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How to change the order of nested forms being rendered (especially blank forms)

Martin Straub
October 12, 2011Software engineer at makandra GmbH

Generally for nested forms, a blank form is placed below all other existing object forms. If you would like to change the position of the blank form(s) you can reorder the object's one-to-many association. For example you can put the blank form on top with the following snippet:

actors = movie.actors
actors.build
actors.unshift(actors.pop(1)) # won't work with Rails 4+
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Because build_for_form creates new objects and appends them to the one-to-many association collection object you only have to reorder the collection objects.

Sorting with Rails 3+

= form.fields_for :children, @parent.children.sort_by(&:name) do |fieldsform|
  …
Posted by Martin Straub to makandra dev (2011-10-12 09:27)