bootstrap_form is a Rails form builder that makes it super easy to integrate Bootstrap v4-style forms into your Rails application.
- Ruby 2.2.2+
- Rails 5.0+ (Rails 5.1+ for
bootstrap_form_with) - Bootstrap 4.0.0+
Add it to your Gemfile:
gem "bootstrap_form", ">= 4.0.0"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">
<input name="user[remember_me]" type="hidden" value="0">
<input class="form-check-input" id="user_remember_me" name="user[remember_me]" type="checkbox" value="1">
<label class="form-check-label" for="user_remember_me">Remember me</label>
</div>
<input class="btn btn-secondary" name="commit" type="submit" value="Log In">
</form>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: '[email protected]' %>
<%= f.submit %>
<% end %>Note that form_with in Rails 5.1 does not add IDs to form elements and labels by default, which are both important to Bootstrap markup. This behavior is corrected in Rails 5.2.
To get started, just use the bootstrap_form_with helper in place of form_with. Here's an example:
<%= bootstrap_form_with(model: @user, local: true) do |f| %>
<%= f.email_field :email %>
<%= f.password_field :password %>
<%= f.check_box :remember_me %>
<%= f.submit "Log In" %>
<% end %>This generates:
<form role="form" action="/users" accept-charset="UTF-8" method="post">
<input name="utf8" type="hidden" value="✓" />
<div class="form-group">
<label class="required" for="user_email">Email</label>
<input class="form-control" type="email" value="[email protected]" name="user[email]" />
</div>
<div class="form-group">
<label for="user_password">Password</label>
<input class="form-control" type="password" name="user[password]" />
<small class="form-text text-muted">A good password should be at least six characters long</small>
</div>
<div class="form-check">
<input name="user[remember_me]" type="hidden" value="0">
<input class="form-check-input" id="user_remember_me" name="user[remember_me]" type="checkbox" value="1">
<label class="form-check-label" for="user_remember_me">Remember me</label>
</div>
<input type="submit" name="commit" value="Log In" class="btn btn-secondary" data-disable-with="Log In" />
</form>bootstrap_form_with supports both the model: and url: use cases
in form_with.
form_with has some important differences compared to form_for and form_tag, and these differences apply to bootstrap_form_with. A good summary of the differences can be found at: https://m.patrikonrails.com/rails-5-1s-form-with-vs-old-form-helpers-3a5f72a8c78a, or in the Rails documentation.
The Rails team has suggested that form_for and form_tag may be deprecated and then removed in future versions of Rails. bootstrap_form will continue to support bootstrap_form_for and bootstrap_form_tag as long as Rails supports form_for and form_tag.
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
- submit
- button
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" %>Or you can add the label as input placeholder instead (this automatically hides the label):
<%= f.text_field :email, label_as_placeholder: true %>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 required option to force the class to be present or absent:
<%= f.password_field :login, label: "New Username", required: true %>
<%= f.password_field :password, label: "New Password", required: false %>To specify the class of the generated input tag, 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"Help translations containing HTML should follow the convention of appending _html to the name:
en:
activerecord:
help:
user:
password_html: "A <strong>good</strong> 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.
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 the :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, [["Apple", 1], ["Grape", 2]], { label: "Choose your favorite fruit:" }, { class: "selectpicker", wrapper: { class: 'has-warning', data: { foo: 'bar' } } } %>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 %>Check boxes and radio buttons are wrapped in a div.form-check. You can add classes to this div with the :wrapper_class option:
<%= f.radio_button :skill_level, 0, label: "Novice", inline: true, wrapper_class: "w-auto" %>bootstrap_form also provides helpers that automatically create 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 theform_group's label:hide_label: Pass true to hide theform_group's label:help: Add a help span to theform_group- Other options will be forwarded to the
radio_button/check_boxmethod
You can create a static control like this:
<%= f.static_control :email %>Here's the output for a horizontal layout:
<div class="form-group">
<label class="col-sm-2 form-control-label" for="user_email">Email</label>
<div class="col-sm-10">
<input class="form-control-plaintext" id="user_email" name="user[email]" readonly="readonly" type="text" value="[email protected]"/>
</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 styles our controls as blocks. This wrapper fixes
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 the primary helper receives a render_as_button: true option or a block,
it will be rendered as an HTML button, instead of an input tag. This allows you
to specify HTML content and styling for your buttons (such as adding
illustrative icons to them). For example, the following statements
<%= f.primary "Save changes <span class='fa fa-save'></span>".html_safe, render_as_button: true %>
<%= f.primary do
concat 'Save changes '
concat content_tag(:span, nil, class: 'fa fa-save')
end %>are equivalent, and each of them both be rendered as
<button name="button" type="submit" class="btn btn-primary">Save changes <span class="fa fa-save"></span></button>If you wish to add additional CSS classes to your button, while keeping the
default ones, you can use the extra_class option. This is particularly useful
for adding extra details to buttons (without forcing you to repeat the
Bootstrap classes), or for element targeting via CSS classes.
Be aware, however, that using the class option will discard any extra classes
you add. As an example, the following button declarations
<%= f.primary "My Nice Button", extra_class: 'my-button' %>
<%= f.primary "My Button", class: 'my-button' %>will be rendered as
<input type="submit" value="My Nice Button" class="btn btn-primary my-button" />
<input type="submit" value="My Button" class="my-button" />(some unimportant HTML attributes have been removed for simplicity)
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 %>Control col wrapper class can be modified with add_control_col_class. This option will preserve column definition:
<%= bootstrap_form_for(@user, layout: :horizontal) do |f| %>
<%= f.email_field :email %>
<%= f.text_field :age, add_control_col_class: "additional-control-col-class" %>
<%= f.form_group do %>
<%= f.submit %>
<% end %>
<% end %>The form-level layout can be overridden per field, unless the form-level layout was inline:
<%= 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 %>A form-level layout: :inline can't be overridden because of the way Bootstrap 4 implements in-line layouts. One possible work-around is to leave the form-level layout as default, and specify the individual fields as layout: :inline, except for the fields(s) that should be other than in-line.
The custom option can be used to replace the browser default styles for check boxes and radio buttons with dedicated Bootstrap styled form elements. Here's an example:
<%= bootstrap_form_for(@user) do |f| %>
<%= f.email_field :email %>
<%= f.password_field :password %>
<%= f.check_box :remember_me, custom: true %>
<%= f.submit "Log In" %>
<% end %>By default, fields that have validation errors will be 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">
<label class="form-control-label" for="user_email">Email</label>
<input class="form-control is-invalid" id="user_email" name="user[email]" type="email" value="">
<small class="invalid-feedback">can't be blank</small>
</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
By their very nature, forms are extremely diverse. It would be extremely difficult to provide a gem that could handle every need. Here are some tips for handling edge cases.
Some third party plug-ins require an empty but visible label on an input control. The hide_label option generates a label that won't appear on the screen, but it's considered invisible and therefore doesn't work with such a plug-in. An empty label (e.g. "") causes the underlying Rails helper to generate a label based on the field's attribute's name.
The solution is to use a zero-width character for the label, or some other "empty" HTML. For example:
label: "​".html_safe
or
label: "<span></span>".html_safe
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)