Class Event

packages/reflex-base/src/reflex_base/event/__init__.py:78–168

An event that describes any state change in the app. Attributes: name: The event name. router_data: The routing data where event occurred. payload: The event payload.

    frozen=True,
)
class Event:
    """An event that describes any state change in the app.

    Attributes:
        name: The event name.
        router_data: The routing data where event occurred.
        payload: The event payload.
    """

    name: str

    router_data: dict[str, Any] = dataclasses.field(default_factory=dict)

    payload: dict[str, Any] = dataclasses.field(default_factory=dict)

    @property
    def state_cls(self) -> "type[BaseState]":
        """The state class for the event."""
        from reflex_base.registry import RegistrationContext

        substate_name = self.name.rpartition(".")[0]
        return RegistrationContext.get().base_states[substate_name]

    @classmethod
    def from_event_type(
        cls,
        events: "IndividualEventType | list[IndividualEventType] | None",
        *,
        router_data: dict[str, Any] | None = None,
    ) -> "list[Event]":
        """Create a list of Events from event-like objects.

        Args:
            events: The event-like objects to create Events from.
            router_data: The routing data for the events.

        Returns:
            A list of Events created from the event-like objects.
        """
        # If the event handler returns nothing, return an empty list.
        if events is None:
            return []

        # If the handler returns a single event, wrap it in a list.
        if not isinstance(events, list):
            events = [events]

        # Fix the events created by the handler.
        out = []
        for e in events:
            if callable(e) and getattr(e, "__name__", "") == "<lambda>":
                # A lambda was returned, assume the user wants to call it with no args.
                e = e()
            if isinstance(e, Event):
                # If the event is already an event, append it to the list.
                if router_data is not None and e.router_data != router_data:
                    out.append(
                        dataclasses.replace(e, router_data=e.router_data | router_data)