Wrap namespace settings in a DynamicSetting class that can be subtyped to encapsulate behavior.

Author: varyonic

lib/active_admin/dynamic_setting.rb

@@ -0,0 +1,17 @@
+module ActiveAdmin
+
+  class DynamicSetting
+    def self.build(setting)
+      new(setting)
+    end
+
+    def initialize(setting)
+      @setting = setting
+    end
+
+    def value(*_args)
+      @setting
+    end
+  end
+
+end

lib/active_admin/dynamic_settings_node.rb

@@ -0,0 +1,28 @@
+require 'active_admin/dynamic_setting'
+require 'active_admin/settings_node'
+
+module ActiveAdmin
+
+  class DynamicSettingsNode < SettingsNode
+    class << self
+      def register(name, value)
+        class_attribute "#{name}_setting"
+        add_reader(name)
+        add_writer(name)
+        send "#{name}=", value
+      end
+
+      def add_reader(name)
+        define_singleton_method(name) do
+          send("#{name}_setting").value
+        end
+      end
+
+      def add_writer(name)
+        define_singleton_method("#{name}=") do |value|
+          send("#{name}_setting=", DynamicSetting.build(value))
+        end
+      end
+    end
+  end
+end

lib/active_admin/namespace_settings.rb

@@ -1,7 +1,7 @@
-require 'active_admin/settings_node'
+require 'active_admin/dynamic_settings_node'
 
 module ActiveAdmin
-  class NamespaceSettings < SettingsNode
+  class NamespaceSettings < DynamicSettingsNode
     # The default number of resources to display on index pages
     register :default_per_page, 30
 

lib/active_admin/settings_node.rb

@@ -6,7 +6,7 @@ class << self
       private_class_method :new
 
       # @returns anonymous class with same accessors as the superclass.
-      def build(superclass = SettingsNode)
+      def build(superclass = self)
         Class.new(superclass)
       end