This code is working fine:
<%= render 'sidebars/pages', :object => @categories = pages , :object => { @myobject => '1', @mmyobject => '2' } %>
If I change to this:
<%= render 'sidebars/pages', :object => { @categories => pages, @myobject => '1', @mmyobject => '2' } %>
Then I receive a error from the partial when it try to iterate @categories:
undefined method `each' for nil:NilClass
I'm very new to ruby and rails also, I appreciate any help.
Cheers!
When you pass an :object to a Rails partial, a local variable (not an instance variable, beginning with @) is defined within the partial which has the same name as the partial. So for the partial sidebars/_pages.html.erb, your local variable will be called pages.
The value of the pages local variable is the Hash you passed as the value of the :object option, and none of the instance variables you had in your "outer" view will be available (such as @categories or @myobject). So you'll need to access those via the pages local variable.
You're probably looking for something like this:
<%= render 'sidebars/pages', :object => { :categories => @categories, :myobject => '1', :mmyobject => '2' } %>
And in sidebars/_pages.html.erb, you might have something like this:
<p><%= pages[:myobject] %></p>
<ul>
<% pages[:categories].each do |category| %>
<li><%= category %></li>
<% end %>
</ul>
See the Rails Guide to Layouts and Rendering's Partials section for more details.
Update:
An even better solution would be to use the :locals option, which accepts a Hash whose keys become local variables with the partial. For instance:
<%= render 'sidebars/pages', :locals => { :categories => @categories, :myobject => '1', :mmyobject => '2' } %>
And in sidebars/_pages.html.erb, you might have something like this:
<p><%= myobject %></p>
<p><%= mmyobject %></p>
<ul>
<% categories.each do |category| %>
<li><%= category %></li>
<% end %>
</ul>
@categories => pages. You probably don't want to have the Hash key be @categories, since you won't be accessing it via that key. It should probably be something like :categories => pages.@myobject and @mmyobject are not being passed to the view, since it does not raise any errors I was led to believe it was fine. I apologize for missing this.This line of code as mentioned above:
<%= render 'sidebars/pages', :object => @categories = pages , :object => { @myobject => '1', @mmyobject => '2' } %
Actually does not raise any errors but also does not pass @myobject and @mmyobject to the view.
Below is the correct* approach for specifying multiple objects with the render method:
<%= render 'sidebars/pages', :object => [@categories = pages, @myobject = '2'] %>
Like this I can pass multiple objects to the view, without having to define :object more than once.
*at least for my knowledge scope
@categories = pages is doing: that is setting the instance variable @categories to pages. Doing that assignment in the render statement isn't syntactically invalid, but it doesn't really give you anything. For instance, it does not mean you can access @categories within the partial.:locals option instead of :object. You could say render 'sidebars/pages', :locals => {:categories => @categories, :myobject => '2'}, and then you would have access to local variables called categories and myobject within the partial. See the "Passing Local Variables" section of the Rails Guide.<%= render 'sidebars/pages' %> lives inside a view and so far I knew only to pass multiple locals or one object at once from a view to a partial. With my example above I have available @categories in the partial, I double-checked this time. The method pages comes from a helper for testing purposes and is the same as Category.all. I'm testing with Rails 4.@categories = pages because I dont want it to be in the controller, if I make it available in the ApplicationController using the before_filter, then it will be requested even when it is not in use.