Rails 3, passing local variable to partial [duplicate]

Answer 1

I've spent several hours on this; in a view, render :partial => ? , :locals => (....} it seems if you first call:

render :partial => ? without a locals hash

and THEN call render :partial => ? with a locals hash the locals hash IS NOT passed to the view.

If the first call includes a locals hash with the same variables set to '' then the second call with REAL values will work.

Answer 2

I actually just use this syntax in Rails 3:

render "a_partial", :a_local_variable => whatever, :another_variable => another

Answer 3

I believe the problem is the trailing , info call. It is looking in the info object for img_style. You don't need it.

I love using partials but recently have seen the beauty in helper methods too, especially in simple renderings like this one.

def info_image(info, class_name="original")
   image_tag(info.image.url, :class => class_name)
end

then just

<%= info_image(first) %>

or

<%= info_image(first, "anotherclass") %>

in the view. Much cleaner.

If ever it becomes more complex. You'll only have to change code in one place.

Answer 4

This should work:

<%= render :partial => "info", :locals => { :img_style => "original" } %>

With this partial:

# infos/_info.html.erb
<%= image_tag(info.image.url, :class => img_style),  info %>

However if you are calling the partial wrong then try this as the partial:

# infos/_info.html.erb
<%= image_tag(info.image.url(img_style)),  info %>

Answer 5

Your code (the one you have shown in the first line) should work. There is no error. I have even tested it myself and it works for me.

The usual reasons for such errors are:

• misspelled variable name
• calling the partial also from some other place, where you do not pass a :local.

The fact that your model does not have the attribute "img_style" is not important.

I can see that in your infos/index.html.erb you have two places where you call render :partial => 'info', :object => ... and you do not have :locals here. Just the line numbers do not match with the stacktrace you have posted earlier, so it's hard to say which call causes the problem.

I guess both calls to the render method need corrections.

In the first one, be specific, and call render :partial => "info" instead of render "info". This may be a bug in Rails, but for some strange reason, :locals seem to not be passed to the view in this case.

In the second call to render just add the :locals.