ios 获取选定的索引标签栏控制器 Swift
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Get selected index tabbar controller Swift
提问by Maystro
I'm trying to get the selected index of the tabbarController.
我正在尝试获取 tabbarController 的选定索引。
let application = UIApplication.sharedApplication().delegate as AppDelegate
let tabbarController = application.tabBarController as UITabBarController
let selectedIndex = tabBarController.selectedIndex
I'm getting this error: 'UITabBarController?' does not have a member named 'selectedIndex'
我收到此错误： 'UITabBarController?' does not have a member named 'selectedIndex'
Am I missing something?
我错过了什么吗？
回答by return true
application.tabBarControlleris an optional, this means it can be nil.
If you are sure it will never be nil, do this:
application.tabBarController是可选的，这意味着它可以是nil. 如果您确定它永远不会nil，请执行以下操作：
var selectedIndex = tabBarController!.selectedIndex
回答by nabu
you should try this:
你应该试试这个：
let application = UIApplication.shared.delegate as! AppDelegate
let tabbarController = application.window?.rootViewController as! UITabBarController
let selectedIndex = tabbarController.selectedIndex
