AVAsset.Notifications.ObserveDurationDidChange 方法
定義
重要
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多載
ObserveDurationDidChange(EventHandler<NSNotificationEventArgs>)
常數的 DurationDidChangeNotification 強型別通知。
public static Foundation.NSObject ObserveDurationDidChange (EventHandler<Foundation.NSNotificationEventArgs> handler);static member ObserveDurationDidChange : EventHandler<Foundation.NSNotificationEventArgs> -> Foundation.NSObject參數
- handler
- EventHandler<NSNotificationEventArgs>
在發生通知時回應通知的處理常式。
傳回
權杖物件，可用來停止接收通知，方法是處置通知或傳遞至 RemoveObservers(IEnumerable<NSObject>)
備註
這個方法可以用來訂閱 DurationDidChangeNotification 通知。
// Listen to all notifications posted for any object
var token = AVAsset.Notifications.ObserveDurationDidChange ((notification) => {
Console.WriteLine ("Observed DurationDidChangeNotification!");
};
// Listen to all notifications posted for a single object
var token = AVAsset.Notifications.ObserveDurationDidChange (objectToObserve, (notification) => {
Console.WriteLine ($"Observed DurationDidChangeNotification for {nameof (objectToObserve)}!");
};
// Stop listening for notifications
token.Dispose ();
適用於
ObserveDurationDidChange(NSObject, EventHandler<NSNotificationEventArgs>)
常數的 DurationDidChangeNotification 強型別通知。
public static Foundation.NSObject ObserveDurationDidChange (Foundation.NSObject objectToObserve, EventHandler<Foundation.NSNotificationEventArgs> handler);static member ObserveDurationDidChange : Foundation.NSObject * EventHandler<Foundation.NSNotificationEventArgs> -> Foundation.NSObject參數
- objectToObserve
- NSObject
要觀察的特定物件。
- handler
- EventHandler<NSNotificationEventArgs>
在發生通知時回應通知的處理常式。
傳回
權杖物件，可用來停止接收通知，方法是處置通知或傳遞至 RemoveObservers(IEnumerable<NSObject>)
備註
這個方法可以用來訂閱 DurationDidChangeNotification 通知。
// Listen to all notifications posted for any object
var token = AVAsset.Notifications.ObserveDurationDidChange ((notification) => {
Console.WriteLine ("Observed DurationDidChangeNotification!");
};
// Listen to all notifications posted for a single object
var token = AVAsset.Notifications.ObserveDurationDidChange (objectToObserve, (notification) => {
Console.WriteLine ($"Observed DurationDidChangeNotification for {nameof (objectToObserve)}!");
};
// Stop listening for notifications
token.Dispose ();