Gui improvements, ordering

app/models/element.rb

@@ -8,6 +8,8 @@ class Element < ApplicationRecord
 
   delegate :report, to: :page
 
+  after_validation :set_position
+
   # Calculate actual conformity level:
   # - if a success_criterion has result :failed -> the confirmity_level
   #   of that success_criterion is not reached.
@@ -30,4 +32,9 @@ class Element < ApplicationRecord
   def max_level
     @max_level ||= success_criteria.reject(&:not_applicable?).max(&:level)
   end
+
+  def set_position
+    Rails.logger.debug("element: position #{position}")
+    self.position ||= (page.elements.pluck(:position).max || 0) + 1
+  end
 end