I was reading code of linuxfr.org, a rails open source project. I am surprised that the following code from application.html.haml does not have a "yield" statement (without any symbol associated with it), so how will the content be rendered with the layout?
https://github.com/linuxfrorg/linuxfr.org/blob/master/app/views/layouts/application.html.haml
For example, how does the layout merge with the show view file?
https://github.com/linuxfrorg/linuxfr.org/blob/master/app/views/wiki_pages/show.html.haml
By default, yield is the same as yield :layout. Rails assumes that all code inside view files are content_for :layout if not specified otherwise.
Related
I have an SVG file that's part of a template located at:
vendor/theme/assets/icons/icon-1.svg
How do I render that inline in my view? render partial: path fails and says it can't find a partial.
In your view insert the following:
<%= render inline: Rails.root.join('vendor/theme/assets/icons/icon-1.svg').read %>
If you're going to be doing this multiple times, you may want to refactor this into a helper.
Also, think about the following:
Are you okay with dumping third party code directly into your view?
Is the vendor SVG file updated automatically without review?
Are you sure the vendor SVG file will never contain malicious code?
I understand that .html.erb files go within app/views or its subfolders. But what is the app/views/layouts folder in particular for in Rails?
app/views/layouts is the folder in which rails looks for the layouts.
From http://guides.rubyonrails.org/layouts_and_rendering.html#finding-layouts :
To find the current layout, Rails first looks for a file in
app/views/layouts with the same base name as the controller. For
example, rendering actions from the PhotosController class will use
app/views/layouts/photos.html.erb (or
app/views/layouts/photos.builder). If there is no such
controller-specific layout, Rails will use
app/views/layouts/application.html.erb or
app/views/layouts/application.builder. If there is no .erb layout,
Rails will use a .builder layout if one exists. Rails also provides
several ways to more precisely assign specific layouts to individual
controllers and actions.
What is a layout?
A layout defines the surroundings of an HTML page. It's the place to define common look and feel of the page.
The RailsCasts episode - All About Layouts - though very old, is still very useful in this context.
Layout in rails framework is very important folder, main layout of your application is define here as application.html.erb and all the views are yielded here using <% yield %>
I'm not sure if this is convention or not, but I have been working through Hartl's Rails tutorial and I noticed that he creates all his partial files with a leading underscore. For example _user.html.erb. Is this something that is necessary for the partial to work, or is this a stylistic choice?
It's necessary for partials to work. From the official Rails guide:
3.4.1 Naming Partials
To render a partial as part of a view, you use the render method within the view:
<%= render "menu" %>
This will render a file named _menu.html.erb at that point within the view being rendered. Note the leading underscore character: partials are named with a leading underscore to distinguish them from regular views, even though they are referred to without the underscore. This holds true even when you're pulling in a partial from another folder:
Ok, I realise this question has been asked many times but the answers never seems to address the issue/question I have with this.
I have a js file that I would like to include on specific pages only. There are many responses that suggest that I put files into folders and then in the manifest file reference only those folders - for example this Railscast (at about 06:20) talks about this.
However, I only have one application layout file (and I guess this could be the area I'm lacking in) - therefore this file points to the application.js manifest and therefore I can't see how I can include things conditionally.
It's a bit like this resource too - http://railsapps.github.io/rails-javascript-include-external.html - scroll down to the page-specific scripts sub heading and it repeats what the Railscast suggests. But nothing is mentioned of multiple application layout files.
If anyone can help me clarify what to do in this situation I would be most grateful.
I should perhaps point out that I'm using Rails 4.
You can use content_for in your views to "inject" content into the layout when said view is to be rendered. See: using-the-content-for-method
You'd need to do a few things to make this happen:
Add the placeholder to yield the content in the layout. ex.
<%= yield :js %>
Add the block (to be yielded) to your view. ex:
<%= content_for :js do %>
<%= javascript_include_tag "my_script" %>
<% end %>
If you are using the asset pipeline in production and you want to reference a particular asset like a "my_script.js", in your production.rb or relevant environment config.you will need to precompile it using:
config.assets.precompile=["my_script.js"]
In application.html.erb, use this to add controller specific javascript instead of application specific javascript. Make sure you remove require_tree.
<%= javascript_include_tag params[:controller] %>
Read more on this topic on Rails Guide.
Well since I am using a lot of helper methods in my view files and I avoid using html in most of my view files.
Example
myview.html.erb
<%=myhelper #myobject%>
so I end up using,the erb processing tags each time for each file.
<%=%>
I want to register .rb as a template handler or any other extention for that matter.
So my templates look like
myview.html.rb
myhelper #myobject
I am clueless on how to go ahead.
I found it,it seems railscasts already covered that part.
Its show notes,worth checking out.
https://github.com/railscasts/379-template-handlers/blob/master/store-after/config/initializers/ruby_template_handler.rb
Things without ruby are easy to read and render without those erb tags.