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 flash["notice"] = "Successfully created" before redirecting to a display action that can then expose # the flash to its template. Actually, that exposure is automatically done. Example: # # class WeblogController < ActionController::Base # def create # # save post # flash["notice"] = "Successfully created post" # redirect_to :action => "display", :params => { "id" => post.id } # end # # def display # # doesn't need to assign the flash notice to the template, that's done automatically # end # end # # display.rhtml # <% if @flash["notice"] %>
<%= @flash["notice"] %>
<% 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. module Flash def self.append_features(base) #:nodoc: super base.before_filter(:fire_flash) base.after_filter(:clear_flash) end protected # Access the contents of the flash. Use flash["notice"] to read a notice you put there or # flash["notice"] = "hello" to put a new one. def flash #:doc: if @session["flash"].nil? @session["flash"] = {} @session["flashes"] ||= 0 end @session["flash"] end # Can be called by any action that would like to keep the current content of the flash around for one more action. def keep_flash #:doc: @session["flashes"] = 0 end private # Records that the contents of @session["flash"] was flashed to the action def fire_flash if @session["flash"] @session["flashes"] += 1 unless @session["flash"].empty? @assigns["flash"] = @session["flash"] else @assigns["flash"] = {} end end def clear_flash if @session["flash"] && (@session["flashes"].nil? || @session["flashes"] >= 1) @session["flash"] = {} @session["flashes"] = 0 end end end end