class Formtastic::Inputs::RangeInput

Outputs a simple `<label>` with a HTML5 `<input type=“range”>` wrapped in the standard `<li>` wrapper. This is an alternative input choice to a number input.

Sensible default for the `min`, `max` and `step` attributes are found by reflecting on the model's validations. When validations are not provided, the `min` and `step` default to `1` and the `max` default to `100`. An `IndeterminableMinimumAttributeError` exception will be raised when the following conditions are all true:

• you haven't specified a `:min` or `:max` for the input

• the model's database column type is a `:float` or `:decimal`

• the validation uses `:less_than` or `:greater_than`

The solution is to either:

• manually specify the `:min` or `:max` for the input

• change the database column type to an `:integer` (if appropriate)

• change the validations to use `:less_than_or_equal_to` or `:greater_than_or_equal_to`

@example Full form context and output

<%= semantic_form_for(@user) do |f| %>
  <%= f.inputs do %>
    <%= f.input :shoe_size, :as => :range %>
  <% end %>
<% end %>

<form...>
  <fieldset>
    <ol>
      <li class="numeric">
        <label for="user_shoe_size">Shoe size</label>
        <input type="range" id="user_shoe_size" name="user[shoe_size]" min="1" max="100" step="1">
      </li>
    </ol>
  </fieldset>
</form>

@example Default HTML5 min/max/step attributes are detected from the numericality validations

class Person < ActiveRecord::Base
  validates_numericality_of :age, 
    :less_than_or_equal_to => 100, 
    :greater_than_or_equal_to => 18, 
    :only_integer => true
end

<%= f.input :age, :as => :number %>

<li class="numeric">
  <label for="persom_age">Age</label>
  <input type="range" id="person_age" name="person[age]" min="18" max="100" step="1">
</li>

@example Pass attributes down to the `<input>` tag with :input_html

<%= f.input :shoe_size, :as => :range, :input_html => { :min => 3, :max => 15, :step => 1, :class => "special" } %>

@example Min/max/step also work as options

<%= f.input :shoe_size, :as => :range, :min => 3, :max => 15, :step => 1, :input_html => { :class => "special" } %>

@example Use :in with a Range as a shortcut for :min/:max

<%= f.input :shoe_size, :as => :range, :in => 3..15, :step => 1 %>
<%= f.input :shoe_size, :as => :range, :input_html => { :in => 3..15, :step => 1 } %>

@see Formtastic::Helpers::InputsHelper#input InputsHelper#input for full documentation of all possible options. @see api.rubyonrails.org/classes/ActiveModel/Validations/HelperMethods.html#method-i-validates_numericality_of Rails' Numericality validation documentation