Show error in field instead of flash/notice

Question

I have a Rails application with Twitter Bootstrap that, when creating a record and presenting errors, shows the error in a flash/notice as per image:

However, I would like errors to appear in the fields, and change the class of inputs to . has-error or something like that. I took a look at field_error_proc and tried to change it in several ways, but to no avail (actually, maybe I did something wrong).

Answer 1

Using the form helpers

<%= form_for @post |f| %>
  <% @post.errors[:title].join(", ") %>
  <%= f.text_field :title %>
  <%= f.submit "Create" %>
<% end %>

error fields have an output like this:

<div class="field_with_errors">
 <input id="post_title" name="post[title]" size="30" type="text" value="">
</div>

using the class field_with_errors:

.field_with_errors {
  padding: 2px;
  background-color: red;
  display: table;
}

source

Answer 2

In the case of Bootstrap, it is possible to make the border of fields with a red error with a simple line in jQuery:

$(".form-group:has(.field_with_errors)").addClass("has-error");