Module: ActionView::Helpers::RenderingHelper
| Relationships & Source Files | |
| Extension / Inclusion / Inheritance Descendants | |
| Included In: | |
| Defined in: | actionview/lib/action_view/helpers/rendering_helper.rb | 
Overview
Action View Rendering
Implements methods that allow rendering from a view context. In order to use this module, all you need is to implement view_renderer that returns an ::ActionView::Renderer object.
Instance Method Summary
- 
    
      #_layout_for(*args, &block)  
    
    Overwrites _layout_for in the context object so it supports the case a block is passed to a partial. 
- 
    
      #render(options = {}, locals = {}, &block)  
    
    Returns the result of a render that's dictated by the options hash. 
Instance Method Details
#_layout_for(*args, &block)
Overwrites _layout_for in the context object so it supports the case a block is passed to a partial. Returns the contents that are yielded to a layout, given a name or a block.
You can think of a layout as a method that is called with a block. If the user calls yield :some_name, the block, by default, returns content_for(:some_name). If the user calls simply yield, the default block returns content_for(:layout).
The user can override this default by passing a block to the layout:
# The template
<%= render layout: "my_layout" do %>
  Content
<% end %>
# The layout
<html>
  <%= yield %>
</html>In this case, instead of the default block, which would return content_for(:layout), this method returns the block that was passed in to render :layout, and the response would be
<html>
  Content
</html>
Finally, the block can take block arguments, which can be passed in by yield:
# The template
<%= render layout: "my_layout" do |customer| %>
  Hello <%= customer.name %>
<% end %>
# The layout
<html>
  <%= yield Struct.new(:name).new("David") %>
</html>In this case, the layout would receive the block passed into render :layout, and the struct specified would be passed into the block as an argument. The result would be
<html>
  Hello David
</html>
# File 'actionview/lib/action_view/helpers/rendering_helper.rb', line 87
def _layout_for(*args, &block) name = args.first if block && !name.is_a?(Symbol) capture(*args, &block) else super end end
#render(options = {}, locals = {}, &block)
Returns the result of a render that's dictated by the options hash. The primary options are:
- 
:partial- See ::ActionView::PartialRenderer.
- 
:file- Renders an explicit template file (this used to be the old default), add:localsto pass in those.
- 
:inline- Renders an inline template similar to how it's done in the controller.
- 
:text- Renders the text passed in out.
- 
:plain- Renders the text passed in out. Setting the content type astext/plain.
- 
:html- Renders the HTML safe string passed in out, otherwise performs HTML escape on the string first. Setting the content type astext/html.
- 
:body- Renders the text passed in, and inherits the content type oftext/htmlfrom ::ActionDispatch::Response object.
If no options hash is passed or :update specified, the default is to render a partial and use the second parameter as the locals hash.
# File 'actionview/lib/action_view/helpers/rendering_helper.rb', line 26
def render( = {}, locals = {}, &block) case when Hash if block_given? view_renderer.render_partial(self, .merge(:partial => [:layout]), &block) else view_renderer.render(self, ) end else view_renderer.render_partial(self, :partial => , :locals => locals) end end