MFMessageComposeViewController.Notifications.ObserveTextMessageAvailabilityDidChange Method
Definition
Important
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Overloads
| ObserveTextMessageAvailabilityDidChange(EventHandler<MFMessageAvailabilityChangedEventArgs>) |
Strongly typed notification for the TextMessageAvailabilityDidChangeNotification constant. |
| ObserveTextMessageAvailabilityDidChange(NSObject, EventHandler<MFMessageAvailabilityChangedEventArgs>) |
Strongly typed notification for the TextMessageAvailabilityDidChangeNotification constant. |
ObserveTextMessageAvailabilityDidChange(EventHandler<MFMessageAvailabilityChangedEventArgs>)
Strongly typed notification for the TextMessageAvailabilityDidChangeNotification constant.
public static Foundation.NSObject ObserveTextMessageAvailabilityDidChange (EventHandler<MessageUI.MFMessageAvailabilityChangedEventArgs> handler);static member ObserveTextMessageAvailabilityDidChange : EventHandler<MessageUI.MFMessageAvailabilityChangedEventArgs> -> Foundation.NSObjectParameters
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 developers can use this method in their code:
//
// Lambda style
//
// listening
notification = MFMessageComposeViewController.Notifications.ObserveTextMessageAvailabilityDidChange ((sender, args) => {
/* Access strongly typed args */
Console.WriteLine ("Notification: {0}", args.Notification);
Console.WriteLine ("TextMessageAvailability", args.TextMessageAvailability);
});
// To stop listening:
notification.Dispose ();
//
//Method style
//
NSObject notification;
void Callback (object sender, MessageUI.MFMessageAvailabilityChangedEventArgs args)
{
// Access strongly typed args
Console.WriteLine ("Notification: {0}", args.Notification);
Console.WriteLine ("TextMessageAvailability", args.TextMessageAvailability);
}
void Setup ()
{
notification = MFMessageComposeViewController.Notifications.ObserveTextMessageAvailabilityDidChange (Callback);
}
void Teardown ()
{
notification.Dispose ();
}
Applies to
ObserveTextMessageAvailabilityDidChange(NSObject, EventHandler<MFMessageAvailabilityChangedEventArgs>)
Strongly typed notification for the TextMessageAvailabilityDidChangeNotification constant.
public static Foundation.NSObject ObserveTextMessageAvailabilityDidChange (Foundation.NSObject objectToObserve, EventHandler<MessageUI.MFMessageAvailabilityChangedEventArgs> handler);static member ObserveTextMessageAvailabilityDidChange : Foundation.NSObject * EventHandler<MessageUI.MFMessageAvailabilityChangedEventArgs> -> Foundation.NSObjectParameters
- objectToObserve
- NSObject
The object to observe.
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 TextMessageAvailabilityDidChangeNotification notifications.
// Listen to all notifications posted for any object
var token = MFMessageComposeViewController.Notifications.ObserveTextMessageAvailabilityDidChange ((notification) => {
Console.WriteLine ("Observed TextMessageAvailabilityDidChangeNotification!");
};
// Listen to all notifications posted for a single object
var token = MFMessageComposeViewController.Notifications.ObserveTextMessageAvailabilityDidChange (objectToObserve, (notification) => {
Console.WriteLine ($"Observed TextMessageAvailabilityDidChangeNotification for {nameof (objectToObserve)}!");
};
// Stop listening for notifications
token.Dispose ();