CodeMirror

Add

gem 'codemirror-rails'

to your Gemfile.

RailsAdmin.config do |config|
  config.model Team do
    edit do
      # For RailsAdmin >= 0.5.0
      field :description, :code_mirror
      # For RailsAdmin < 0.5.0
      # field :description do
      #   codemirror true
      # end
    end
  end
end

This code that you see upper hide all other columns and left only description. Ruby 2.1.0 Rails 4.0.2 - this configuration helped me.

RailsAdmin.config do |config|
  config.model Team do
    configure :code, :code_mirror
  end
end

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