AVAsset.Notifications.ObserveMediaSelectionGroupsDidChange 方法
定义
重要
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重载
ObserveMediaSelectionGroupsDidChange(EventHandler<NSNotificationEventArgs>)
常量的强类型通知 MediaSelectionGroupsDidChangeNotification 。
public static Foundation.NSObject ObserveMediaSelectionGroupsDidChange (EventHandler<Foundation.NSNotificationEventArgs> handler);static member ObserveMediaSelectionGroupsDidChange : EventHandler<Foundation.NSNotificationEventArgs> -> Foundation.NSObject参数
- handler
- EventHandler<NSNotificationEventArgs>
发生通知时响应通知的处理程序。
返回
令牌对象，可用于通过释放通知或将其传递给来停止接收通知 RemoveObservers(IEnumerable<NSObject>)
注解
此方法可用于订阅 MediaSelectionGroupsDidChangeNotification 通知。
// Listen to all notifications posted for any object
var token = AVAsset.Notifications.ObserveMediaSelectionGroupsDidChange ((notification) => {
Console.WriteLine ("Observed MediaSelectionGroupsDidChangeNotification!");
};
// Listen to all notifications posted for a single object
var token = AVAsset.Notifications.ObserveMediaSelectionGroupsDidChange (objectToObserve, (notification) => {
Console.WriteLine ($"Observed MediaSelectionGroupsDidChangeNotification for {nameof (objectToObserve)}!");
};
// Stop listening for notifications
token.Dispose ();
适用于
ObserveMediaSelectionGroupsDidChange(NSObject, EventHandler<NSNotificationEventArgs>)
常量的强类型通知 MediaSelectionGroupsDidChangeNotification 。
public static Foundation.NSObject ObserveMediaSelectionGroupsDidChange (Foundation.NSObject objectToObserve, EventHandler<Foundation.NSNotificationEventArgs> handler);static member ObserveMediaSelectionGroupsDidChange : Foundation.NSObject * EventHandler<Foundation.NSNotificationEventArgs> -> Foundation.NSObject参数
- objectToObserve
- NSObject
要观察的特定对象。
- handler
- EventHandler<NSNotificationEventArgs>
发生通知时响应通知的处理程序。
返回
令牌对象，可用于通过释放通知或将其传递给来停止接收通知 RemoveObservers(IEnumerable<NSObject>)
注解
此方法可用于订阅 MediaSelectionGroupsDidChangeNotification 通知。
// Listen to all notifications posted for any object
var token = AVAsset.Notifications.ObserveMediaSelectionGroupsDidChange ((notification) => {
Console.WriteLine ("Observed MediaSelectionGroupsDidChangeNotification!");
};
// Listen to all notifications posted for a single object
var token = AVAsset.Notifications.ObserveMediaSelectionGroupsDidChange (objectToObserve, (notification) => {
Console.WriteLine ($"Observed MediaSelectionGroupsDidChangeNotification for {nameof (objectToObserve)}!");
};
// Stop listening for notifications
token.Dispose ();