From eb9af20b7cc0e374277cf330bdd404f9daab28ec Mon Sep 17 00:00:00 2001 From: Yehuda Katz Date: Thu, 22 Jan 2009 16:18:10 -0600 Subject: Begin unifying the interface between ActionController and ActionView --- actionpack/lib/action_view/render/partials.rb | 300 ++++++++++++++++++++++++++ 1 file changed, 300 insertions(+) create mode 100644 actionpack/lib/action_view/render/partials.rb (limited to 'actionpack/lib/action_view/render/partials.rb') diff --git a/actionpack/lib/action_view/render/partials.rb b/actionpack/lib/action_view/render/partials.rb new file mode 100644 index 0000000000..aa4c4af213 --- /dev/null +++ b/actionpack/lib/action_view/render/partials.rb @@ -0,0 +1,300 @@ +module ActionView + # There's also a convenience method for rendering sub templates within the current controller that depends on a + # single object (we call this kind of sub templates for partials). It relies on the fact that partials should + # follow the naming convention of being prefixed with an underscore -- as to separate them from regular + # templates that could be rendered on their own. + # + # In a template for Advertiser#account: + # + # <%= render :partial => "account" %> + # + # This would render "advertiser/_account.erb" and pass the instance variable @account in as a local variable + # +account+ to the template for display. + # + # In another template for Advertiser#buy, we could have: + # + # <%= render :partial => "account", :locals => { :account => @buyer } %> + # + # <% for ad in @advertisements %> + # <%= render :partial => "ad", :locals => { :ad => ad } %> + # <% end %> + # + # This would first render "advertiser/_account.erb" with @buyer passed in as the local variable +account+, then + # render "advertiser/_ad.erb" and pass the local variable +ad+ to the template for display. + # + # == Rendering a collection of partials + # + # The example of partial use describes a familiar pattern where a template needs to iterate over an array and + # render a sub template for each of the elements. This pattern has been implemented as a single method that + # accepts an array and renders a partial by the same name as the elements contained within. So the three-lined + # example in "Using partials" can be rewritten with a single line: + # + # <%= render :partial => "ad", :collection => @advertisements %> + # + # This will render "advertiser/_ad.erb" and pass the local variable +ad+ to the template for display. An + # iteration counter will automatically be made available to the template with a name of the form + # +partial_name_counter+. In the case of the example above, the template would be fed +ad_counter+. + # + # NOTE: Due to backwards compatibility concerns, the collection can't be one of hashes. Normally you'd also + # just keep domain objects, like Active Records, in there. + # + # == Rendering shared partials + # + # Two controllers can share a set of partials and render them like this: + # + # <%= render :partial => "advertisement/ad", :locals => { :ad => @advertisement } %> + # + # This will render the partial "advertisement/_ad.erb" regardless of which controller this is being called from. + # + # == Rendering objects with the RecordIdentifier + # + # Instead of explicitly naming the location of a partial, you can also let the RecordIdentifier do the work if + # you're following its conventions for RecordIdentifier#partial_path. Examples: + # + # # @account is an Account instance, so it uses the RecordIdentifier to replace + # # <%= render :partial => "accounts/account", :locals => { :account => @buyer } %> + # <%= render :partial => @account %> + # + # # @posts is an array of Post instances, so it uses the RecordIdentifier to replace + # # <%= render :partial => "posts/post", :collection => @posts %> + # <%= render :partial => @posts %> + # + # == Rendering the default case + # + # If you're not going to be using any of the options like collections or layouts, you can also use the short-hand + # defaults of render to render partials. Examples: + # + # # Instead of <%= render :partial => "account" %> + # <%= render "account" %> + # + # # Instead of <%= render :partial => "account", :locals => { :account => @buyer } %> + # <%= render "account", :account => @buyer %> + # + # # @account is an Account instance, so it uses the RecordIdentifier to replace + # # <%= render :partial => "accounts/account", :locals => { :account => @account } %> + # <%= render(@account) %> + # + # # @posts is an array of Post instances, so it uses the RecordIdentifier to replace + # # <%= render :partial => "posts/post", :collection => @posts %> + # <%= render(@posts) %> + # + # == Rendering partials with layouts + # + # Partials can have their own layouts applied to them. These layouts are different than the ones that are + # specified globally for the entire action, but they work in a similar fashion. Imagine a list with two types + # of users: + # + # <%# app/views/users/index.html.erb &> + # Here's the administrator: + # <%= render :partial => "user", :layout => "administrator", :locals => { :user => administrator } %> + # + # Here's the editor: + # <%= render :partial => "user", :layout => "editor", :locals => { :user => editor } %> + # + # <%# app/views/users/_user.html.erb &> + # Name: <%= user.name %> + # + # <%# app/views/users/_administrator.html.erb &> + #
+ # Budget: $<%= user.budget %> + # <%= yield %> + #
+ # + # <%# app/views/users/_editor.html.erb &> + #
+ # Deadline: <%= user.deadline %> + # <%= yield %> + #
+ # + # ...this will return: + # + # Here's the administrator: + #
+ # Budget: $<%= user.budget %> + # Name: <%= user.name %> + #
+ # + # Here's the editor: + #
+ # Deadline: <%= user.deadline %> + # Name: <%= user.name %> + #
+ # + # You can also apply a layout to a block within any template: + # + # <%# app/views/users/_chief.html.erb &> + # <% render(:layout => "administrator", :locals => { :user => chief }) do %> + # Title: <%= chief.title %> + # <% end %> + # + # ...this will return: + # + #
+ # Budget: $<%= user.budget %> + # Title: <%= chief.name %> + #
+ # + # As you can see, the :locals hash is shared between both the partial and its layout. + # + # If you pass arguments to "yield" then this will be passed to the block. One way to use this is to pass + # an array to layout and treat it as an enumerable. + # + # <%# app/views/users/_user.html.erb &> + #
+ # Budget: $<%= user.budget %> + # <%= yield user %> + #
+ # + # <%# app/views/users/index.html.erb &> + # <% render :layout => @users do |user| %> + # Title: <%= user.title %> + # <% end %> + # + # This will render the layout for each user and yield to the block, passing the user, each time. + # + # You can also yield multiple times in one layout and use block arguments to differentiate the sections. + # + # <%# app/views/users/_user.html.erb &> + #
+ # <%= yield user, :header %> + # Budget: $<%= user.budget %> + # <%= yield user, :footer %> + #
+ # + # <%# app/views/users/index.html.erb &> + # <% render :layout => @users do |user, section| %> + # <%- case section when :header -%> + # Title: <%= user.title %> + # <%- when :footer -%> + # Deadline: <%= user.deadline %> + # <%- end -%> + # <% end %> + module Partials + extend ActiveSupport::Memoizable + + def _render_partial(options = {}) #:nodoc: + options[:locals] ||= {} + + case path = partial = options[:partial] + when *_array_like_objects + return _render_partial_collection(partial, options) + else + if partial.is_a?(ActionView::Helpers::FormBuilder) + path = partial.class.to_s.demodulize.underscore.sub(/_builder$/, '') + options[:locals].merge!(path.to_sym => partial) + elsif !partial.is_a?(String) + options[:object] = object = partial + path = ActionController::RecordIdentifier.partial_path(object, controller_path) + end + _, _, prefix, object = parts = partial_parts(path, options) + template = find_by_parts(*parts) + _render_partial_object(template, options, (object unless object == true)) + end + end + + private + def partial_parts(name, options) + segments = name.split("/") + parts = segments.pop.split(".") + + case parts.size + when 1 + parts + when 2, 3 + extension = parts.delete_at(1).to_sym + if formats.include?(extension) + self.formats.replace [extension] + end + parts.pop if parts.size == 2 + end + + path = parts.join(".") + prefix = segments[0..-1].join("/") + prefix = prefix.blank? ? controller_path : prefix + parts = [path, formats, prefix] + parts.push options[:object] || true + end + + def _render_partial_with_block(layout, block, options) + @_proc_for_layout = block + concat(_render_partial(options.merge(:partial => layout))) + ensure + @_proc_for_layout = nil + end + + def _render_partial_with_layout(layout, options) + if layout + prefix = controller && !layout.include?("/") ? controller.controller_path : nil + layout = find_by_parts(layout, formats, prefix, true) + end + content = _render_partial(options) + return _render_content_with_layout(content, layout, options[:locals]) + end + + def _deprecated_ivar_assign(template) + if respond_to?(:controller) + ivar = :"@#{template.variable_name}" + object = + if controller.instance_variable_defined?(ivar) + ActiveSupport::Deprecation::DeprecatedObjectProxy.new( + controller.instance_variable_get(ivar), + "#{ivar} will no longer be implicitly assigned to #{template.variable_name}") + end + end + end + + def _array_like_objects + array_like = [Array] + if defined?(ActiveRecord) + array_like.push(ActiveRecord::Associations::AssociationCollection, ActiveRecord::NamedScope::Scope) + end + array_like + end + + def _render_partial_object(template, options, object = nil) + if options.key?(:collection) + _render_partial_collection(options.delete(:collection), options, template) + else + locals = (options[:locals] ||= {}) + object ||= locals[:object] || locals[template.variable_name] + + _set_locals(object, locals, template, options) + _render_template(template, locals) + end + end + + def _set_locals(object, locals, template, options) + object ||= _deprecated_ivar_assign(template) + locals[:object] = locals[template.variable_name] = object + locals[options[:as]] = object if options[:as] + end + + def _render_partial_collection(collection, options = {}, passed_template = nil) #:nodoc: + return nil if collection.blank? + + spacer = options[:spacer_template] ? _render_partial(:partial => options[:spacer_template]) : '' + + locals = (options[:locals] ||= {}) + index, @_partial_path = 0, nil + collection.map do |object| + template = passed_template || begin + _partial_path = + ActionController::RecordIdentifier.partial_path(object, controller_path) + template = _pick_partial_template(_partial_path) + end + + _set_locals(object, locals, template, options) + locals[template.counter_name] = index + + index += 1 + _render_template(template, locals) + end.join(spacer) + end + + def _pick_partial_template(partial_path) #:nodoc: + prefix = controller_path unless partial_path.include?('/') + find_by_parts(partial_path, formats, prefix, true) + end + memoize :_pick_partial_template + end +end -- cgit v1.2.3