swift - UiAlertView 或 UiAlertController 在 Swift 中只显示一次

Question

如何让我的 UiAlertController 或 UIAlertView 在 Swift 中只显示一次？

override func viewDidLoad() {

    var defaults: NSUserDefaults = NSUserDefaults.standardUserDefaults()

    if let nameIsNotNill = defaults.objectForKey("name") as? String {
        self.name.text = defaults.objectForKey("name") as String
    }

    if let phoneIsNotNill = defaults.objectForKey("phone") as? String {
        self.phone.text = defaults.objectForKey("phone") as String
    }

    var alert = UIAlertController(title: "Disclaimer", message: "WE STRIVES TO PROVIDE ACCURATE, UP-TO-DATE INFORMATION ON THIS APPS.", preferredStyle: UIAlertControllerStyle.Alert)

    alert.addAction(UIAlertAction(title: "Agree", style: UIAlertActionStyle.Default, handler: nil))
    alert.addAction(UIAlertAction(title: "Disagree", style: UIAlertActionStyle.Default, handler: nil))

    self.presentViewController(alert, animated: true, completion: nil)

    super.viewDidLoad()

}

Answer 1

在 import 命令下声明一个全局 Bool 变量:

var justOnce:Bool = true

你应该这样使用它:

override func viewDidLoad() {
    super.viewDidLoad()
    var defaults: NSUserDefaults = NSUserDefaults.standardUserDefaults()

    if let nameIsNotNill = defaults.objectForKey("name") as? String {
        name.text = defaults.objectForKey("name") as String
    }

    if let phoneIsNotNill = defaults.objectForKey("phone") as? String {
         phone.text = defaults.objectForKey("phone") as String
    }

    if justOnce {
       var alert = UIAlertController(title: "Disclaimer", message: "WE STRIVES TO PROVIDE ACCURATE, UP-TO-DATE INFORMATION ON THIS APPS.", preferredStyle: UIAlertControllerStyle.Alert)
       alert.addAction(UIAlertAction(title: "Agree", style: UIAlertActionStyle.Default, handler: nil))
alert.addAction(UIAlertAction(title: "Disagree", style: UIAlertActionStyle.Default, handler: nil))
       self.presentViewController(alert, animated: true, completion: nil)

        justOnce = false
    }
}