Globally accessible attribute in UIViewController instances

Question

In my RubyMotion app I would like to have a attribute, called access_token, accessible in every UIViewController instance.

All my controllers are either a subclass of TableController or AppController.

I tried creating an attr_accessor for TableController and AppController, though the problem is that assigning a new value will not be set for TableController or AppController at the same time.

How could I achieve this?

Answer 1

I personally use class variables for things like this, since iOS apps are not multi-user. Taking advantage of the fact that inherited classes share class variables, @@access_token will have the same value for all of your UIViewController subclasses (or your own subclass if you prefer).

I have something similar to this:

# Reopen and extend
class UIViewController # Actually I prefer UIViewController.class_eval do
  @@access_token = nil # This will have the same value for all UIViewController children

  def self.access_token=(value)
    @@access_token = value
  end

  def self.access_token
    @@access_token
  end
end

In reality, I would build a class that holds properties including and in addition to the token.