tied to the widget’s presence on screen. The handler receives a curated Event.

Parameters:

handler (Callable[[Event], Any] | None) – Called when the widget is attached. Omit to get a composable Stream.

Returns:

A cancellable Subscription when a handler is given, otherwise a Stream.

Return type:

Stream | Subscription

on_click() → Stream#
on_click(handler: Callable[[Event], Any]) → Subscription

Register a callback for button click events.

Called with no handler, returns a composable Stream. Called with a handler, binds it immediately and returns a Subscription.

For a simple click action prefer the on_click= constructor argument, which takes a no-argument callback. This method’s handler receives the curated Event (pointer position, modifier keys), consistent with every other on_* shorthand.

Parameters:

handler (Callable[[Event], Any] | None) – Called with the click Event (pointer position, modifier keys). Omit to get a composable Stream.

Returns:

A cancellable Subscription when a handler is given, otherwise a Stream.

Return type:

Stream | Subscription

on_destroy(handler=None)#

Register a callback fired when the widget is destroyed.

Fires once, as the widget is torn down — the place to release resources the widget owns that aren’t cleaned up automatically (file handles, observers, external subscriptions). The handler receives a curated Event.

Parameters:

handler (Callable[[Event], Any] | None) – Called as the widget is destroyed. Omit to get a composable Stream.

Returns:

A cancellable Subscription when a handler is given, otherwise a Stream.

Return type:

Stream | Subscription

on_detach(handler=None)#

Register a callback fired when the widget leaves the layout.

Fires each time the widget stops occupying space in its parent — on detach and when an ancestor hides it. Pair it with on_attach to release per-visibility resources. The handler receives a curated Event.

Parameters:

handler (Callable[[Event], Any] | None) – Called when the widget is detached. Omit to get a composable Stream.

Returns:

A cancellable Subscription when a handler is given, otherwise a Stream.

Return type:

Stream | Subscription

set_clipboard(text)#

Replace the system clipboard contents with text.

Parameters:

text (str) – The text to place on the clipboard.