RJS template dont-know-how

rubyonrails-talk
1

Hello!

Get a problem out here. I need to update flash notice with every one remote request. Flash.now[:notice] does that trick but not for remoting methods. So I've applied some after_filter (say clear_notice_on_xhr) but its render method not evaluating or i can't see the result:   def clear_notice_on_xhr     return unless request.xhr?     render :update do |page|       page.replace_html("notice" , :partial => "layouts/notice")     end     rescue       nil   end

Help!

2

If I were you I'd remove that rescue nil statement as that will swallow any errors that might be telling you what is wrong.

Fred

3

ActionController::DoubleRenderError (Can only render or redirect once per action) raises. So, thats the problem - I cant "inject" RJS into template.

4

Anyone?

5

Anyone?

You;ve already found the problem: you've already rendered, so you
can't render again. If people could see the whole story rather than
just one bit, someone might be able to suggest an alternative.

Fred.

6

I found the problem but i dont know how to solve it. Story: I want to evaluate the same page.replace_html method in every rjs template. Question: How to do that?

7

I think it does not work to implement it as 'after_filter' as long the action executed before that filter calls 'render', too.

so for example:

def index     ...    # calls (implecitely) render index.erb.html # or in your case another rjs end

def clear_notice_on_xhr     return unless request.xhr?     # CALLS RENDER AGAIN ON THE SAME HTTP REQUEST     # that doesnt work 'cause IMHO rails does not know how to merge these 2 render outputs     render :update do |page|       page.replace_html("notice" , :partial => "layouts/notice")     end     rescue       nil   end

mercy blog.odeley.com

8

Ok. I know from the beginning that DoubleRenderError, but how to include that same page.replace_html method in every rjs template? Rails seemed to be dynamic and powerful but in fact i cant implement that very simple scenario... silly.

9

sinm wrote:

Ok. I know from the beginning that DoubleRenderError, but how to include that same page.replace_html method in every rjs template? Rails seemed to be dynamic and powerful but in fact i cant implement that very simple scenario... silly.

Rather than use a partial, create the text in your after_filter method and add a call to the end of the response body to action it as javascript. This is a little messy, but you could hide it away. There may well be an easier way, but this seems to work for me:

after_filter :clear_notice_on_xhr

def clear_notice_on_xhr   new_text = "New flash notice created here"   script = <<EOS <script type="text/javascript"> //<![CDATA[ $('notice').update('#{new_text}') //]]> </script> EOS   response.body << script end

This assumes you are including the Prototype javascript library in your pages (will need re-writing otherwise) and the tag where you display your flash has an id of "notice".

10

Thanx Mark for your try! Really messy but it really works. Finally i ended up with slightly different version.

  after_filter :clear_notice_on_xhr

  #TODO: bad smell   def clear_notice_on_xhr     return unless request.xhr?     response.body = "$('notice').update('');" + response.body     rescue       nil #optional   end