module ActionView
module Helpers
# Provides a set of methods for making easy links and getting urls that depend on the controller and action. This means that
# you can use the same format for links in the views that you do in the controller. The different methods are even named
# synchronously, so link_to uses that same url as is generated by url_for, which again is the same url used for
# redirection in redirect_to.
module UrlHelper
# Returns the URL for the set of +options+ provided. See the valid options in link:classes/ActionController/Base.html#M000021
def url_for(options = {}, *parameters_for_method_reference)
if Hash === options then options = { :only_path => true }.merge(options) end
@controller.send(:url_for, options, *parameters_for_method_reference)
end
# Creates a link tag of the given +name+ using an URL created by the set of +options+. See the valid options in
# link:classes/ActionController/Base.html#M000021. It's also possible to pass a string instead of an options hash to
# get a link tag that just points without consideration. The html_options have a special feature for creating javascript
# confirm alerts where if you pass :confirm => 'Are you sure?', the link will be guarded with a JS popup asking that question.
# If the user accepts, the link is processed, otherwise not.
def link_to(name, options = {}, html_options = {}, *parameters_for_method_reference)
convert_confirm_option_to_javascript!(html_options) unless html_options.nil?
if options.is_a?(String)
content_tag "a", name, (html_options || {}).merge({ "href" => options })
else
content_tag("a", name, (html_options || {}).merge({ "href" => url_for(options, *parameters_for_method_reference) }))
end
end
# Creates a link tag to the image residing at the +src+ using an URL created by the set of +options+. See the valid options in
# link:classes/ActionController/Base.html#M000021. It's also possible to pass a string instead of an options hash to
# get a link tag that just points without consideration. The <tt>html_options</tt> works jointly for the image and ahref tag by
# letting the following special values enter the options on the image and the rest goes to the ahref:
#
# * <tt>alt</tt> - If no alt text is given, the file name part of the +src+ is used (capitalized and without the extension)
# * <tt>size</tt> - Supplied as "XxY", so "30x45" becomes width="30" and height="45"
# * <tt>border</tt> - Is set to 0 by default
# * <tt>align</tt> - Sets the alignment, no special features
#
# The +src+ can be supplied as a...
# * full path, like "/my_images/image.gif"
# * file name, like "rss.gif", that gets expanded to "/images/rss.gif"
# * file name without extension, like "logo", that gets expanded to "/images/logo.png"
def link_to_image(src, options = {}, html_options = {}, *parameters_for_method_reference)
image_options = { "src" => src.include?("/") ? src : "/images/#{src}" }
image_options["src"] = image_options["src"] + ".png" unless image_options["src"].include?(".")
if html_options["alt"]
image_options["alt"] = html_options["alt"]
html_options.delete "alt"
else
image_options["alt"] = src.split("/").last.split(".").first.capitalize
end
if html_options["size"]
image_options["width"], image_options["height"] = html_options["size"].split("x")
html_options.delete "size"
end
if html_options["border"]
image_options["border"] = html_options["border"]
html_options.delete "border"
else
image_options["border"] = "0"
end
if html_options["align"]
image_options["align"] = html_options["align"]
html_options.delete "align"
end
link_to(tag("img", image_options), options, html_options, *parameters_for_method_reference)
end
# Creates a link tag of the given +name+ using an URL created by the set of +options+, unless the current
# controller, action, and id are the same as the link's, in which case only the name is returned (or the
# given block is yielded, if one exists). This is useful for creating link bars where you don't want to link
# to the page currently being viewed.
def link_to_unless_current(name, options = {}, html_options = {}, *parameters_for_method_reference)
assume_current_url_options!(options)
if destination_equal_to_current(options)
block_given? ?
yield(name, options, html_options, *parameters_for_method_reference) :
html_escape(name)
else
link_to name, options, html_options, *parameters_for_method_reference
end
end
# Creates a link tag for starting an email to the specified <tt>email_address</tt>, which is also used as the name of the
# link unless +name+ is specified. Additional HTML options, such as class or id, can be passed in the <tt>html_options</tt> hash.
def mail_to(email_address, name = nil, html_options = {})
content_tag "a", name || email_address, html_options.merge({ "href" => "mailto:#{email_address}" })
end
private
def destination_equal_to_current(options)
params_without_location = @params.reject { |key, value| %w( controller action id ).include?(key) }
options[:action] == @params['action'] &&
options[:id] == @params['id'] &&
options[:controller] == @params['controller'] &&
(options.has_key?(:params) ? params_without_location == options[:params] : true)
end
def assume_current_url_options!(options)
if options[:controller].nil?
options[:controller] = @params['controller']
if options[:action].nil?
options[:action] = @params['action']
if options[:id].nil? then options[:id] ||= @params['id'] end
end
end
end
def convert_confirm_option_to_javascript!(html_options)
if html_options.include?(:confirm)
html_options["onclick"] = "return confirm('#{html_options[:confirm]}');"
html_options.delete(:confirm)
end
end
end
end
end
