Question

I have a simple_form which I am trying to get to always include a blank item in it, as a ‘nil’ value in that field has a special meaning in this database.
In order to make it more obvious for end users, I also want to title it with something along the lines of “(select if none)”.

I’m currently doing this, but it only inserts the ‘blank’ item when creating a new object, not when editing one.

# _child_form.html.erb

<%= simple_form_for @child do |f| %>
  <%= f.input :first_name %>
  <%= f.input :last_name %>
  <%= f.association :parent, :collection => @parents, :prompt => "(select if none)" %>

  <%= f.button.submit %>
<% end %>

.

# child_controller.rb

def new
  @child = Child.new
  @parents = Parent.all
end

def edit
  @child = Child.find(params[:id])
  @parents = Parent.all
end

Answer 1

You want to use :include_blank, not :prompt

<%= f.association :parent, :collection => @parents, :include_blank => "(select if none)" %>

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