module ActionView
module Helpers
module AjaxHelper
# Included for backwards compatibility / RJS functionality
# Rails classes should not be aware of individual JS frameworks
include PrototypeHelper
# Creates a form that will submit using XMLHttpRequest in the background
# instead of the regular reloading POST arrangement and a scope around a
# specific resource that is used as a base for questioning about
# values for the fields.
#
# === Resource
#
# Example:
#
# # Generates:
# #
'.html_safe!)
end
alias_method :form_remote_for, :remote_form_for
# Returns a form tag that will submit using XMLHttpRequest in the
# background instead of the regular reloading POST arrangement. Even
# though it's using JavaScript to serialize the form elements, the form
# submission will work just like a regular submission as viewed by the
# receiving side (all elements available in params). The options for
# specifying the target with :url and defining callbacks is the same as
# +link_to_remote+.
#
# A "fall-through" target for browsers that doesn't do JavaScript can be
# specified with the :action/:method options on :html.
#
# Example:
#
# # Generates:
# #
# #
# <% form_remote_tag :url => '/posts' do -%>
#
<%= submit_tag 'Save' %>
# <% end -%>
def form_remote_tag(options = {}, &block)
html_options = options.delete(:callbacks)
attributes = {}
attributes.merge!(extract_remote_attributes!(options))
attributes.merge!(html_options) if html_options
attributes.merge!(options)
attributes.delete(:builder)
form_tag(attributes.delete(:action) || attributes.delete("data-url"), attributes, &block)
end
# Returns a link to a remote action defined by options[:url]
# (using the url_for format) that's called in the background using
# XMLHttpRequest. The result of that request can then be inserted into a
# DOM object whose id can be specified with options[:update].
# Usually, the result would be a partial prepared by the controller with
# render :partial.
#
# Examples:
#
# # Generates:
# # Delete this post a>
# #
# link_to_remote "Delete this post", :update => "posts",
# :url => { :action => "destroy", :id => post.id }
#
# # Generates:
# #
# #
# # a>
# link_to_remote(image_tag("refresh"), :update => "emails",
# :url => { :action => "list_emails" })
#
# You can override the generated HTML options by specifying a hash in
# options[:html].
#
# # Generates:
# # Delete this post
# #
# link_to_remote "Delete this post", :update => "posts",
# :url => post_url(@post), :method => :delete,
# :html => { :class => "destructive" }
#
# You can also specify a hash for options[:update] to allow for
# easy redirection of output to an other DOM element if a server-side
# error occurs:
#
# Example:
# # Generates:
# # Delete this post
# #
# link_to_remote "Delete this post",
# :url => { :action => "destroy", :id => post.id },
# :update => { :success => "posts", :failure => "error" }
#
# Optionally, you can use the options[:position] parameter to
# influence how the target DOM element is updated. It must be one of
# :before, :top, :bottom, or :after.
#
# The method used is by default POST. You can also specify GET or you
# can simulate PUT or DELETE over POST. All specified with options[:method]
#
# Example:
# # Generates:
# # Destroy
# #
# link_to_remote "Destroy", :url => person_url(:id => person), :method => :delete
#
# By default, these remote requests are processed asynchronous during
# which various JavaScript callbacks can be triggered (for progress
# indicators and the likes). All callbacks get access to the
# request object, which holds the underlying XMLHttpRequest.
#
# To access the server response, use request.responseText, to
# find out the HTTP status, use request.status.
#
# Example:
# # Generates:
# # hello
# #
# word = 'hello'
# link_to_remote word,
# :url => { :action => "undo", :n => word_counter },
# :complete => "undoRequestCompleted(request)"
#
# The callbacks that may be specified are (in order): (deprecated)
#
# :loading:: Called when the remote document is being
# loaded with data by the browser.
# :loaded:: Called when the browser has finished loading
# the remote document.
# :interactive:: Called when the user can interact with the
# remote document, even though it has not
# finished loading.
# :success:: Called when the XMLHttpRequest is completed,
# and the HTTP status code is in the 2XX range.
# :failure:: Called when the XMLHttpRequest is completed,
# and the HTTP status code is not in the 2XX
# range.
# :complete:: Called when the XMLHttpRequest is complete
# (fires after success/failure if they are
# present).
#
# You can further refine :success and :failure by
# adding additional callbacks for specific status codes.
#
# Example:
#
# # Generates:
# # Hello
# #
# link_to_remote word,
# :url => { :action => "action" },
# 404 => "alert('Not found...? Wrong URL...?')",
# :failure => "alert('HTTP Error ' + request.status + '!')"
#
# A status code callback overrides the success/failure handlers if
# present.
#
# If you for some reason or another need synchronous processing (that'll
# block the browser while the request is happening), you can specify
# options[:type] = :synchronous.
#
# You can customize further browser side call logic by passing in
# JavaScript code snippets via some optional parameters. In their order
# of use these are:
#
# :confirm:: Adds confirmation dialog.
# :condition:: Perform remote request conditionally
# by this expression. Use this to
# describe browser-side conditions when
# request should not be initiated.
# :before:: Called before request is initiated.
# :after:: Called immediately after request was
# initiated and before :loading.
# :submit:: Specifies the DOM element ID that's used
# as the parent of the form elements. By
# default this is the current form, but
# it could just as well be the ID of a
# table row or any other DOM element.
# :with:: A JavaScript expression specifying
# the parameters for the XMLHttpRequest.
# Any expressions should return a valid
# URL query string.
#
# Example:
#
# :with => "'name=' + $('name').value"
#
# You can generate a link that uses AJAX in the general case, while
# degrading gracefully to plain link behavior in the absence of
# JavaScript by setting html_options[:href] to an alternate URL.
# Note the extra curly braces around the options hash separate
# it as the second parameter from html_options, the third.
#
# Example:
#
# # Generates:
# # Delete this post
# #
# link_to_remote "Delete this post",
# { :update => "posts", :url => { :action => "destroy", :id => post.id } },
# :href => url_for(:action => "destroy", :id => post.id)
def link_to_remote(name, options, html_options = {})
attributes = {}
attributes.merge!(:rel => "nofollow") if options[:method] && options[:method].downcase == "delete"
attributes.merge!(extract_remote_attributes!(options))
attributes.merge!(extract_confirm_attributes!(options))
attributes.merge!(html_options)
content_tag(:a, name, attributes.merge(:href => "#"))
end
# Creates a button with an onclick event which calls a remote action
# via XMLHttpRequest
# The options for specifying the target with :url
# and defining callbacks is the same as link_to_remote.
def button_to_remote(name, options = {}, html_options = {})
attributes = html_options.merge!(:type => "button", :value => name)
attributes.merge!(extract_confirm_attributes!(options))
attributes.merge!(extract_remote_attributes!(options))
tag(:input, attributes)
end
# Returns a button input tag with the element name of +name+ and a value (i.e., display text) of +value+
# that will submit form using XMLHttpRequest in the background instead of a regular POST request that
# reloads the page.
#
# # Create a button that submits to the create action
# #
# # Generates:
# #
# #
# <%= submit_to_remote 'create_btn', 'Create', :url => { :action => 'create' } %>
#
# # Submit to the remote action update and update the DIV succeed or fail based
# # on the success or failure of the request
# #
# # Generates:
# #
# #
# <%= submit_to_remote 'update_btn', 'Update', :url => { :action => 'update' },
# :update => { :success => "succeed", :failure => "fail" }
#
# options argument is the same as in form_remote_tag.
def submit_to_remote(name, value, options = {})
html_options = options.delete(:html) || {}
html_options.merge!(:name => name, :value => value, :type => "button")
attributes = extract_remote_attributes!(options)
attributes.merge!(html_options)
attributes["data-submit"] = true
attributes.delete("data-remote")
tag(:input, attributes)
end
# Periodically calls the specified url (options[:url]) every
# options[:frequency] seconds (default is 10). Usually used to
# update a specified div (options[:update]) with the results
# of the remote call. The options for specifying the target with :url
# and defining callbacks is the same as link_to_remote.
# Examples:
# # Call get_averages and put its results in 'avg' every 10 seconds
# # Generates:
# # new PeriodicalExecuter(function() {new Ajax.Updater('avg', '/grades/get_averages',
# # {asynchronous:true, evalScripts:true})}, 10)
# periodically_call_remote(:url => { :action => 'get_averages' }, :update => 'avg')
#
# # Call invoice every 10 seconds with the id of the customer
# # If it succeeds, update the invoice DIV; if it fails, update the error DIV
# # Generates:
# # new PeriodicalExecuter(function() {new Ajax.Updater({success:'invoice',failure:'error'},
# # '/testing/invoice/16', {asynchronous:true, evalScripts:true})}, 10)
# periodically_call_remote(:url => { :action => 'invoice', :id => customer.id },
# :update => { :success => "invoice", :failure => "error" }
#
# # Call update every 20 seconds and update the new_block DIV
# # Generates:
# # new PeriodicalExecuter(function() {new Ajax.Updater('news_block', 'update', {asynchronous:true, evalScripts:true})}, 20)
# periodically_call_remote(:url => 'update', :frequency => '20', :update => 'news_block')
#
def periodically_call_remote(options = {})
attributes = extract_observer_attributes!(options)
attributes["data-periodical"] = true
script_decorator(attributes)
end
# Observes the field with the DOM ID specified by +field_id+ and calls a
# callback when its contents have changed. The default callback is an
# Ajax call. By default the value of the observed field is sent as a
# parameter with the Ajax call.
#
# Example:
# # Generates: new Form.Element.Observer('suggest', 0.25, function(element, value) {new Ajax.Updater('suggest',
# # '/testing/find_suggestion', {asynchronous:true, evalScripts:true, parameters:'q=' + value})})
# <%= observe_field :suggest, :url => { :action => :find_suggestion },
# :frequency => 0.25,
# :update => :suggest,
# :with => 'q'
# %>
#
# Required +options+ are either of:
# :url:: +url_for+-style options for the action to call
# when the field has changed.
# :function:: Instead of making a remote call to a URL, you
# can specify javascript code to be called instead.
# Note that the value of this option is used as the
# *body* of the javascript function, a function definition
# with parameters named element and value will be generated for you
# for example:
# observe_field("glass", :frequency => 1, :function => "alert('Element changed')")
# will generate:
# new Form.Element.Observer('glass', 1, function(element, value) {alert('Element changed')})
# The element parameter is the DOM element being observed, and the value is its value at the
# time the observer is triggered.
#
# Additional options are:
# :frequency:: The frequency (in seconds) at which changes to
# this field will be detected. Not setting this
# option at all or to a value equal to or less than
# zero will use event based observation instead of
# time based observation.
# :update:: Specifies the DOM ID of the element whose
# innerHTML should be updated with the
# XMLHttpRequest response text.
# :with:: A JavaScript expression specifying the parameters
# for the XMLHttpRequest. The default is to send the
# key and value of the observed field. Any custom
# expressions should return a valid URL query string.
# The value of the field is stored in the JavaScript
# variable +value+.
#
# Examples
#
# :with => "'my_custom_key=' + value"
# :with => "'person[name]=' + prompt('New name')"
# :with => "Form.Element.serialize('other-field')"
#
# Finally
# :with => 'name'
# is shorthand for
# :with => "'name=' + value"
# This essentially just changes the key of the parameter.
#
# Additionally, you may specify any of the options documented in the
# Common options section at the top of this document.
#
# Example:
#
# # Sends params: {:title => 'Title of the book'} when the book_title input
# # field is changed.
# observe_field 'book_title',
# :url => 'http://example.com/books/edit/1',
# :with => 'title'
#
#
def observe_field(name, options = {})
options[:observed] = name
attributes = extract_observer_attributes!(options)
script_decorator(attributes)
end
# Observes the form with the DOM ID specified by +form_id+ and calls a
# callback when its contents have changed. The default callback is an
# Ajax call. By default all fields of the observed field are sent as
# parameters with the Ajax call.
#
# The +options+ for +observe_form+ are the same as the options for
# +observe_field+. The JavaScript variable +value+ available to the
# :with option is set to the serialized form by default.
def observe_form(name, options = {})
options[:observed] = name
attributes = extract_observer_attributes!(options)
script_decorator(attributes)
end
def script_decorator(options)
attributes = %w(type="application/json")
attributes += options.map{|k, v| k + '="' + v.to_s + '"'}
""
end
private
def extract_confirm_attributes!(options)
attributes = {}
if options && options[:confirm]
attributes["data-confirm"] = options.delete(:confirm)
end
attributes
end
def extract_remote_attributes!(options)
attributes = options.delete(:html) || {}
attributes.merge!(extract_update_attributes!(options))
attributes.merge!(extract_request_attributes!(options))
attributes["data-remote"] = true
attributes
end
def extract_request_attributes!(options)
attributes = {}
attributes["data-method"] = options.delete(:method)
attributes["data-remote-type"] = options.delete(:type)
url_options = options.delete(:url)
url_options = url_options.merge(:escape => false) if url_options.is_a?(Hash)
attributes["data-url"] = escape_javascript(url_for(url_options))
#TODO: Remove all references to prototype - BR
if options.delete(:form)
attributes["data-parameters"] = 'Form.serialize(this)'
elsif submit = options.delete(:submit)
attributes["data-parameters"] = "Form.serialize('#{submit}')"
elsif with = options.delete(:with)
if with !~ /[\{=(.]/
attributes["data-with"] = "'#{with}=' + encodeURIComponent(value)"
else
attributes["data-with"] = with
end
end
purge_unused_attributes!(attributes)
end
def extract_update_attributes!(options)
attributes = {}
update = options.delete(:update)
if update.is_a?(Hash)
attributes["data-update-success"] = update[:success]
attributes["data-update-failure"] = update[:failure]
else
attributes["data-update-success"] = update
end
attributes["data-update-position"] = options.delete(:position)
purge_unused_attributes!(attributes)
end
def extract_observer_attributes!(options)
callback = options.delete(:function)
frequency = options.delete(:frequency)
attributes = extract_remote_attributes!(options)
attributes["data-observe"] = true
attributes["data-observed"] = options.delete(:observed)
attributes["data-onobserve"] = create_js_function(callback, "element", "value") if callback
attributes["data-frequency"] = frequency.to_i if frequency && frequency != 0
attributes.delete("data-remote")
purge_unused_attributes!(attributes)
end
def purge_unused_attributes!(attributes)
attributes.delete_if {|key, value| value.nil? }
attributes
end
def create_js_function(statements, *arguments)
"function(#{arguments.join(", ")}) {#{statements}}"
end
end
# TODO: All evaled goes here per wycat
module AjaxHelperCompat
include AjaxHelper
def link_to_remote(name, options, html_options = {})
set_callbacks(options, html_options)
super
end
def button_to_remote(name, options = {}, html_options = {})
set_callbacks(options, html_options)
super
end
def form_remote_tag(options, &block)
html = {}
set_callbacks(options, html)
options.merge!(:callbacks => html)
super
end
private
def set_callbacks(options, html)
[:uninitialized, :complete, :failure, :success, :interactive, :loaded, :loading].each do |type|
html["data-on#{type}"] = options.delete(type.to_sym)
end
options.each do |option, value|
if option.is_a?(Integer)
html["data-on#{option}"] = options.delete(option)
end
end
end
end
end
end