text: Q:
  
  Custom button in ActiveAdmin
  
  On ActiveAdmin, I have a form like this:
  Note that "My thingy" is not on the DB, but calculated with the data from an API.
  
  I want to add a filter for this field. What I'd like is to send this abc text as a parameter to the same edit action in which I am.
  
  My form looks like this:
  form do |f|
    f.inputs "Details" do
      f.input :my_thingy,
        label: 'My thingy',
        as: :select,
        collection: my_thingys,
      f.input :my_thingy_filter, label: "Filter My thingy by..."
      f.button :filter
    end
    f.actions
  end
  
  What I'd like is for this button to redirect to the same page, with the value of my_thingy_filter as a parameter.
  How can I do that?
  
  A:
  
  I solved this using a member_action: 
  member_action :thingy_filter, method: :patch do
    redirect_to edit_thingy_path(resource, thingy_filter: params["thingy"]["thingy_filter"])
  end
  
  And formaction with the button:
  form do |f|
    f.inputs "Details" do
      f.input :my_thingy,
        label: 'My thingy',
        as: :select,
        collection: my_thingys,
      f.input :my_thingy_filter, label: "Filter My thingy by..."
      f.button "Filter", formaction: "thingy_filter"
    end
    f.actions
  end
  
  Anyhow, this problem was better solved by adding a better select
  
  