Unable to access index of tabBar item using swift

问题:

Environment: xcode 6GM, Language Swift. I was setting image color of a tabBar item using this code in xcode 6 beta2

var cameraTab : UITabBarItem = self.tabBar.items[1] as UITabBarItem

But now in xcode 6GM it is giving error. Error: [AnyObject]? does not have a member named 'subscript'

回答1:

items is Optional - you can do:

   if let items = self.tabBar.items {
    println("\(items[1])")
  }

or

  var cameraTab : UITabBarItem = self.tabBar.items![1] as UITabBarItem

回答2:

items property is optional for tabBar. Try optional chaining:

var cameraTab : UITabBarItem = self.tabBar.items?[1] as UITabBarItem