⚠️ This documentation is for the master branch, which is not yet stable and targets Bootstrap v4. If you are using Bootstrap v3, refer to the stable legacy-2.7 branch.

bootstrap_form is a Rails form builder that makes it super easy to integrate Bootstrap v4-style forms into your Rails application.

• Ruby 2.3+
• Rails 5.0+
• Bootstrap 4.0.0-beta.3+

Add it to your Gemfile:

gem "bootstrap_form",
    git: "https://github.com/bootstrap-ruby/rails-bootstrap-forms.git",
    branch: "master"

Then:

bundle

Then require the CSS in your application.css file:

/*
 *= require rails_bootstrap_forms
 */

To get started, just use the bootstrap_form_for helper. Here's an example:

<%= bootstrap_form_for(@user) do |f| %>
  <%= f.email_field :email %>
  <%= f.password_field :password %>
  <%= f.check_box :remember_me %>
  <%= f.submit "Log In" %>
<% end %>

This generates the following HTML:

<form accept-charset="UTF-8" action="/users" class="new_user" id="new_user" method="post">
  <div class="form-group">
    <label for="user_email">Email</label>
    <input class="form-control" id="user_email" name="user[email]" type="email">
  </div>
  <div class="form-group">
    <label for="user_password">Password</label>
    <input class="form-control" id="user_password" name="user[password]" type="password">
  </div>
  <div class="form-check">
    <label for="user_remember_me">
      <input name="user[remember_me]" type="hidden" value="0">
      <input id="user_remember_me" name="user[remember_me]" type="checkbox" value="1"> Remember me
    </label>
  </div>
  <input class="btn btn-secondary" name="commit" type="submit" value="Log In">
</form>

In order to active nested_form support, use bootstrap_nested_form_for instead of bootstrap_form_for.

If your form is not backed by a model, use the bootstrap_form_tag. Usage of this helper is the same as bootstrap_form_for, except no model object is passed in as the first argument. Here's an example:

<%= bootstrap_form_tag url: '/subscribe' do |f| %>
  <%= f.email_field :email, value: 'name@example.com' %>
  <%= f.submit %>
<% end %>

This gem wraps the following Rails form helpers:

• check_box
• collection_check_boxes
• collection_select
• color_field
• date_field
• date_select
• datetime_field
• datetime_local_field
• datetime_select
• email_field
• file_field
• grouped_collection_select
• hidden_field (not wrapped, but supported)
• month_field
• number_field
• password_field
• phone_field
• radio_button
• collection_radio_buttons
• range_field
• search_field
• select
• telephone_field
• text_area
• text_field
• time_field
• time_select
• time_zone_select
• url_field
• week_field

These helpers accept the same options as the standard Rails form helpers, with a few extra options:

Use the label option if you want to specify the field's label text:

<%= f.password_field :password_confirmation, label: "Confirm Password" %>

To hide a label, use the hide_label: true option. This adds the sr-only class, which keeps your labels accessible to those using screen readers.

<%= f.text_area :comment, hide_label: true, placeholder: "Leave a comment..." %>

To add custom classes to the field's label:

<%= f.text_field :email, label_class: "custom-class" %>

A label that is associated with a required field is automatically annotated with a required CSS class. You are free to add any appropriate CSS to style required fields as desired. One example would be to automatically add an asterisk to the end of the label:

label.required:after {
  content:" *";
}

The label required class is determined based on the definition of a presence validator with the associated model attribute. Presently this is one of: ActiveRecord::Validations::PresenceValidator or ActiveModel::Validations::PresenceValidator.

In cases where this behavior is undesirable, use the skip_required option:

<%= f.password_field :password, label: "New Password", skip_required: true %>

To specify the class of the generated input, use the control_class option:

<%= f.text_field :email, control_class: "custom-class" %>

To add help text, use the help option:

<%= f.password_field :password, help: "Must be at least 6 characters long" %>

This gem is also aware of help messages in locale translation files (i18n):

en:
  activerecord:
    help:
      user:
        password: "A good password should be at least six characters long"

If your model name has multiple words (like SuperUser), the key on the translation file should be underscored (super_user).

You can override help translations for a particular field by passing the help option or turn them off completely by passing help: false.

To add an icon to a field, use the icon option and pass the icon name without the 'glyphicon' prefix:

<%= f.text_field :login, icon: "user" %>

This automatically adds the has-feedback class to the form-group:

<div class="form-group has-feedback">
  <label class="form-control-label" for="user_login">Login</label>
  <input class="form-control" id="user_login" name="user[login]" type="text" />
  <span class="glyphicon glyphicon-user form-control-feedback"></span>
</div>

You can pass prepend and/or append options to input fields:

<%= f.text_field :price, prepend: "$", append: ".00" %>

You can also prepend and append buttons. Note: The buttons must contain the btn class to generate the correct markup.

<%= f.text_field :search, append: link_to("Go", "#", class: "btn btn-secondary") %>

To add a class to the input group wrapper, use :input_group_class option.

<%= f.email_field :email, append: f.primary('Subscribe'), input_group_class: 'input-group-lg' %>

If you want to add an additional css class or any other attribute to the form group div, you can use the wrapper: { class: 'additional-class', data: { foo: 'bar' } } option.

<%= f.text_field :name, wrapper: { class: 'has-warning', data: { foo: 'bar' } } %>

Which produces the following output:

<div class="form-group has-warning" data-foo="bar">
  <label class="form-control-label" for="user_name">Id</label>
  <input class="form-control" id="user_name" name="user[name]" type="text">
</div>

You still can use wrapper_class option to set only a css class. This is just a short form of wrapper: { class: 'additional-class' }.

Our select helper accepts the same arguments as the default Rails helper. Here's an example of how you pass both options and html_options hashes:

<%= f.select :product, [[1, "Apple"], [2, "Grape"]], { label: "Choose your favorite fruit:" }, { class: "selectpicker" } %>

Checkboxes and radios should be placed inside of a form_group to render properly. The following example ensures that the entire form group will display an error if an associated validations fails:

<%= f.form_group :skill_level, label: { text: "Skill" }, help: "Optional Help Text" do %>
  <%= f.radio_button :skill_level, 0, label: "Novice", checked: true %>
  <%= f.radio_button :skill_level, 1, label: "Intermediate" %>
  <%= f.radio_button :skill_level, 2, label: "Advanced" %>
<% end %>

<%= f.form_group :terms do %>
  <%= f.check_box :terms, label: "I agree to the Terms of Service" %>
<% end %>

You can also create a checkbox using a block:

<%= f.form_group :terms, label: { text: "Optional Label" } do %>
  <%= f.check_box :terms do %>
    You need to check this box to accept our terms of service and privacy policy
  <% end %>
<% end %>

To display checkboxes and radios inline, pass the inline: true option:

<%= f.form_group :skill_level, label: { text: "Skill" } do %>
  <%= f.radio_button :skill_level, 0, label: "Novice", inline: true %>
  <%= f.radio_button :skill_level, 1, label: "Intermediate", inline: true %>
  <%= f.radio_button :skill_level, 2, label: "Advanced", inline: true %>
<% end %>

BootstrapForms also provides helpers that automatically creates the form_group and the radio_buttons or check_boxes for you:

<%= f.collection_radio_buttons :skill_level, Skill.all, :id, :name %>
<%= f.collection_check_boxes :skills, Skill.all, :id, :name %>

Collection methods accept these options:

• :label: Customize the form_group's label
• :hide_label: Pass true to hide the form_group's label
• :help: Add a help span to the form_group
• Other options will be forwarded to the radio_button/check_box method

You can create a static control like this:

<%= f.static_control :email %>

Here's the output:

<div class="form-group">
  <label class="col-sm-2 form-control-label" for="user_email">Email</label>
  <div class="col-sm-10">
    <p class="form-control-static">test@email.com</p>
  </div>
</div>

You can also create a static control that isn't based on a model attribute:

<%= f.static_control label: "Custom Static Control" do %>
  Content Here
<% end %>

The multiple selects that the date and time helpers (date_select, time_select, datetime_select) generate are wrapped inside a div.rails-bootstrap-forms-[date|time|datetime]-select tag. This is because Bootstrap automatically stylizes ours controls as blocks. This wrapper fix this defining these selects as inline-block and a width of auto.

The btn btn-secondary css classes are automatically added to your submit buttons.

<%= f.submit %>

You can also use the primary helper, which adds btn btn-primary to your submit button:

<%= f.primary "Optional Label" %>

You can specify your own classes like this:

<%= f.submit "Log In", class: "btn btn-success" %>

If you want to use the original Rails form helpers for a particular field, append _without_bootstrap to the helper:

<%= f.text_field_without_bootstrap :email %>

By default, your forms will stack labels on top of controls and your controls will grow to 100% of the available width.

To use an inline-layout form, use the layout: :inline option. To hide labels, use the hide_label: true option, which keeps your labels accessible to those using screen readers.

<%= bootstrap_form_for(@user, layout: :inline) do |f| %>
  <%= f.email_field :email, hide_label: true %>
  <%= f.password_field :password, hide_label: true %>
  <%= f.check_box :remember_me %>
  <%= f.submit %>
<% end %>

To skip label rendering at all, use skip_label: true option.

<%= f.password_field :password, skip_label: true %>

To use a horizontal-layout form with labels to the left of the control, use the layout: :horizontal option. You should specify both label_col and control_col css classes as well (they default to col-sm-2 and col-sm-10).

In the example below, the checkbox and submit button have been wrapped in a form_group to keep them properly aligned.

<%= bootstrap_form_for(@user, layout: :horizontal, label_col: "col-sm-2", control_col: "col-sm-10") do |f| %>
  <%= f.email_field :email %>
  <%= f.password_field :password %>
  <%= f.form_group do %>
    <%= f.check_box :remember_me %>
  <% end %>
  <%= f.form_group do %>
    <%= f.submit %>
  <% end %>
<% end %>

The label_col and control_col css classes can also be changed per control:

<%= bootstrap_form_for(@user, layout: :horizontal) do |f| %>
  <%= f.email_field :email %>
  <%= f.text_field :age, control_col: "col-sm-3" %>
  <%= f.form_group do %>
    <%= f.submit %>
  <% end %>
<% end %>

The layout can be overridden per field:

<%= bootstrap_form_for(@user, layout: :horizontal) do |f| %>
  <%= f.email_field :email %>
  <%= f.text_field :feet, layout: :default %>
  <%= f.text_field :inches, layout: :default %>
  <%= f.form_group do %>
    <%= f.submit %>
  <% end %>
<% end %>

By default, fields that have validation errors will outlined in red and the error will be displayed below the field. Rails normally wraps the fields in a div (field_with_errors), but this behavior is suppressed. Here's an example:

<div class="form-group has-danger">
  <label class="form-control-label" for="user_email">Email</label>
  <input class="form-control" id="user_email" name="user[email]" type="email" value="">
  <span class="form-control-feedback">can't be blank</span>
</div>

You can turn off inline errors for the entire form like this:

<%= bootstrap_form_for(@user, inline_errors: false) do |f| %>
  ...
<% end %>

You can also display validation errors in the field's label; just turn on the :label_errors option. Here's an example:

<%= bootstrap_form_for(@user, label_errors: true) do |f| %>
  ...
<% end %>

By default, turning on :label_errors will also turn off :inline_errors. If you want both turned on, you can do that too:

<%= bootstrap_form_for(@user, label_errors: true, inline_errors: true) do |f| %>
  ...
<% end %>

To display an error message with an error summary, you can use the alert_message helper. This won't output anything unless a model validation has failed.

<%= f.alert_message "Please fix the errors below." %>

Which outputs:

<div class="alert alert-danger">
  <p>Please fix the errors below.</p>
  <ul class="rails-bootstrap-forms-error-summary">
    <li>Email can't be blank</li>
  </ul>
</div>

You can turn off the error summary like this:

<%= f.alert_message "Please fix the errors below.", error_summary: false %>

To output a simple unordered list of errors, use the error_summary helper.

<%= f.error_summary %>

Which outputs:

<ul class="rails-bootstrap-forms-error-summary">
  <li>Email can't be blank</li>
</ul>

If you want to display a custom inline error for a specific attribute not represented by a form field, use the errors_on helper.

<%= f.errors_on :tasks %>

Which outputs:

<div class="alert alert-danger">Tasks can't be blank.</div>

You can hide the attribute name like this:

<%= f.errors_on :tasks, hide_attribute_name: true %>

Which outputs:

<div class="alert alert-danger">can't be blank.</div>

bootstrap_form follows standard rails conventions so it's i18n-ready. See more here: http://guides.rubyonrails.org/i18n.html#translations-for-active-record-models

http://www.codetriage.com/potenza/bootstrap_form

We welcome contributions. If you're considering contributing to bootstrap_form, please review the Contributing document first.

MIT License. Copyright 2012-2018 Stephen Potenza (https://github.com/potenza)