I've tried to make sense of layouts but got lost..Also googled & looked at other similar questions on SO but none of them helped.
Say I have MVC's (scaffold'ed) for A and B, creating their ..views/A/index.html.erb and ..views/B/show.html.erb among the rest.
A's index method sets a #a_collection.
Within B's show view I want to:
<p>..stuff for B..</p>
<%= render A's index %>
<p>..some more B-stuff</p>
How can I render A's index in that place in B's show?
You don't typically render a view inside of another view. You use partials to share code across views. For example:
# app/views/products/_product.html.erb
# this is the code you want to reuse
<p>Product Name: <%= product.name %></p>
# app/views/products/index.html.erb
<%= render #products %>
# app/views/stores/show.html.erb
<h1><%= #store.name %></h1>
<h2>Our Products</h2>
<%= render #store.products %>
<%= render #products %> is shorthand for <%= render partial: "product", collection: #products %>.
This is just the implicit rendering - in many cases you'll want to add more partials and render them explicitly. Like for example the _form.html.erb partial that you'll find in the scaffolds thats used to share a form between the create and edit views.
Think of partials like the view equivilent to a function - ideally they should take some input in the form of locals and result in a chunk of HTML.
Related
I'm trying to render a the index view inside my ruby-on-rails application. How do a I render the index view, from inside a view passing an array of things to display? Using the link_to.
I do not want to re-route to the controller, I just want to link_to a view passing it the variables it needs, how can I do this?
EDIT:
I am trying to create a page type functionality in the index of my article model. So I have around 400 articles for example, and when the index action in the article controller is called, it of course renders the index view which is calling a partial for each article in the '#articles array' passed on by article controller's index action.
So in the view, I'm trying to do something like:
<% count = 0 %>
<% #articles.each do |article| %>
<% if count <10 %>
<%= render partial: 'index_articles', locals: {article: article} %>
<% count = count + 1 %>
<% end %>
<% end %>
<% #articles = #articles.drop(10) %>
<% if #articles.any? %>
<%= link_to "Next", 'articles', locals: {#articles => #articles} %>
<% end %>
Thank you in advanced for all of your help.
You'll need to use the render command, probably with a partial:
<%= render "controller/index", collection: ["your", "array"], as: :object_name %>
You will have to call a controller action to generate this. You cannot simply load it on your screen, unless it was preloaded inside your javascript for something:
#View
<%= link_to "Index", controllers_path(ids: ["1","2"]), remote: true %>
#app/controllers/your_controller.rb
class YourController < ApplicationController
def index
#posts = request.xhr? Post.find(params[:ids]) : Post.all
respond_to do |format|
format.js #-> app/views/controller/index.js.erb
format.html
end
end
end
#app/views/controller/index.js.erb
$(".element").html("<%=j render 'index' %>");
There are several issues with this approach...
Flow
First of all, your flow of your app should be as structured as possible.
In short, if you're calling the index view inside another action, it's not the index view any more.
What you should look at is how to use a partial in your app:
#app/controller/views/_partial.html.erb
<%= post.title %>
This way, you can adapt your index view and your other page to use the partial in their respective action layouts:
#app/controller/views/index.html.erb
<%= render "partial", collection: #posts, as: :post %>
This will allow you to "reuse" code much in the way you want. This will be much more appropriate than trying to invoke other action/views.
-
Resources
Secondly, you'll want to look at how your app functions.
Your index view is meant to show all the items for a particular object. Whilst you're free to change this as you want, the fact remains that you have to keep some structure.
You should read up on the routes for your actions, and how they're meant to work in your application. This will give you some perspective on the resourceful nature of Rails routes, and how you'll have to call specific routes with specific actions.
Your problem is probably that the file needs to be named _index.html.erb. You can have another file named index.html.erb which just renders _index.html.erb.
If you need a full guide on using AJAX, look up the railscast. If you're not using AJAX and you just want to render it, then you don't use link_to. You just do <%= render :index %>.
Im trying to bring a layout in my html page by
render layout 'flatty'
thing is this loads the whole flatty layout. In flatty.html.erb it renders _header,_footer and also _sidebar.html.erb
I dont want to load _sidebar.html.erb in this particular page.
So how should i render this?
thing is this loads the whole flatty layout. In flatty.html.erb it renders _header,_footer and also _sidebar.html.erb I dont want to load _sidebar.html.erb in this particular page
Why do you want to use same layout if you have so many changes? Why not make a partial which you could render in both cases. Make a new partial, lets say _common.html.erb, render it in your flatty layout and view of the action in which you want to use it.
#flatty.html.erb
<%= render "common" %>
<%= render "sidebar" %>
#some_action_name.html.erb
<%= render "common" %>
If you still want to use same layout in both cases then you ca use rails 4 controller_name and action_name helpers in your layout and selectively render sidebar and other partials in your layout:
#flatty.html.erb
<%= if controller_name == "some_controller_name" && action_name == "some_action_name"
<%= render "sidebar" %>
<% end %>
Maybe in your controller action, you can have a flag indicating the sidebar should not be rendered. Then, in your flatty.html.erb file, check for the flag variable before you render the _sidebar.html.erb.
For example, if you have a controller action called flatty, add an instance variable, #disable_sidebar, to act as your flag.
def flatty
#disable_sidebar = true
# Your other code
render layout: 'flatty'
end
Then, in your flatty.html.erb, add a conditional before your render for your sidebar (note the ! negation in the if statement:
<% if !#disable_sidebar %>
<%= render "layouts/sidebar" %>
<% end %>
Alternatively, in your flatty.html.erb you can also check for the controller and action values in your params hash, and then don't render your sidebar if it matches that controller's action:
<% if params[:controller]!="YOUR_CONTROLLER" and !params[:action].eql? "flatty" %>
<%= render "layouts/sidebar" %>
<% end %>
I have a partial (_car_grid.html.erb) as follows:
<ul class="car-grid">
<%= render #cars %>
</ul>
Then I wish to call the partial from elsewhere but the instance var I am using is called #car_results. Is there a way to pass in #car_results and have it act as #cars inside the partial?
I have tried:
<%= render 'shared/car_grid', locals: {cars: #car_results} %>
But it doesn't seem to like it.
Any ideas?
You're close. Drop the '#' in your partial so that #cars becomes cars. When you pass in locals to a partial the partial receives local variables, not instance variables.
This means you'll need to change your other invocation of the partial as well to this:
<%= render 'shared/car_grid', locals: {cars: #cars} %>
In your partial, do not use the instance variable. Philip's suggestion is correct.
However, another thing I noticed in your code is that you are using the wrong syntax for rendering the partial. Actually, there are two ways for rendering partial
<%= render partial: "shared/car_grid", locals: {cars: #car_results} %>
or
<%= render "shared/car_grid", cars: #car_results %>
Your code does not contain partial keywords, so you will not need to use locals
Partials
By their nature, Rails partials are not meant to take #instance variables. They are meant to be used in any part of your application, hence why you need to pass local variables to them:
<%= render partial: 'shared/car_grid', locals: { cars: #car_results } %>
A partial is essentially like a code block - where local variables are referenced. This means inside the partial, you'll have to call a local variable, as defined when calling the partial:
#app/views/shared/_car_grid.html.erb
<% cars.each do |car| %>
<%= car.name %>
<% end %>
--
Collections
Some other interesting functionality you should know about is the use of collection when calling a partial.
<%= render partial: "shared/car_grids", collection: #car_results, as: :car %>
This basically works like an each loop - giving you the ability to reload the partial again & again for each member of the collection
I have a resource called Exercises in my application. I currently have a partial called _exercise.html.erb that I use to render them. I have an outlying case where I'd like to render them in a much different way. Can I make another partial for exercises that has this other format and still be able to use <%= render #exercises %>?
If not what is the best approach? Should I out a variable in the controller that tells the partial which layout to use, this would have both layout in one file and one if to decide. Or is there some better way?
If you'd like to use business logic to determine when to show what partial for your #exercises collection you should use the to_partial_path method in the Exercise model to define that. See #4 in this post: http://blog.plataformatec.com.br/2012/01/my-five-favorite-hidden-features-in-rails-3-2/
Or, if this is more of a view-related decision (i.e. one view will always use the regular _exercises.html.erb and another view would always use e.g. _alternate_exercises.html.erb) then you can specify as such:
<%= render partial: 'alternate_exercises', collection: #exercises, as: :exercise %>
This will render the _alternate_exercises.html.erb partial once for each item in #execrises passing the item in to the partial via a local_assign called exercise.
In this case, I suppose you have two options:
1) Put the conditional code inside of _exercises.html.erb
eg.
<% if #exercise.meets_some_condition %>
you see this stuff
<% else %>
you see other stuff
<% end %>
This way, you can still make use of <%= render #exercises %>
2) Otherwise, your other option is to have separate partials and render them outside.
eg.
<% #exercises.each do |exercise| %>
<% if exercise.meets_some_condition %>
<%= render "exercises/some_condition_exercise" %>
<% else %>
<%= render "exercises/exercise" %>
<% end %>
<% end %>
This is the best approach for rendering partial. You can wrap that partial with if else statement in your code. Here is my example
rendering with form called _victim.html.erb
<%= render :partial => "victim", :locals => {:f => f }%>
rendering without form
<%= render :partial => "victim"%>
I have a main layout (application) and two 'sub' layouts (dashboard and admin). In my dashboard and admin controllers respectively I have a before_filter which render templates: the template I want (either dashboard or admin).
In my dashboard and admin layouts, I am doing something along the lines of:
<% content_for :top_menu do %>
<%= render partial: "layouts/menu/top", locals: {section: 'admin'} %>
<%= render partial: "layouts/menu/sub", locals: {section: 'admin'} %>
<% end %>
So this is including the top partials with a section local which shows the correct options I want.
In my application layout, I have the following:
SOME HTML HERE
<%= yield :top_menu %>
SOME HTML HERE
<%= yield %>
SOME HTML HERE
The problem is that the content from my views isn't being displayed, I'd expect it to be displayed where the 'yield' is in my application layout.
I have read: http://guides.rubyonrails.org/layouts_and_rendering.html#using-nested-layouts - but following that just displays the menus twice and still doesn't display my content.
I think I am failing to understand something here, help would be appreciated.
In short, I want top menus and it's in the controller that I want to specify which menu is to be used. I'm sure there is a better solution to this that I am missing also.
I have fixed this by doing:
layout 'menu/admin'
In my controller, and adding:
<%= render template: "layouts/application" %>
To my layouts.