NSMetadataQuery.Notifications.ObserveGatheringProgress 方法
定義
重要
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多載
ObserveGatheringProgress(EventHandler<NSNotificationEventArgs>)
常數的 GatheringProgressNotification 強型別通知。
public static Foundation.NSObject ObserveGatheringProgress (EventHandler<Foundation.NSNotificationEventArgs> handler);
static member ObserveGatheringProgress : EventHandler<Foundation.NSNotificationEventArgs> -> Foundation.NSObject
參數
- handler
- EventHandler<NSNotificationEventArgs>
張貼通知時叫用的方法。
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
下列範例示範如何在程式碼中使用此方法
//
// Lambda style
//
// listening
notification = NSMetadataQuery.Notifications.ObserveGatheringProgress ((sender, args) => {
/* Access strongly typed args */
Console.WriteLine ("Notification: {0}", args.Notification);
});
// To stop listening:
notification.Dispose ();
//
//Method style
//
NSObject notification;
void Callback (object sender, Foundation.NSNotificationEventArgs args)
{
// Access strongly typed args
Console.WriteLine ("Notification: {0}", args.Notification);
}
void Setup ()
{
notification = NSMetadataQuery.Notifications.ObserveGatheringProgress (Callback);
}
void Teardown ()
{
notification.Dispose ();
}
適用於
ObserveGatheringProgress(NSObject, EventHandler<NSNotificationEventArgs>)
常數的 GatheringProgressNotification 強型別通知。
public static Foundation.NSObject ObserveGatheringProgress (Foundation.NSObject objectToObserve, EventHandler<Foundation.NSNotificationEventArgs> handler);
static member ObserveGatheringProgress : Foundation.NSObject * EventHandler<Foundation.NSNotificationEventArgs> -> Foundation.NSObject
參數
- objectToObserve
- NSObject
要觀察的物件。
- handler
- EventHandler<NSNotificationEventArgs>
張貼通知時叫用的方法。
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
這個方法可用來訂閱 GatheringProgressNotification 通知。
// Listen to all notifications posted for any object
var token = NSMetadataQuery.Notifications.ObserveGatheringProgress ((notification) => {
Console.WriteLine ("Observed GatheringProgressNotification!");
};
// Listen to all notifications posted for a single object
var token = NSMetadataQuery.Notifications.ObserveGatheringProgress (objectToObserve, (notification) => {
Console.WriteLine ($"Observed GatheringProgressNotification for {nameof (objectToObserve)}!");
};
// Stop listening for notifications
token.Dispose ();