Module: ActionView::Helpers::RenderingHelper
Relationships & Source Files | |
Extension / Inclusion / Inheritance Descendants | |
Included In:
ActionDispatch::DebugView,
::ActionView::Base ,
::ActionView::Helpers ,
::ActionView::TestCase ,
::ActionView::TestCase::Behavior
| |
Defined in: | actionview/lib/action_view/helpers/rendering_helper.rb |
Overview
Action View Rendering Helpers
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)
Overrides _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)
Overrides _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 97
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:locals
to pass in those. -
:inline
- Renders an inline template similar to how it’s done in the controller. -
: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/plain
from ActionDispatch::Response object.
If no options
hash is passed or if :update
is specified, then:
If an object responding to render_in
is passed, render_in
is called on the object, passing in the current view context.
Otherwise, a partial is rendered using the second parameter as the locals hash.
# File 'actionview/lib/action_view/helpers/rendering_helper.rb', line 30
def render( = {}, locals = {}, &block) case when Hash in_rendering_context( ) do |renderer| if block_given? view_renderer.render_partial(self, .merge(partial: [:layout]), &block) else view_renderer.render(self, ) end end else if .respond_to?(:render_in) .render_in(self, &block) else view_renderer.render_partial(self, partial: , locals: locals, &block) end end end