У меня есть уведомление, которое возвращает словарь, как и в objective-c, но я не получаю ожидаемых результатов.
Вот метод, который публикует уведомление. Он фактически возвращает результаты (дату) выбора даты.
@IBAction func dateOfBirthAction(sender: AnyObject) {
println("Date: \(dateOfBirthPicker.date)")
var selectedDateDictionary = [dateOfBirthPicker.date, "dateOfBirth"]
NSNotificationCenter.defaultCenter().postNotificationName("dateOfBirth", object: nil, userInfo: [NSObject():selectedDateDictionary])
}
Вот наблюдатель уведомлений:
override func viewDidLoad() {
super.viewDidLoad()
NSNotificationCenter.defaultCenter().addObserver(self, selector: "dateOfBirth:", name: "dateOfBirth", object: nil)
}
func dateOfBirth(notification: NSNotification) {
println("userInfo: \(notification.userInfo)")
let returnedDateOfBirth = notification.userInfo!["dateOfBirth"] as NSString
println("returnedDateOfBirth: \(returnedDateOfBirth)")
playerInformationDateOfBirthLabel.text = returnedDateOfBirth
}
Я получаю следующую ошибку в строке let returnedDateOfBirth:String = notification.userInfo["dateOfBirth"]
userInfo: Optional([<NSObject: 0x7fb15a44a880>: <_TtCSs23_ContiguousArrayStorage00007FB15A4D4380 0x7fb15a4206a0>(
2014-09-18 12:07:07 +0000,
dateOfBirth
)
])
fatal error: unexpectedly found nil while unwrapping an Optional value
ПОЛНОЕ РЕШЕНИЕ
@IBAction func dateOfBirthAction(sender: AnyObject) {
var selectedDateDictionary = ["birthDate" : dateOfBirthPicker.date]
NSNotificationCenter.defaultCenter().postNotificationName("foundABirthDate", object: nil, userInfo:selectedDateDictionary)
}
override func viewDidLoad() {
super.viewDidLoad()
NSNotificationCenter.defaultCenter().addObserver(self, selector: "dateOfBirth:", name: "foundABirthDate", object: nil)
}
func dateOfBirth(notification: NSNotification) {
let playerBirthDate = notification.userInfo!["birthDate"] as NSDate
var dateFormatter: NSDateFormatter = NSDateFormatter()
//Specifies a long style, typically with full text, such as "November 23, 1937".
dateFormatter.dateStyle = NSDateFormatterStyle.LongStyle
let dateConvertedToString: String = dateFormatter.stringFromDate(playerBirthDate)
playerInformationDateOfBirthLabel.text = dateConvertedToString
}