from typing import Any, Callable, Optional, cast from typing_extensions import Self from ...binding import BindableProperty, bind, bind_from, bind_to from ...element import Element from ...events import Handler, ValueChangeEventArguments, handle_event class SelectableElement(Element): selected = BindableProperty( on_change=lambda sender, selected: cast(Self, sender)._handle_selection_change(selected)) # pylint: disable=protected-access def __init__(self, *, selectable: bool, selected: bool, on_selection_change: Optional[Handler[ValueChangeEventArguments]] = None, **kwargs: Any) -> None: super().__init__(**kwargs) if not selectable: return self._props['selectable'] = selectable self.selected = selected self._props['selected'] = selected self.set_selected(selected) self.on('update:selected', lambda e: self.set_selected(e.args)) self._selection_change_handlers: list[Handler[ValueChangeEventArguments]] = [] if on_selection_change: self.on_selection_change(on_selection_change) def on_selection_change(self, callback: Handler[ValueChangeEventArguments]) -> Self: """Add a callback to be invoked when the selection state changes.""" self._selection_change_handlers.append(callback) return self def bind_selected_to(self, target_object: Any, target_name: str = 'selected', forward: Optional[Callable[[Any], Any]] = None, *, strict: Optional[bool] = None, ) -> Self: """Bind the selection state of this element to the target object's target_name property. The binding works one way only, from this element to the target. The update happens immediately and whenever a value changes. :param target_object: The object to bind to. :param target_name: The name of the property to bind to. :param forward: A function to apply to the value before applying it to the target (default: identity). :param strict: Whether to check (and raise) if the target object has the specified property (default: None, performs a check if the object is not a dictionary, *added in version 3.0.0*). """ bind_to(self, 'selected', target_object, target_name, forward, self_strict=False, other_strict=strict) return self def bind_selected_from(self, target_object: Any, target_name: str = 'selected', backward: Optional[Callable[[Any], Any]] = None, *, strict: Optional[bool] = None, ) -> Self: """Bind the selection state of this element from the target object's target_name property. The binding works one way only, from the target to this element. The update happens immediately and whenever a value changes. :param target_object: The object to bind from. :param target_name: The name of the property to bind from. :param backward: A function to apply to the value before applying it to this element (default: identity). :param strict: Whether to check (and raise) if the target object has the specified property (default: None, performs a check if the object is not a dictionary, *added in version 3.0.0*). """ bind_from(self, 'selected', target_object, target_name, backward, self_strict=False, other_strict=strict) return self def bind_selected(self, target_object: Any, target_name: str = 'selected', *, forward: Optional[Callable[[Any], Any]] = None, backward: Optional[Callable[[Any], Any]] = None, strict: Optional[bool] = None, ) -> Self: """Bind the selection state of this element to the target object's target_name property. The binding works both ways, from this element to the target and from the target to this element. The update happens immediately and whenever a value changes. The backward binding takes precedence for the initial synchronization. :param target_object: The object to bind to. :param target_name: The name of the property to bind to. :param forward: A function to apply to the value before applying it to the target (default: identity). :param backward: A function to apply to the value before applying it to this element (default: identity). :param strict: Whether to check (and raise) if the target object has the specified property (default: None, performs a check if the object is not a dictionary, *added in version 3.0.0*). """ bind(self, 'selected', target_object, target_name, forward=forward, backward=backward, self_strict=False, other_strict=strict) return self def set_selected(self, selected: bool) -> None: """Set the selection state of this element. :param selected: The new selection state. """ self.selected = selected def _handle_selection_change(self, selected: bool) -> None: """Called when the selection state of this element changes. :param selected: The new selection state. """ previous_value = self._props.get('selected') self._props['selected'] = selected args = ValueChangeEventArguments(sender=self, client=self.client, value=selected, previous_value=previous_value) for handler in self._selection_change_handlers: handle_event(handler, args)