acmecse.helpers.EventManager.EventManager

class documentation

class EventManager:

Known subclasses: acmecse.runtime.EventManager.EventManager

Base class for an event manager. This class manages events and event handlers. It is implememted as a Singleton, so there is only one instance of the event manager in the whole application.

Event topics are added as new methods to an EventManager instance. Events can be raised by calling those new methods.

Example

manager.addEvent("anEvent"): Add new Event topic anEvent to manager.
manager.addHandler(manager.anEvent, handlerFunction): Add an event handler for the anEvent Event.
manager.anEvent(anArg): Raise the anEvent Event with an anArg argument.

Method	`__getattr__`	Dynamically create and return an `Event` instance when accessing an attribute that does not exist.
Method	`addEvent`	Create and add a new `Event`.
Method	`addHandler`	Add a new event handler to an `Event` or to a list of `Event` instance.
Method	`hasEvent`	Check whether an `Event` instance exists.
Method	`hasHandler`	Test whether one or more events have a specific handler assigned.
Method	`removeAllEvents`	Remove all registered `Event` instances.
Method	`removeEvent`	Remove an `Event` instance by its name.
Method	`removeHandler`	Remove an event handler from an `Event` instance or a list of `Event` instances.

def __getattr__(self, name: str) -> Event: ¶

Dynamically create and return an Event instance when accessing an attribute that does not exist.

Parameters
name:`str`	The name of the attribute to access, which will be used as the name of the `Event` instance.

Returns
`Event`	The created `Event` instance.

Raises
`AttributeError`	If the attribute name starts with an underscore (to prevent access to private attributes).

def addEvent(self, name: str, runInBackground: bool | None = True) -> Event: ¶

Create and add a new Event.

Parameters
name:`str`	Name of the `Event`.
runInBackground:`bool \| None`	(optional, default = True) Execute the callbacks in a thread.

Returns
`Event`	The created `Event`.

def addHandler(self, event: Event | list[Event], func: Callable): ¶

Add a new event handler to an Event or to a list of Event instance.

Parameters
event:`Event \| list[Event]`	Either a single `Event` instance or a list of `Event` instances.
func:`Callable`	The function callback to call when the event is raised.

def hasEvent(self, name: str) -> bool: ¶

Check whether an Event instance exists.

Parameters
name:`str`	Name of the `Event` instance to check.

Returns
`bool`	True if an `Event` instance with name exists.

def hasHandler(self, event: Event | list[Event], func: Callable) -> bool: ¶

Test whether one or more events have a specific handler assigned.

Parameters
event:`Event \| list[Event]`	Either a single `Event` or a list of `Event` instances.
func:`Callable`	The function callback to call when the event is raised.

Returns
`bool`	True if func is a registered event handler.

def removeAllEvents(self): ¶

Remove all registered Event instances.

def removeEvent(self, name: str): ¶

Remove an Event instance by its name.

Parameters
name:`str`	The name of the `Event` instance to remove.

def removeHandler(self, event: Event | list[Event], func: Callable): ¶

Remove an event handler from an Event instance or a list of Event instances.

Parameters
event:`Event \| list[Event]`	Either a single `Event` or a list of `Event` instances.
func:`Callable`	The function callback to remove from the `Event` instance(s).