IOS的MVC和MVVM模式简明介绍

1  let center = NSNotificationCenter.defaultCenter()
2         
3         center.addObserverForName(UIContentSizeCategoryDidChangeNotification,
4             object: UIApplication.sharedApplication(),
5             queue: NSOperationQueue.mainQueue())
6             { notification in
7                 let c = notification.userInfo?[UIContentSizeCategoryNewValueKey]
8         }

1   webView.addObserver(self, forKeyPath: "estimatedProgress", options: .New, context: nil)
2 
3      override func observeValueForKeyPath(keyPath: String?, ofObject object: AnyObject?, change: [NSObject : AnyObject]?, context: UnsafeMutablePointer<Void>) {
4              if (keyPath == "estimatedProgress") {
5                  progressView.hidden = webView.estimatedProgress == 1
6                  progressView.setProgress(Float(webView.estimatedProgress), animated: true)
7              }
8          }