Module MUES::Event::Handler
In: lib/mues/events.rb  (CVS)

A default event handler mixin module. Including this module adds methods to the including class/module that are useful for an object which wishes to handle one or more event types.

Methods

handleEvent   registerHandlerForEvents   unregisterHandlerForEvents  

Included Modules

MUES::TypeCheckFunctions MUES::Debuggable

Public Instance methods

handleEvent( event )

Event dispatcher method. This method does dynamic dispatch to class-specific event handler methods in the class that mixes it in. It will look for a method called handle<eventClass>(), where eventClass is the class of the event to handle. If no explicit handler is found, each of the event‘s superclasses is tried as well. If no handler is defined for any of the events, it tries to call handleAnyEvent(). If no handler is found, a MUES::UnhandledEventError is raised.

[Source]

# File lib/mues/events.rb, line 83
            def handleEvent( event )
                raise TypeError, "argument (#{event.to_s}) is not an event" unless
                    event.is_a?( Event )
                debugMsg( 1, "Handling a #{event.class.name} event." )

                methodName = ''

                # Search the event's class heirarchy for Event subclasses, and
                # look up handler methods based on the class name
                event.class.ancestors.find_all {|klass| 
                    klass < Event
                }.each {|klass|
                    eventType = klass.name.sub( /MUES::/, '' )
                    debugMsg( 2, "Checking for a handle#{eventType} method..." )
                    methodName = 'handle%s' % eventType
                    if self.respond_to?( methodName )
                        debugMsg( 2, "   found #{methodName}." )
                        return send( methodName, event )
                    end
                }

                ### Now call the default handler if it defines one
                debugMsg( 1, "Unable to handle the #{event.class.name}. Invoking the handleEvent method." )
                return self.handleAnyEvent( event ) if
                    self.respond_to?( :handleAnyEvent )

                raise UnhandledEventError, "No handler defined for #{event.class.name}s"
            end
registerHandlerForEvents( handlerObject, *eventClasses )

Register handlerObject to receive events of the specified eventClasses or any of their derivatives. See the docs for MUES::Event for how to handle events.

[Source]

# File lib/mues/events.rb, line 116
            def registerHandlerForEvents( handlerObject, *eventClasses )
                checkResponse( handlerObject, "handleEvent" )

                eventClasses.each do |eventClass|
                    eventClass.registerHandlers( handlerObject )
                end
            end
unregisterHandlerForEvents( handlerObject, *eventClasses )

Unregister handlerObject as a handler for the specified eventClasses, or all event classes if no classes are specified.

[Source]

# File lib/mues/events.rb, line 128
            def unregisterHandlerForEvents( handlerObject, *eventClasses )
                eventClasses = MUES::Event::getEventClasses if eventClasses.empty?
                eventClasses.each {|eventClass|
                    eventClass.unregisterHandlers( handlerObject )
                }
            end

[Validate]