require 'cgi' require File.dirname(__FILE__) + '/date_helper' require File.dirname(__FILE__) + '/tag_helper' module ActionView module Helpers # Provides a set of methods for working with forms and especially forms related to objects assigned to the template. # The following is an example of a complete form for a person object that works for both creates and updates built # with all the form helpers. The @person object was assigned by an action on the controller: #
# Name: # <%= text_field "person", "name", "size" => 20 %> # # Password: # <%= password_field "person", "password", "maxsize" => 20 %> # # Single?: # <%= check_box "person", "single" %> # # Description: # <%= text_area "person", "description", "cols" => 20 %> # # #
# # ...is compiled to: # #
# Name: # # # Password: # # # Single?: # # # Description: # # # #
# # If the object name contains square brackets the id for the object will be inserted. Example: # # <%= text_field "person[]", "name" %> # # ...becomes: # # # # If the helper is being used to generate a repetitive sequence of similar form elements, for example in a partial # used by render_collection_of_partials, the "index" option may come in handy. Example: # # <%= text_field "person", "name", "index" => 1 %> # # becomes # # # # There's also methods for helping to build form tags in link:classes/ActionView/Helpers/FormOptionsHelper.html, # link:classes/ActionView/Helpers/DateHelper.html, and link:classes/ActionView/Helpers/ActiveRecordHelper.html module FormHelper # Creates a form and a scope around a specific model object, which is then used as a base for questioning about # values for the fields. Examples: # # <% form_for :person, @person, :url => { :action => "update" } do |f| %> # First name: <%= f.text_field :first_name %> # Last name : <%= f.text_field :last_name %> # Biography : <%= f.text_area :biography %> # Admin? : <%= f.check_box :admin %> # <% end %> # # Worth noting is that the form_for tag is called in a ERb evaluation block, not a ERb output block. So that's <% %>, # not <%= %>. Also worth noting is that the form_for yields a form_builder object, in this example as f, which emulates # the API for the stand-alone FormHelper methods, but without the object name. So instead of text_field :person, :name, # you get away with f.text_field :name. # # That in itself is a modest increase in comfort. The big news is that form_for allows us to more easily escape the instance # variable convention, so while the stand-alone approach would require text_field :person, :name, :object => person # to work with local variables instead of instance ones, the form_for calls remain the same. You simply declare once with # :person, person and all subsequent field calls save :person and :object => person. # # Also note that form_for doesn't create an exclusive scope. It's still possible to use both the stand-alone FormHelper methods # and methods from FormTagHelper. Example: # # <% form_for :person, @person, :url => { :action => "update" } do |f| %> # First name: <%= f.text_field :first_name %> # Last name : <%= f.text_field :last_name %> # Biography : <%= text_area :person, :biography %> # Admin? : <%= check_box_tag "person[admin]", @person.company.admin? %> # <% end %> # # Note: This also works for the methods in FormOptionHelper and DateHelper that are designed to work with an object as base. # Like collection_select and datetime_select. # # You can also build forms using a customized FormBuilder class. Subclass FormBuilder and override or define some more helpers, # then use your custom builder like so: # # <% form_for :person, @person, :url => { :action => "update" }, :builder => LabellingFormBuilder do |f| %> # <%= f.text_field :first_name %> # <%= f.text_field :last_name %> # <%= text_area :person, :biography %> # <%= check_box_tag "person[admin]", @person.company.admin? %> # <% end %> # # In many cases you will want to wrap the above in another helper, such as: # # def labelled_form_for(name, object, options, &proc) # form_for(name, object, options.merge(:builder => LabellingFormBuiler), &proc) # end # def form_for(object_name, object, options = {}, &proc) raise ArgumentError, "form_for requires a block!" unless proc url_options = options.delete(:url) || {} form_tag_selector = options.delete(:form_tag_selector) || :form_tag form_options = options.delete(:html) || {} [:method, :multipart].each { |key| form_options[key] = options.delete(key) if options.key? key } fields_for(object_name, object, options.merge(:proc => proc)) do |builder| if form_tag_selector == :form_remote_tag concat send(form_tag_selector, form_options.merge(:url => url_options, :html => form_options)), proc.binding else concat send(form_tag_selector, url_options, form_options), proc.binding end builder.build_form(url_options, form_options) { proc.call builder } concat end_form_tag, proc.binding end end # Creates a scope around a specific model object like form_for, but doesn't create the form tags themselves. This makes # fields_for suitable for specifying additional model objects in the same form. Example: # # <% form_for :person, @person, :url => { :action => "update" } do |person_form| %> # First name: <%= person_form.text_field :first_name %> # Last name : <%= person_form.text_field :last_name %> # # <% fields_for :permission, @person.permission do |permission_fields| %> # Admin? : <%= permission_fields.check_box :admin %> # <% end %> # <% end %> # # Note: This also works for the methods in FormOptionHelper and DateHelper that are designed to work with an object as base. # Like collection_select and datetime_select. def fields_for(object_name, object, options = {}, &proc) raise ArgumentError, "fields_for requires a block!" unless proc builder = options[:builder] || FormBuilder form_builder = builder.new(object_name, object, self, options, options[:proc] || proc) proc.call(form_builder) end # Returns an input tag of the "text" type tailored for accessing a specified attribute (identified by +method+) on an object # assigned to the template (identified by +object+). Additional options on the input tag can be passed as a # hash with +options+. # # Examples (call, result): # text_field("post", "title", "size" => 20) # def text_field(object_name, method, options = {}) InstanceTag.new(object_name, method, self, nil, options.delete(:object)).to_input_field_tag("text", options) end # Works just like text_field, but returns an input tag of the "password" type instead. def password_field(object_name, method, options = {}) InstanceTag.new(object_name, method, self, nil, options.delete(:object)).to_input_field_tag("password", options) end # Works just like text_field, but returns an input tag of the "hidden" type instead. def hidden_field(object_name, method, options = {}) InstanceTag.new(object_name, method, self, nil, options.delete(:object)).to_input_field_tag("hidden", options) end # Works just like text_field, but returns an input tag of the "file" type instead, which won't have a default value. def file_field(object_name, method, options = {}) InstanceTag.new(object_name, method, self, nil, options.delete(:object)).to_input_field_tag("file", options) end # Returns a textarea opening and closing tag set tailored for accessing a specified attribute (identified by +method+) # on an object assigned to the template (identified by +object+). Additional options on the input tag can be passed as a # hash with +options+. # # Example (call, result): # text_area("post", "body", "cols" => 20, "rows" => 40) # def text_area(object_name, method, options = {}) InstanceTag.new(object_name, method, self, nil, options.delete(:object)).to_text_area_tag(options) end # Returns a checkbox tag tailored for accessing a specified attribute (identified by +method+) on an object # assigned to the template (identified by +object+). It's intended that +method+ returns an integer and if that # integer is above zero, then the checkbox is checked. Additional options on the input tag can be passed as a # hash with +options+. The +checked_value+ defaults to 1 while the default +unchecked_value+ # is set to 0 which is convenient for boolean values. Usually unchecked checkboxes don't post anything. # We work around this problem by adding a hidden value with the same name as the checkbox. # # Example (call, result). Imagine that @post.validated? returns 1: # check_box("post", "validated") # # # # Example (call, result). Imagine that @puppy.gooddog returns no: # check_box("puppy", "gooddog", {}, "yes", "no") # # def check_box(object_name, method, options = {}, checked_value = "1", unchecked_value = "0") InstanceTag.new(object_name, method, self, nil, options.delete(:object)).to_check_box_tag(options, checked_value, unchecked_value) end # Returns a radio button tag for accessing a specified attribute (identified by +method+) on an object # assigned to the template (identified by +object+). If the current value of +method+ is +tag_value+ the # radio button will be checked. Additional options on the input tag can be passed as a # hash with +options+. # Example (call, result). Imagine that @post.category returns "rails": # radio_button("post", "category", "rails") # radio_button("post", "category", "java") # # # def radio_button(object_name, method, tag_value, options = {}) InstanceTag.new(object_name, method, self, nil, options.delete(:object)).to_radio_button_tag(tag_value, options) end end class InstanceTag #:nodoc: include Helpers::TagHelper attr_reader :method_name, :object_name DEFAULT_FIELD_OPTIONS = { "size" => 30 }.freeze unless const_defined?(:DEFAULT_FIELD_OPTIONS) DEFAULT_RADIO_OPTIONS = { }.freeze unless const_defined?(:DEFAULT_RADIO_OPTIONS) DEFAULT_TEXT_AREA_OPTIONS = { "cols" => 40, "rows" => 20 }.freeze unless const_defined?(:DEFAULT_TEXT_AREA_OPTIONS) DEFAULT_DATE_OPTIONS = { :discard_type => true }.freeze unless const_defined?(:DEFAULT_DATE_OPTIONS) def initialize(object_name, method_name, template_object, local_binding = nil, object = nil) @object_name, @method_name = object_name.to_s, method_name.to_s @template_object, @local_binding = template_object, local_binding @object = object if @object_name.sub!(/\[\]$/,"") @auto_index = @template_object.instance_variable_get("@#{Regexp.last_match.pre_match}").id_before_type_cast end end def to_input_field_tag(field_type, options = {}) options = options.stringify_keys options["size"] ||= options["maxlength"] || DEFAULT_FIELD_OPTIONS["size"] options = DEFAULT_FIELD_OPTIONS.merge(options) if field_type == "hidden" options.delete("size") end options["type"] = field_type options["value"] ||= value_before_type_cast unless field_type == "file" add_default_name_and_id(options) tag("input", options) end def to_radio_button_tag(tag_value, options = {}) options = DEFAULT_RADIO_OPTIONS.merge(options.stringify_keys) options["type"] = "radio" options["value"] = tag_value options["checked"] = "checked" if value.to_s == tag_value.to_s pretty_tag_value = tag_value.to_s.gsub(/\s/, "_").gsub(/\W/, "").downcase options["id"] = @auto_index ? "#{@object_name}_#{@auto_index}_#{@method_name}_#{pretty_tag_value}" : "#{@object_name}_#{@method_name}_#{pretty_tag_value}" add_default_name_and_id(options) tag("input", options) end def to_text_area_tag(options = {}) options = DEFAULT_TEXT_AREA_OPTIONS.merge(options.stringify_keys) add_default_name_and_id(options) content_tag("textarea", html_escape(options.delete('value') || value_before_type_cast), options) end def to_check_box_tag(options = {}, checked_value = "1", unchecked_value = "0") options = options.stringify_keys options["type"] = "checkbox" options["value"] = checked_value checked = case value when TrueClass, FalseClass value when NilClass false when Integer value != 0 when String value == checked_value else value.to_i != 0 end if checked || options["checked"] == "checked" options["checked"] = "checked" else options.delete("checked") end add_default_name_and_id(options) tag("input", options) << tag("input", "name" => options["name"], "type" => "hidden", "value" => unchecked_value) end def to_date_tag() defaults = DEFAULT_DATE_OPTIONS.dup date = value || Date.today options = Proc.new { |position| defaults.merge(:prefix => "#{@object_name}[#{@method_name}(#{position}i)]") } html_day_select(date, options.call(3)) + html_month_select(date, options.call(2)) + html_year_select(date, options.call(1)) end def to_boolean_select_tag(options = {}) options = options.stringify_keys add_default_name_and_id(options) tag_text = "" end def to_content_tag(tag_name, options = {}) content_tag(tag_name, value, options) end def object @object || @template_object.instance_variable_get("@#{@object_name}") end def value unless object.nil? object.send(@method_name) end end def value_before_type_cast unless object.nil? object.respond_to?(@method_name + "_before_type_cast") ? object.send(@method_name + "_before_type_cast") : object.send(@method_name) end end private def add_default_name_and_id(options) if options.has_key?("index") options["name"] ||= tag_name_with_index(options["index"]) options["id"] ||= tag_id_with_index(options["index"]) options.delete("index") elsif @auto_index options["name"] ||= tag_name_with_index(@auto_index) options["id"] ||= tag_id_with_index(@auto_index) else options["name"] ||= tag_name options["id"] ||= tag_id end end def tag_name "#{@object_name}[#{@method_name}]" end def tag_name_with_index(index) "#{@object_name}[#{index}][#{@method_name}]" end def tag_id "#{@object_name}_#{@method_name}" end def tag_id_with_index(index) "#{@object_name}_#{index}_#{@method_name}" end end class FormBuilder # The methods which wrap a form helper call. class_inheritable_accessor :field_helpers self.field_helpers = (FormHelper.instance_methods - ['form_for']) def initialize(object_name, object, template, options, proc) @object_name, @object, @template, @options, @proc = object_name, object, template, options, proc end # An empty stub that can be overriden to wrap a form created by form_for. def build_form(url_options, form_options, &proc) proc.call self end (field_helpers - %w(check_box radio_button)).each do |selector| src = <<-end_src def #{selector}(method, options = {}) @template.send(#{selector.inspect}, @object_name, method, options.merge(:object => @object)) end end_src class_eval src, __FILE__, __LINE__ end def check_box(method, options = {}, checked_value = "1", unchecked_value = "0") @template.check_box(@object_name, method, options.merge(:object => @object), checked_value, unchecked_value) end def radio_button(method, tag_value, options = {}) @template.radio_button(@object_name, method, tag_value, options.merge(:object => @object)) end end end end