Teek API Documentation

Teek::UI::EventBus Class

In-process publish/subscribe for decoupled app events (:item_selected, :theme_changed) - not Tk events, complementary to Handle#on_click/Handle#on_key. Reach for this only when a direct handle or a shared reactive Var would couple things that should stay decoupled.

Owned by one Session (ui.on/ui.emit/ui.off) - two separate Teek::UI.app instances in the same process never share a bus. Pure Ruby, no Tk/interpreter involved, so it works before realize too.

Inherits: Object

Instance Methods ↑

emit(event, *args, **kwargs)

Emit a named event to every current subscriber, in subscription order.

Parameters
  • event Symbol
  • args Array — forwarded to each subscriber
  • kwargs Hash — forwarded to each subscriber

Returns void

View source ▼ 
def emit(event, *args, **kwargs)
  if kwargs.empty?
    @listeners[event].each { |listener| listener.call(*args) }
  else
    @listeners[event].each { |listener| listener.call(*args, **kwargs) }
  end
  nil
end
GitHub

initialize

Returns EventBus — a new instance of EventBus

@api private

View source ▼ 
def initialize
  @listeners = Hash.new { |h, k| h[k] = [] }
end
GitHub

off(event, block)

Unsubscribe a specific listener.

Parameters
  • event Symbol
  • block Proc — the block #on returned

Returns void

View source ▼ 
def off(event, block)
  @listeners[event].delete(block)
  nil
end
GitHub

on(event, &block)

Subscribe to a named event.

Parameters
  • event Symbol

Returns Proc — the block, to pass to a later #off

@yield the subscriber, called with whatever #emit was given

View source ▼ 
def on(event, &block)
  @listeners[event] << block
  block
end
GitHub