Rails Devise I18n Flash Messages with Twitter Bootstrap
I made a wiki page within the devise wiki on github for How To: Integrate I18n Flash Messages with Devise and Bootstrap
Flash Messages For the Site
First we will make a rendered view to make the code concise. Within "app/views/layouts/application.html.erb" I added <%= render 'layouts/messages' %>.
My file looks like:
<body>
<%= render 'layouts/header' %>
<div class="container">
<%= render 'layouts/messages' %>
<%= yield %>
<%= render 'layouts/footer' %>
</div>
</body>
Next we have to make the messages file. Make a new file in "app/views/layouts/_messages.html.erb" and add:
<% flash.each do |key, value| %>
<div class="alert alert-<%= key %>">
<a href="#" data-dismiss="alert" class="close">×</a>
<ul>
<li>
<%= value %>
</li>
</ul>
</div>
<% end %>
This will give us flash messages for the entire site.
Flash Messages For Devise
For devise you need to override the way devise handles flash messages. Create a file called devise_helper in "app/helpers/devise_helper.rb".
Inside the file you have to create a method called devise_error_messages!, which is the name of the file that tells devise how to handle flash messages.
module DeviseHelper
def devise_error_messages!
return '' if resource.errors.empty?
messages = resource.errors.full_messages.map { |msg| content_tag(:li, msg) }.join
html = <<-HTML
<div class="alert alert-error alert-block"> <button type="button"
class="close" data-dismiss="alert">x</button>
#{messages}
</div>
HTML
html.html_safe
end
end
Next in your devise views you will have to define where you want the error messages to appear. You will need to enter <%= devise_error_messages! %> within the devise pages. An example is entering this within "app/views/devise/registrations/.new.html.erb" (The sign up page)
It should already be within the file, but you can move the code around to customize where it is shown.
CSS For Flash Messages
If you do not want to use the odd blue and yellow alerts that come default, I have set error and alert to have the same colorand success and notice to have the same color. I am using red for errors and alerts, and green for success and notice.
Within my "app/assets/stylesheets/custom.css.scss" I have:
/*flash*/
.alert-error {
background-color: #f2dede;
border-color: #eed3d7;
color: #b94a48;
text-align: left;
}
.alert-alert {
background-color: #f2dede;
border-color: #eed3d7;
color: #b94a48;
text-align: left;
}
.alert-success {
background-color: #dff0d8;
border-color: #d6e9c6;
color: #468847;
text-align: left;
}
.alert-notice {
background-color: #dff0d8;
border-color: #d6e9c6;
color: #468847;
text-align: left;
}
The simplest solution I've found is to use a common partial for all flash messages while checking for :notice and :alertto replace with the necessary bootstrap class.
So make /views/shared/_alerts.html.erb like this -
<% flash.each do |message_type, message| %>
<div class="alert alert-<%= flash_class_name(message_type) %> alert-dismissable">
<span><%= message %></span>
<button type="button" class="close" data-dismiss="alert" aria-label="Close">
<span aria-hidden="true">×</span>
</button>
</div>
<% end %>
Add a helper method (I've added it to the application helper) like this -
def flash_class_name(name)
case name
when "notice" then "success"
when "alert" then "danger"
else name
end
end
Include _alerts.html.erb in the application layout (or the parent layout for your application).
That's it!
If you use Sass in your app, you can extend BS classes alert-info and alert-danger with Devise's alert-notice and alert-alert respectively, in a way like this:
.alert-notice {
@extend .alert-info
}
.alert-alert {
@extend .alert-danger
}
By adding this to your *.scss, Devise flash messages will inherit the styles of BS info and danger alerts.
http://sass-lang.com/guide (Extend/Inheritance section)
Here's my 2 cents.
Using a case statement to check if the flash names are the older syntax alertor notice and change them to success or danger if they are and leave everything else alone.
<div class="container">
<% flash.each do |name, msg| %>
<% if msg.is_a?(String) %>
<div class="alert alert-<%= flash_class_name(name) %>" role="alert">
<button type="button" class="close" data-dismiss="alert"><span aria-hidden="true">×</span>
<span class="sr-only">Close</span>
</button>
<%= content_tag :div, msg, :id => "flash_#{name}" %>
</div>
<% end %>
<% end %>
</div>
and a helper method
def flash_class_name(name)
case name
when 'notice' then 'success'
when 'alert' then 'danger'
else name
end
end