How do you pass html objects from the view to the helper cla

Rails
1

I would like to pass the title to the helper class and manipulate it.

I have in the view

test

In the helper, I have

def hide_and_reset(div)
update_page do |page|
if page[div].title == ‘show’
page[div].hide
page[div].title = ‘hide’
else
page[div].title = ‘show’
page[div].show
end
end
end

2

[email protected] wrote:

def hide_and_reset(div)
update_page do |page|
if page[div].title == ‘show’
page[div].hide
page[div].title = ‘hide’
else
page[div].title = ‘show’
page[div].show
end
end
end

You can’t. The helper has already been run on the server side before the
page is sent to the client. At that point the browser has no idea that
there was a helper function in the original .rhtml file.

To hide or show DIVs on the browser you need to write some JavaScript or
if the hide/show conditions depend on information on the server you can
use Ajax.

–
Michael W.

3

Thanks. I can call the helper with this line in my code in the view.

<%= link_to_function image_tag(“graphics/
select04.gif”, :alt=>‘Programming’, :size=>‘100x20’, :border=>0),
hide_and_reset(:select02_div, :select01_div) %>

The helper class seems to update the view. I can hide …, but I don’t know how to show
it or know how to check to see if it is hidden using the helper class.

4

[email protected] wrote:

Thanks. I can call the helper with this line in my code in the view.

<%= link_to_function image_tag(“graphics/
select04.gif”, :alt=>‘Programming’, :size=>‘100x20’, :border=>0),
hide_and_reset(:select02_div, :select01_div) %>

The helper class seems to update the view. I can hide …, but I don’t know how to show
it or know how to check to see if it is hidden using the helper class.

The hide_and_reset() in the link_to_function looks like a JavaScript
function, not a Rails helper method.

–
Michael W.

5

In this case, your helper function is actually returning a chunk of
javascript that is called when you click on the image. Ruby’s not
changing the page – javascript is. update_page is generating this
javascript based on the block you gave it. Unfortunately, in this
case, the javascript you’re getting is not what you expect. If you
add <%= hide_and_reset(:select02_div, :select01_div) %> you can see
what’s being created on your behalf.

update_page() is good in a lot of simple cases, but if you really need
flexibility, you’ll have to dip down into native javascript.

For this case something like the following will work

def hide_and_reset(div)
update_page do |page|
el = page[div]
page << <-“end”
if (#{el}.title == “show”) { #{el}.hide(); #{el}.title =
“hide”; }
else { #{el}.show(); #{el}.title = “show”; }
end
end
end

On Mar 9, 12:55 pm, “[email protected]” [email protected]

6

Thanks guys. I see your point in not wasting server calls just for
simple stuff that should be done on the client only in plain
javascript. I use the Oreilly book Ruby on Rails Up and Running. It’s
too basic. I was wondering if you guys have any good books or
tutorials you recommend that provides more advance use of ruby on
rails, especially with AJAX.

7

For most things you don’t actually need ajax – instead you can
usually get away with plain javascript. The ORA javascript and dhtml
books are good starts:

On Mar 9, 1:45 pm, “[email protected]” [email protected]