Ajax

Rails
1

Hi guys,

I’ve got a little problem relating to Ajax and Rails, namely updating
multiple divs!

I have created a message inbox for a system I’ve developed, and when a
user clicks on a message, I want the number of read messages to decrease
by one (this is displayed in 2 divs in separate locations on the page),
and I don’t think the :update => ‘mydiv’ in ‘link_to_remote’ can cope
with more than one div,

I have looked at the example in the pick-axe (Chapter 18, page 403-404)
but it doesn’t seem to make much sense!

Any help is appreciated!

Cheers, Mick

2

If you want to update more than one div, rjs is the best way to go.

For example

def some_method
//some stuff
render :update do |page|
page.replace_html ‘div1’, :partial => ‘partial1’
page.replace_html 'div2, :partial => ‘partial2’
end
end

Or you can put these calls in a rjs file (which has precedence over
a .rhtml file).

Greetz,

Joram

3

If you have access to Agile with Rails v. 2, it has a good tutorial on
what’s called RJS templates. Basically, you use Ruby to write out
javascript
that gets executed on the client (the {executeScripts: true} of
Prototype).

Some info is also available on the api page:
http://api.rubyonrails.org/classes/ActionView/Helpers/PrototypeHelper/JavaScriptGenerator/GeneratorMethods.html#M000559

You can write RJS in your controller or as a partial

_partial_name.rjs

Note: if you do this, you must not use :update, or the resulting
javascript
will be printed to the page.

Jason

4

Hi Mick,

Mick wrote:

I’ve got a little problem relating to Ajax and Rails,
namely updating multiple divs!

Joram is correct. You want to use RJS. And you are correct. The
:update
will not update more than one element.

I highly recommend Cody F.'s RJS Tutorial on O’Reilly. It’s a $10
PDF
that’s well worth the money and will have you productive and feeling
comfortable in a couple of hours.

Best regards,
Bill

5

Thanks everyone, you’ve all been more than helpful,

cheers

Mick