dynamic loading of order articles in balancing "add article"

[wvengen]

In the balancing screen, the "add article" button brings up a select box containing all articles from the supplier. This can take a very long time. It would be much nicer to do this using ajax.

The dropdown-select2 branch would be a good starting point, as well as

• http://rails-select2-example.herokuapp.com/
• http://gistflow.com/posts/428-autocomplete-with-rails-and-select2
• http://stackoverflow.com/questions/16464128/select2-ajaxd-to-a-model-configuration

[wvengen]

done in dropdown-select2 branch, which has been merged into master