ios - 使用 UINavigationController 时将 View Controller 转换到 MasterViewController

Question

我正在创建一个简单的“解决方案”应用程序，但在将当前 View Controller 转换为 MasterViewControllet 时我遇到了一个问题 - 我想这样做是为了设置它的一些变量。 我收到的错误是“无法将‘UINavigationController’类型的值 (0x10c534670) 转换为‘Resolution_App.MasterViewController’ (0x10ac97d00)。” 这是我的主要 Storyboard: 这是我的“添加新分辨率” View Controller 中的代码 请就如何正确转换有什么建议吗？

class EditViewController: UIViewController {
@IBOutlet weak var resolutionTitle: UITextField!
@IBOutlet weak var achievedDate: UITextField!

override func viewDidLoad() {
    super.viewDidLoad()

    // Do any additional setup after loading the view.
}

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}

@IBAction func saveButton(sender: AnyObject) {
    var newResolution = ["name":resolutionTitle.text,"achievingDate":achievedDate.text,"startingDate":"\(NSDate())"] as Dictionary<String,String>

    var destinationController = presentingViewController as! MasterViewController
    destinationController.objects.insert(newResolution, atIndex: 0)
    destinationController.notifyTableViewForNewInsertion()
    destinationController.saveDateToFile()


    self.dismissViewControllerAnimated(true, completion: {})

}


// MARK: - Navigation

// In a storyboard-based application, you will often want to do a little preparation before navigation
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
    // Get the new view controller using segue.destinationViewController.
    // Pass the selected object to the new view controller.

}


}

Answer 1

呈现模态 EditViewController 的 View Controller 是包含 MasterViewController 而不是 MasterViewController 本身的 UINavigationController。您应该创建一个协议(protocol)和一个委托(delegate)来在 EditViewController 和 MasterViewController 之间传递数据。您可以找到有关协议(protocol)的更多信息 here .

或者说:

var destinationController = presentingViewController.viewControllers[0] as! MasterViewController