In the meantime to get around the thread problem I emailed about, I though I would add an NSMenuItem to the menu so that the user can click an 'Update Now' button and update the data on demand. However, whenever any of my menuitems are clicked I get the same error: /Users/karl/projects/gigameter/GigaMeter/build/Debug/GigaMeter.app/Contents/Resources/rb_main.rb:22:in `NSApplicationMain': wrong number of arguments (0 for 1) (ArgumentError) from /Users/karl/projects/gigameter/GigaMeter/build/Debug/GigaMeter.app/Contents/Resources/rb_main.rb:22:in `<main>' This is how my 'Update Now' menu items is declared (here *target* is a reference to the Controller instance): self.updateNow = self.menu.addItemWithTitle_action_keyEquivalent_('Update Now', 'actionUpdateNow', 'u') self.updateNow.enabled = true self.updateNow.target = target self.updateNow.toolTip = 'Update your Usage Data' and my Controller class has: class Controller attr_accessor :actionQuit, :actionConfigure, :actionUpdateNow def actionUpdateNow(sender) puts "action update called\n" doLogin saveDataToDisk self.menu.update(self.user) end ... end The menu is added to an NSStatusBar as so: menuZone = NSMenu.menuZone self.menu = NSMenu.allocWithZone(menuZone).init self.statusBar = NSStatusBar.systemStatusBar.statusItemWithLength(NSVariableStatusItemLength) self.statusBar.menu = self.menu Any ideas what's going on here? -- Karl Varga kjvarga@gmail.com Cell: +61 (0)4 2075 1356