+++ /dev/null
-module ActionController #:nodoc:
- # The flash provides a way to pass temporary objects between actions. Anything you place in the flash will be exposed
- # to the very next action and then cleared out. This is a great way of doing notices and alerts, such as a create
- # action that sets <tt>flash[:notice] = "Successfully created"</tt> before redirecting to a display action that can
- # then expose the flash to its template. Actually, that exposure is automatically done. Example:
- #
- # class PostsController < ActionController::Base
- # def create
- # # save post
- # flash[:notice] = "Successfully created post"
- # redirect_to posts_path(@post)
- # end
- #
- # def show
- # # doesn't need to assign the flash notice to the template, that's done automatically
- # end
- # end
- #
- # show.html.erb
- # <% if flash[:notice] %>
- # <div class="notice"><%= flash[:notice] %></div>
- # <% end %>
- #
- # This example just places a string in the flash, but you can put any object in there. And of course, you can put as
- # many as you like at a time too. Just remember: They'll be gone by the time the next action has been performed.
- #
- # See docs on the FlashHash class for more details about the flash.
- module Flash
- def self.included(base)
- base.class_eval do
- include InstanceMethods
- alias_method_chain :perform_action, :flash
- alias_method_chain :reset_session, :flash
- end
- end
-
- class FlashNow #:nodoc:
- def initialize(flash)
- @flash = flash
- end
-
- def []=(k, v)
- @flash[k] = v
- @flash.discard(k)
- v
- end
-
- def [](k)
- @flash[k]
- end
- end
-
- class FlashHash < Hash
- def initialize #:nodoc:
- super
- @used = {}
- end
-
- def []=(k, v) #:nodoc:
- keep(k)
- super
- end
-
- def update(h) #:nodoc:
- h.keys.each { |k| keep(k) }
- super
- end
-
- alias :merge! :update
-
- def replace(h) #:nodoc:
- @used = {}
- super
- end
-
- # Sets a flash that will not be available to the next action, only to the current.
- #
- # flash.now[:message] = "Hello current action"
- #
- # This method enables you to use the flash as a central messaging system in your app.
- # When you need to pass an object to the next action, you use the standard flash assign (<tt>[]=</tt>).
- # When you need to pass an object to the current action, you use <tt>now</tt>, and your object will
- # vanish when the current action is done.
- #
- # Entries set via <tt>now</tt> are accessed the same way as standard entries: <tt>flash['my-key']</tt>.
- def now
- FlashNow.new(self)
- end
-
- # Keeps either the entire current flash or a specific flash entry available for the next action:
- #
- # flash.keep # keeps the entire flash
- # flash.keep(:notice) # keeps only the "notice" entry, the rest of the flash is discarded
- def keep(k = nil)
- use(k, false)
- end
-
- # Marks the entire flash or a single flash entry to be discarded by the end of the current action:
- #
- # flash.discard # discard the entire flash at the end of the current action
- # flash.discard(:warning) # discard only the "warning" entry at the end of the current action
- def discard(k = nil)
- use(k)
- end
-
- # Mark for removal entries that were kept, and delete unkept ones.
- #
- # This method is called automatically by filters, so you generally don't need to care about it.
- def sweep #:nodoc:
- keys.each do |k|
- unless @used[k]
- use(k)
- else
- delete(k)
- @used.delete(k)
- end
- end
-
- # clean up after keys that could have been left over by calling reject! or shift on the flash
- (@used.keys - keys).each{ |k| @used.delete(k) }
- end
-
- private
- # Used internally by the <tt>keep</tt> and <tt>discard</tt> methods
- # use() # marks the entire flash as used
- # use('msg') # marks the "msg" entry as used
- # use(nil, false) # marks the entire flash as unused (keeps it around for one more action)
- # use('msg', false) # marks the "msg" entry as unused (keeps it around for one more action)
- def use(k=nil, v=true)
- unless k.nil?
- @used[k] = v
- else
- keys.each{ |key| use(key, v) }
- end
- end
- end
-
- module InstanceMethods #:nodoc:
- protected
- def perform_action_with_flash
- perform_action_without_flash
- remove_instance_variable(:@_flash) if defined? @_flash
- end
-
- def reset_session_with_flash
- reset_session_without_flash
- remove_instance_variable(:@_flash) if defined? @_flash
- end
-
- # Access the contents of the flash. Use <tt>flash["notice"]</tt> to
- # read a notice you put there or <tt>flash["notice"] = "hello"</tt>
- # to put a new one.
- def flash #:doc:
- unless defined? @_flash
- @_flash = session["flash"] ||= FlashHash.new
- @_flash.sweep
- end
-
- @_flash
- end
- end
- end
-end
projects / feedcatcher.git / blobdiff