NSUbiquitousKeyValueStore.Notifications.ObserveDidChangeExternally Method

Definition

Namespace:

Foundation

Assembly:

Xamarin.iOS.dll

Overloads

ObserveDidChangeExternally(EventHandler<NSUbiquitousKeyValueStoreChangeEventArgs>)	Strongly typed notification for the DidChangeExternallyNotification constant.
ObserveDidChangeExternally(NSObject, EventHandler<NSUbiquitousKeyValueStoreChangeEventArgs>)	Strongly typed notification for the DidChangeExternallyNotification constant.

ObserveDidChangeExternally(EventHandler<NSUbiquitousKeyValueStoreChangeEventArgs>)

Strongly typed notification for the DidChangeExternallyNotification constant.

public static Foundation.NSObject ObserveDidChangeExternally (EventHandler<Foundation.NSUbiquitousKeyValueStoreChangeEventArgs> handler);

static member ObserveDidChangeExternally : EventHandler<Foundation.NSUbiquitousKeyValueStoreChangeEventArgs> -> Foundation.NSObject

Parameters

handler

EventHandler<NSUbiquitousKeyValueStoreChangeEventArgs>

Method to invoke when the notification is posted.

Returns

NSObject

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 developers can use this method in their code:

//
// Lambda style
//

// listening
notification = NSUbiquitousKeyValueStore.Notifications.ObserveDidChangeExternally ((sender, args) => {
    /* Access strongly typed args */
    Console.WriteLine ("Notification: {0}", args.Notification);

    Console.WriteLine ("ChangedKeys", args.ChangedKeys);
    Console.WriteLine ("ChangeReason", args.ChangeReason);
});

// To stop listening:
notification.Dispose ();

//
//Method style
//
NSObject notification;
void Callback (object sender, Foundation.NSUbiquitousKeyValueStoreChangeEventArgs args)
{
    // Access strongly typed args
    Console.WriteLine ("Notification: {0}", args.Notification);

    Console.WriteLine ("ChangedKeys", args.ChangedKeys);
    Console.WriteLine ("ChangeReason", args.ChangeReason);
}

void Setup ()
{
    notification = NSUbiquitousKeyValueStore.Notifications.ObserveDidChangeExternally (Callback);
}

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

ObserveDidChangeExternally(NSObject, EventHandler<NSUbiquitousKeyValueStoreChangeEventArgs>)

Strongly typed notification for the DidChangeExternallyNotification constant.

public static Foundation.NSObject ObserveDidChangeExternally (Foundation.NSObject objectToObserve, EventHandler<Foundation.NSUbiquitousKeyValueStoreChangeEventArgs> handler);

static member ObserveDidChangeExternally : Foundation.NSObject * EventHandler<Foundation.NSUbiquitousKeyValueStoreChangeEventArgs> -> Foundation.NSObject

Parameters

objectToObserve

NSObject

The object to observe.

handler

EventHandler<NSUbiquitousKeyValueStoreChangeEventArgs>

Method to invoke when the notification is posted.

Returns

NSObject

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 DidChangeExternallyNotification notifications.

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

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

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