I understand this is a bad idea, but from what I've seen in ApplicationControllers, using:
render :layout => "something" ...
Should render using a layout located at views/layouts/something.html.erb
However, when I am making this call from inside of a view, it errors out with:
Missing partial my_controller_name/something with ...
Searched in:
* "{path here}/app/views"
Which seems to me its looking for a partial, instead of a layout as I specified. Does anyone know what is going on with that?
A sufficient example small enough to reproduce it:
<%= render :layout => 'something' do %>
<div>Hello</div>
<% end %>
This is all under Rails vs 4.0.2
render works differently in controllers than it does in views. In controllers, it's primarily for rendering action templates, while in views, it's primarily for rendering partial templates. When you want to render a specific layout for an action, you have a few options, but all of them are in the controller.
If you want every action in a particular controller to use that layout, you can either specify layout 'something' in that controller (usually near the top) or for a ApplesController, you can create a new layout in app/views/layouts/apples.html.erb and this will automatically be used as the default layout for the ApplesController.
If you want just a single action in a controller to use that layout, you can use your render layout: 'something' inside of a controller action, where the action to render is implied to be the current action.
Links from the Rails docs:
Action Rendering
Partial Rendering
Nested Layouts
Related
Within views/layouts/application.html I have the line <%= yield %>. This line is ultimately replaced by views directly corresponding to controller actions without any problems.
In one of my controllers, I am trying to render a partial instead of the default behaviour:
def show
#service_groups = ServiceGroup.where(deleted_at: nil)
render partial: 'table', locals: {rows: #service_groups, headers: service_group_headers}
end
I'm using a partial in this way so that I can use the same basic table structure for various different database tables (across different controllers).
This render partial code doesn't seem to work with the <%= yield %> line in the application layout. The partial code is just rendered on its own without the surrounding layout.
Why is this?
How do I rectify the problem?
Please let me know if I should be handling this a different way.
Thanks.
(migrating from comments)
What if you created a show.html.erb for that controller and placed render :partial there? It should work.
Explanation: Partials are to be used from "big" views. So, they are not wrapped in the layout on purpose!
The Rails guide Layouts and Rendering in Rails gives examples of render being used in both the controller and the view.
The section Rendering by default ... mentions that rendering is called by default. The section Using render gives an example of render being called within a controller:
def update
#book = Book.find(params[:id])
if #book.update(book_params)
redirect_to(#book)
else
render "edit"
end
end
The section Using Partials gives an example of render being used within the view, for example to use partials.
<%= render "menu" %>
Neither the cases of render being used in controller, nor the case of render being used in the view, strike me as illogical. But what's confusing me is that I thought one of the major concepts of Rails is model view controller separation, which means giving separate responsibilities to the model, view, and controller.
Why is it normal for render to be called in both the controller and in the view?
I'd say that if used properly, when render is used in a view, it should be primarily as an organization/structural tool in order to make the code for the view more understandable and readable.
When used in a controller, it's defining the entry point into the view and is the primary association between the action in the controller and the view.
The difference is subtle.
Somewhat new to rails, longtime programmer. I've got a question about views, controllers and partials really - wondering if I have this setup well.
I've got a pages controller, and on the index page (really the pages index method) I've got a partial in layouts called featured (ie app/views/layouts/_featured.html.erb) -- I've also got a Featured class. I would like basically the index of the featured class to be drawn here. But of course it's not working. SO the question is:
In the page itself I've got the <%= render 'features/index' %> which I'm beginning to think is the wrong way to go..
Do I axe this partial method and just call <%= render 'features/index' %> and let everything progress natively or
What would be the proper way of routing the featured collection to the partial? Since the controller is actually Pages it seems like I'm fighting against the tide.
<%= render 'features/index' %>
Doing this is wrong given your description. This will try to render a partial from app/views/features/_index.html.erb which you haven't mentioned.
To render the partial at app/views/layouts/_featured.html.erb you would do (perhaps a bit more verbose that is necessary)
<%= render partial: "layouts/featured" %>
The best suggestion I can offer is to pass a collection to this partial
<%= render partial: "layouts/featured", locals: { features: #features } %>
Since it seems your intention is for this partial to appear as a piece of a layout I will assume you wish for this partial to appear on multiple pages. This means on multiple actions you will need to have assigned the set of Feature instances this #features instance variable. One way to do this is a before_action.
before_action :setup_features
# ...
private
def setup_features
#features = Feature.all
end
A good place to start learning more about filters is in the Rails Guide
The partial at "app/view/layouts/_featured.html.erb" can only be rendered with
render 'featured'
and not 'featured/index'
render 'featured/index' will render "app/views/layouts/featured/_index.html.erb
Since the pages controller is really rendering the main index page in it's def index, all I had to do was #features = Feature.all and the variable is available for the partial pulled into the index page.
I need to get used to how simple rails is coming from other languages / frameworks.
I have code like render #posts to render my posts collection in an index template which the PostsController renders.
Now I have an Admin::PostsController that also should render the collection but when my posts controller renders #posts it looks for the admin/posts/_post.html.erb partial. Do I now have to write the partial path explicity? Is this feature by design or a bug? It doesn't seem to make sense.
Yes, you need to supply the path explicitly. And yes, this is by design.
It actually makes sense because Rails is a MVC framework and if you create a controller under a different namespace one would expect separate views for that controller too. Think about convenience, if you wanted to quickly bootstrap an application with a few simple commands, an application where there's a public view of posts and an admin view where all of the admin goodies for editing are, you would EXPECT to have a different directory to store all that admin views.
render #posts is a shortcut for a longer method signature.
In case of PostsController, it is a short cut for render :partial => "post", :collection => #posts; the partial is _post.html.erb and it is expected to be in app/views/posts folder.
In case of Admin::PostsController, it is a short cut for render :partial => "admin#post/post", :collection => #posts; the partial is _post.html.erb, and it is expected to be in app/views/admin/posts folder.
If you want a different partial to be used, you should specify it explicitly.
See the Rendering Collections section of Rails Guides page on Layouts & Rendering for detailed explanation.
What I want to do is have 2 different controllers, client and test_client. The client controller is already built and I want to create a test_client controller that i can use to play around with the UI of the client and adjust it as needed. I am mainly trying to get around the validation i have built into the client and its dependence on an admin controller that loads the data.
so i want the test_client controller to load a sample data set and then render the client controller's index view so i can adjust the clients UI. That is all.
I tried this in the test_clients index method:
class TestClient
def index
render :template => 'client/index'
end
end
but i get an error because it cannot find the client partials as it is looking in the current controllers view for them...
So I have looked into this already and most people say that you should never make such a call but i think that this case is a reasonable usage...I just need to figure out how to get it to work.
You will need to adjust your view so that the path to the partial you need is in the form 'controller/partial'. In this case probably 'client/partial'. Then you can simply use render 'client/index' as before.
So say somewhere in your view you have this:
<%= render :partial => 'info' %>
You will want to change it to this:
<%= render :partial => 'client/info' %>
Convert your client controller views to partials, create empty views for all actions in test_client controller, render client partials for respective test_client views.
Example:
client view
index.html.erb to _index.html.erb
test_client view
index.html.erb
in this view, <%=render :partial => 'clients/index', :locals =>{ }%>
You could do this in a number of ways and everyone is different. One way you could do it, is by putting your finders into a presenter. Then turn some data in the index view into a partial or you can render the template with layout set to false.
Then in the client_test view you can render that index with the presenter associated with it.