protocol via script

data/modules/messagebox/messagebox.lua

@@ -1,11 +1,34 @@
-function autoDestroyParent()
-    self.parent:destroy()
+MessageBox = {}
+MessageBox.__index = MessageBox
+
+function MessageBox.create(title, text)
+    local msgBox = {}
+    setmetatable(msgBox, MessageBox)
+
+    local window = UI.load("messagebox.yml")
+    window.locked = true
+    window.title = title
+    window:child("textLabel").text = text
+    window:child("okButton").onClick = function()
+            self.parent:destroy()
+        end
+    window.onDestroy = function()
+            if msgBox.onDestroy then
+                msgBox.onDestroy()
+            end
+        end
+
+    msgBox.window = window
+    return msgBox
+end
+
+function MessageBox:destroy()
+    if self.window then
+        self.window:destroy()
+        self.window = nil
+    end
 end
 
 function messageBox(title, text)
-    local msgBox = UI.load("messagebox.yml")
-    msgBox.locked = true
-    msgBox.title = title
-    msgBox:child("textLabel").text = text
-    msgBox:child("okButton").onClick = autoDestroyParent
+    return MessageBox.create(title, text)
 end