UIApplication.Notifications.ObserveDidEnterBackground UIApplication.Notifications.ObserveDidEnterBackground Method

Definition

Overloads

ObserveDidEnterBackground(EventHandler<NSNotificationEventArgs>) ObserveDidEnterBackground(EventHandler<NSNotificationEventArgs>)

Strongly typed notification for the DidEnterBackgroundNotification constant.

ObserveDidEnterBackground(NSObject, EventHandler<NSNotificationEventArgs>) ObserveDidEnterBackground(NSObject, EventHandler<NSNotificationEventArgs>)

Strongly typed notification for the DidEnterBackgroundNotification constant.

ObserveDidEnterBackground(EventHandler<NSNotificationEventArgs>) ObserveDidEnterBackground(EventHandler<NSNotificationEventArgs>)

Strongly typed notification for the DidEnterBackgroundNotification constant.

public static Foundation.NSObject ObserveDidEnterBackground (EventHandler<Foundation.NSNotificationEventArgs> handler);
static member ObserveDidEnterBackground : EventHandler<Foundation.NSNotificationEventArgs> -> Foundation.NSObject

Parameters

handler
EventHandler<NSNotificationEventArgs>

Method to invoke when the notification is posted.

Returns

Token object that can be used to stop receiving notifications by either disposing it or passing it to RemoveObservers(IEnumerable<NSObject>)

Remarks

The following example shows how you can use this method in your code


//
// Lambda style
//

// listening notification = UIApplication.Notifications.ObserveDidEnterBackground ((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 = UIApplication.Notifications.ObserveDidEnterBackground (Callback); }

void Teardown () { notification.Dispose (); }

ObserveDidEnterBackground(NSObject, EventHandler<NSNotificationEventArgs>) ObserveDidEnterBackground(NSObject, EventHandler<NSNotificationEventArgs>)

Strongly typed notification for the DidEnterBackgroundNotification constant.

public static Foundation.NSObject ObserveDidEnterBackground (Foundation.NSObject objectToObserve, EventHandler<Foundation.NSNotificationEventArgs> handler);
static member ObserveDidEnterBackground : Foundation.NSObject * EventHandler<Foundation.NSNotificationEventArgs> -> Foundation.NSObject

Parameters

objectToObserve
NSObject NSObject

The object to observe.

handler
EventHandler<NSNotificationEventArgs>

Method to invoke when the notification is posted.

Returns

Token object that can be used to stop receiving notifications by either disposing it or passing it to RemoveObservers(IEnumerable<NSObject>)

Remarks

This method can be used to subscribe for DidEnterBackgroundNotification notifications.


// Listen to all notifications posted for any object
var token = UIApplication.Notifications.ObserveDidEnterBackground ((notification) => {
	Console.WriteLine ("Observed DidEnterBackgroundNotification!");
};

// Listen to all notifications posted for a single object var token = UIApplication.Notifications.ObserveDidEnterBackground (objectToObserve, (notification) => { Console.WriteLine ($"Observed DidEnterBackgroundNotification for {nameof (objectToObserve)}!"); };

// Stop listening for notifications token.Dispose ();

Applies to