new useful function, cycleEvent

modules/client_topmenu/topmenu.otui

@@ -80,9 +80,6 @@ TopPanel
     margin-top: 8
     margin-right: 5
     @onSetup: |
-      local updateFunc
-      updateFunc = function()
+      cycleEvent(function()
         rootWidget:recursiveGetChildById('frameCounter'):setText('FPS: ' .. g_app.getBackgroundPaneFps())
-        scheduleEvent(updateFunc, 250)
-      end
-      addEvent(updateFunc)
+      end, 250)

modules/core_lib/globals.lua

@@ -41,6 +41,13 @@ function addEvent(callback, front)
   return event
 end
 
+function cycleEvent(callback, front)
+  local event = g_eventDispatcher.cycleEvent(callback, front)
+  -- must hold a reference to the callback, otherwise it would be collected
+  event._callback = callback
+  return event
+end
+
 
 function periodicalEvent(eventFunc, conditionFunc, delay, autoRepeatDelay)
   delay = delay or 30