Passing proc blocks to rhtml templates

Rails
1

I want to create layout components that function like my layout does.
A
layout can yield the body content, is there any way to get this
functionality in rhtml templates? For example, say I have a layout
component that has a title bar and a content area. If it is a box with
rounded corners I do not want to repeat this html everywhere, so I’ll
make a
helper. Here is what I have to do now:

<%= start_mini_window(“Log in!”) %>
log in form html here
<%= end_mini_window %>

Is it possible to do this?

<% mini_window(“Log in!”) do %>
log in form html here
<% end %>

This feels cleaner to me, but I was unable to get it working. I stopped
trying to get this working when I realized that render() only uses your
proc
block when creating a javascriptgenerator.

Any ideas?

Thanks,
Zack H.

2

On 11/29/06, Zack H. [email protected] wrote:

<%= end_mini_window %>

Any ideas?

Thanks,
Zack H.

I’m not sure that I can help you with your particular case, but the
form_for
helper works like this.

The code for that method is

  def form_for(object_name, *args, &proc)
    raise ArgumentError, "Missing block" unless block_given?
    options = args.last.is_a?(Hash) ? args.pop : {}
    concat(form_tag(options.delete(:url) || {},

options.delete(:html) || {}), proc.binding)
fields_for(object_name, *(args << options), &proc)
concat(‘’, proc.binding)
end

This can be found at
http://dev.rubyonrails.org/svn/rails/trunk/actionpack/lib/action_view/helpers/form_helper.rb

That might give you some ideas.

3

I looked at form_for because it is a good example of the benefits to
proc
blocks in templates. The code didn’t tell me a whole lot unfortunately.
What I really want to do is take the proc block contents and yield it
into a
string, then pass that string to a partial template. I didn’t see
form_for
doing that, but maybe I missed something.

If I can yield the proc block contents into a string, that lets me
actually
pass parameters to the block and derive benefits like form_for does.
Can
anyone explain how/if this is possible, and how it would work with
concat()?

Thanks!
Zack

4

I think this article at “Err the Blog” has the solution you are looking
for:

5

Perfect. Thanks

Zack

6

copy paste from form_for() method. you may have to figure out how to
pass actual params.
concat() just append strings to output buffer string.

in your controller helper:

def widget(&proc)
raise ArgumentError, “Missing block” unless block_given?
concat(‘

hello world

’, proc.binding)
yield proc
concat(‘
’, proc.binding)
end

in rhtml

<% widget do |w| %>
does it work?
<% end %>

and you got

hello world

does it work?

wuyaSea operator
http://www.wuyaSea.com