title: How to use placeholders instead of labels in simple_form?
body: <p>I want to use placeholders everywhere in my application instead of labels. I am using simple_form and Rails (3.2.14). How can I specify in simple_form config file to use placeholders instead of labels.</p>
  
  <p>In Initializers there is a file simple_form.rb ie</p>
  
  <pre><code># Use this setup block to configure all options available in SimpleForm.
  SimpleForm.setup do |config|
    # Wrappers are used by the form builder to generate a
    # complete input. You can remove any component from the
    # wrapper, change the order or even add your own to the
    # stack. The options given below are used to wrap the
    # whole input.
    config.wrappers :default, :class =&gt; :input, :hint_class =&gt; :field_with_hint, :error_class =&gt; :field_with_errors do |b|
      ## Extensions enabled by default
      # Any of these extensions can be disabled for a
      # given input by passing: `f.input EXTENSION_NAME =&gt; false`.
      # You can make any of these extensions optional by
      # renaming `b.use` to `b.optional`.
  
      # Determines whether to use HTML5 (:email, :url, ...)
      # and required attributes
      b.use :html5
  
      # Calculates placeholders automatically from I18n
      # You can also pass a string as f.input :placeholder =&gt; "Placeholder"
      b.use :placeholder
  
      ## Optional extensions
      # They are disabled unless you pass `f.input EXTENSION_NAME =&gt; :lookup`
      # to the input. If so, they will retrieve the values from the model
      # if any exists. If you want to enable the lookup for any of those
      # extensions by default, you can change `b.optional` to `b.use`.
  
      # Calculates maxlength from length validations for string inputs
      b.optional :maxlength
  
      # Calculates pattern from format validations for string inputs
      b.optional :pattern
  
      # Calculates min and max from length validations for numeric inputs
      b.optional :min_max
  
      # Calculates readonly automatically from readonly attributes
      b.optional :readonly
  
      ## Inputs
      b.use :label_input
      b.use :hint,  :wrap_with =&gt; { :tag =&gt; :span, :class =&gt; :hint }
      b.use :error, :wrap_with =&gt; { :tag =&gt; :span, :class =&gt; :error }
    end
  
    # The default wrapper to be used by the FormBuilder.
    config.default_wrapper = :default
  
    # Define the way to render check boxes / radio buttons with labels.
    # Defaults to :nested for bootstrap config.
    #   :inline =&gt; input + label
    #   :nested =&gt; label &gt; input
    config.boolean_style = :nested
  
    # Default class for buttons
    config.button_class = 'btn'
  
    # Method used to tidy up errors. Specify any Rails Array method.
    # :first lists the first message for each field.
    # Use :to_sentence to list all errors for each field.
    # config.error_method = :first
  
    # Default tag used for error notification helper.
    config.error_notification_tag = :div
  
    # CSS class to add for error notification helper.
    config.error_notification_class = 'alert alert-error'
  
    # ID to add for error notification helper.
    # config.error_notification_id = nil
  
    # Series of attempts to detect a default label method for collection.
    # config.collection_label_methods = [ :to_label, :name, :title, :to_s ]
  
    # Series of attempts to detect a default value method for collection.
    # config.collection_value_methods = [ :id, :to_s ]
  
    # You can wrap a collection of radio/check boxes in a pre-defined tag, defaulting to none.
    # config.collection_wrapper_tag = nil
  
    # You can define the class to use on all collection wrappers. Defaulting to none.
    # config.collection_wrapper_class = nil
  
    # You can wrap each item in a collection of radio/check boxes with a tag,
    # defaulting to :span. Please note that when using :boolean_style = :nested,
    # SimpleForm will force this option to be a label.
    # config.item_wrapper_tag = :span
  
    # You can define a class to use in all item wrappers. Defaulting to none.
    # config.item_wrapper_class = nil
  
    # How the label text should be generated altogether with the required text.
    # config.label_text = lambda { |label, required| "#{required} #{label}" }
  
    # You can define the class to use on all labels. Default is nil.
    config.label_class = 'control-label'
  
    # You can define the class to use on all forms. Default is simple_form.
    # config.form_class = :simple_form
  
    # You can define which elements should obtain additional classes
    # config.generate_additional_classes_for = [:wrapper, :label, :input]
  
    # Whether attributes are required by default (or not). Default is true.
    # config.required_by_default = true
  
    # Tell browsers whether to use default HTML5 validations (novalidate option).
    # Default is enabled.
    config.browser_validations = false
  
    # Collection of methods to detect if a file type was given.
    # config.file_methods = [ :mounted_as, :file?, :public_filename ]
  
    # Custom mappings for input types. This should be a hash containing a regexp
    # to match as key, and the input type that will be used when the field name
    # matches the regexp as value.
    # config.input_mappings = { /count/ =&gt; :integer }
  
    # Custom wrappers for input types. This should be a hash containing an input
    # type as key and the wrapper that will be used for all inputs with specified type.
    # config.wrapper_mappings = { :string =&gt; :prepend }
  
    # Default priority for time_zone inputs.
    # config.time_zone_priority = nil
  
    # Default priority for country inputs.
    # config.country_priority = nil
  
    # Default size for text inputs.
    # config.default_input_size = 50
  
    # When false, do not use translations for labels.
    # config.translate_labels = true
  
    # Automatically discover new inputs in Rails' autoload path.
    # config.inputs_discovery = true
  
    # Cache SimpleForm inputs discovery
    # config.cache_discovery = !Rails.env.development?
  end
  </code></pre>