Module: SKUI::Events

Included in:
Base
Defined in:
src/SKUI/events.rb

Overview

Since:

  • 1.0.0

Defined Under Namespace

Modules: EventDefinitions

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.included(including_module) ⇒ Object

In order to create an class instance variable for each control type that holds a list of the valid events for the control this

Adapted from: www.railstips.org/blog/archives/2006/11/18/class-and-instance-variables-in-ruby/ www.railstips.org/blog/archives/2009/05/15/include-vs-extend-in-ruby/

Parameters:

  • including_module (Module)

Since:

  • 1.0.0



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# File 'src/SKUI/events.rb', line 19

def self.included( including_module )
  # Hash table of valid events for the class.
  # >   Key: (Symbol)
  # > Value: (Symbol)
  including_module.instance_variable_set( :@control_events, {} )
  including_module.extend( EventDefinitions )
end

Instance Method Details

#add_event_handler(event, &block) ⇒ nil Also known as: on

Adds an event handler to the stack. Each event can have multiple handlers.

Parameters:

  • event (Symbol)
  • block (Proc)

Returns:

  • (nil)

Since:

  • 1.0.0



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# File 'src/SKUI/events.rb', line 42

def add_event_handler( event, &block )
  unless self.class.has_event?( event )
    raise( ArgumentError, "Event #{event} not defined for #{self.class}" )
  end
  unless block_given?
    raise( ArgumentError, 'No block given.' )
  end
  @events[event] ||= []
  @events[event] << block
  nil
end

#initialize ⇒ Object

Since:

  • 1.0.0



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# File 'src/SKUI/events.rb', line 28

def initialize
  super()
  # Hash with Symbols for keys idenitfying the event.
  # Each event is an array of Proc's.
  @events = {}
end

#release_events ⇒ nil

Detaches all event handlers. Useful when one want to allow the objects to be garbage collected.

Returns:

  • (nil)

Since:

  • 1.0.0



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# File 'src/SKUI/events.rb', line 60

def release_events
  @events.clear
  nil
end

#trigger_event(event, *args) ⇒ Boolean

Triggers the given event. All attached procs for the given event will be called. If any event handler raises an error the remaining handlers will not be executed.

Parameters:

  • event (Symbol)
  • args (Array) —

    Set of arguments to be passed to the called procs.

Returns:

  • (Boolean)

Since:

  • 1.0.0



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# File 'src/SKUI/events.rb', line 74

def trigger_event( event, *args )
  #Debug.puts( "#{self.class}.trigger_event(#{event.to_s})" )
  #Debug.puts( args.inspect )
  if @events.key?( event )
    @events[event].each { |proc|
      # Add self to argument list so the called event can get the handle for
      # the control triggering it.
      if args.empty?
        proc.call( self )
      else
        args.unshift( self )
        proc.call( *args )
      end
    }
    true
  else
    false
  end
end