Activeadmin extension: Cascade selection _ror

Activeadmin extension: Cascade selection

1. Create a new Common.js file in Active_admin.js's sibling directory,
And then join in the active_admin.js.
= Require common
(If the new file and Active_admin.js are not in the same sibling directory, the file path after require should be modified accordingly)


2, Common.js the relevant code is as follows:


The article_title here is automatically generated for form forms, in the form "[Model]_[field]", which is modified according to the actual situation.

    $ (function () {
      $ (' #article_title '). Change (function () {
        $.ajax ({
          URL: '/admin/articles/get_secondary_ Subject_by_subject ',
          type: ' POST ',
          data: {
            subject_id: $ (this). val ()
          },
          dataType: ' JSON ',
          Headers: {
            ' X-csrf-token ': $ (' meta[name= ' csrf-token '] '). attr (' content ')
          },
          success:function (data) {
            $ (' #article_content '). HTML ("");
            var str = ';
            for (var i = 0; i < data.length ++i) {
              str = ' <option value= ' + data[i].id + ' "> ' + data[i].name + ' </ Option> ';
            };
            $ (' #article_content '). Append (str);
          },
          error:function () {

          }
        });
      }
    );

3, the RB file related code is as follows:

   Collection_action:get_secondary_subject_by_subject,: Method =>:p ost do
     @subject_id = params[:subject_id]
     @secondary_subjects = Subject.where ("parent_subject_id =?", @subject_id)
     Render:json => @secondary_ Subjects.to_json (: Only => [: ID,: name]) ' and return '

   Controller do
     def new
       @article = article.new< c8/> @subjects = Subject.order ("id ASC"). Where ("parent_subject_id is null")
       @secondary_subjects = Subject.order (" ID ASC "). WHERE (" parent_subject_id =? ", @subjects. First.id)
     end

     def edit
       @subjects = Subject.order (" id ASC "). Where (" parent_subject_id is null ")
       @secondary_subjects = Subject.order (" id ASC "). WHERE (" parent_subject_ id =? ", @subjects. First.id)
     end

   f.input:title,: As =>: SELECT,: Collection => subjects,: inclu  De_blank => false
   f.input:content: As =>: SELECT,: Collection => secondary_subjects,: Include_blank => False

The above content is sorted by Bruce.xue.