Class: Wee::Component

Inherits:
Presenter show all
Includes:
CallAnswerMixin, DecorationMixin
Defined in:
lib/wee/component.rb

Overview

The base class of all components. You should at least overwrite method #render in your own subclasses.

Instance Attribute Summary

Attributes included from DecorationMixin

#decoration

Instance Method Summary collapse

Methods included from DecorationMixin

#add_decoration, #each_decoration, #remove_decoration, #remove_decoration_if

Methods inherited from Presenter

#render_on, #renderer_class

Constructor Details

#initialize ⇒ Component

Initializes a newly created component.

Call this method from your own components’ initialize method using super, before setting up anything else!



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# File 'lib/wee/component.rb', line 19

def initialize() # :notnew:
  @decoration = self
  @children = nil
end

Instance Method Details

#backtrack(state) ⇒ Object

Take snapshots of objects that should correctly be backtracked.

Backtracking means that you can go back in time of the components’ state. Therefore it is neccessary to take snapshots of those objects that want to participate in backtracking. Taking snapshots of the whole component tree would be too expensive and unflexible. Note that methods take_snapshot and restore_snapshot are called for those objects to take the snapshot (they behave like marshal_dump and marshal_load). Overwrite them if you want to define special behaviour.

For example if you dynamically add children to your component, you might want to backtrack the children array:

def backtrack(state)
  super
  backtrack_children(state)
end

By default only the decoration chain is backtracked. This is required to correctly backtrack called components. To disable backtracking of the decorations, change method Component#backtrack_decoration to a no-operation:

def backtrack_decoration(state)
  # nothing here
end
state

An object of class State



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# File 'lib/wee/component.rb', line 88

def backtrack(state)
  backtrack_decoration(state)
  each_child do |child|
    child.decoration.backtrack(state)
  end
end

#process_callbacks(callbacks) ⇒ Object

Process and invoke all callbacks specified for this component and all of it’s child components.



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# File 'lib/wee/component.rb', line 40

def process_callbacks(callbacks)
  callbacks.input_callbacks.each_triggered(self) do |callback, value|
    callback.call(value)
  end

  # process callbacks of all children
  each_child do |child|
    child.decoration.process_callbacks(callbacks)
  end

  callbacks.action_callbacks.each_triggered(self) do |callback, value|
    callback.call
    session.send_response(nil) # prematurely end callback processing
  end
end

#render(r) ⇒ Object

This method renders the content of the component.

OVERWRITE this method in your own component classes to implement the view. By default this method does nothing!

r

An instance of class renderer_class()



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# File 'lib/wee/component.rb', line 33

def render(r)
end