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public class Registration { public void SendUpdate() { var info = new RegistrationInfo { // ...һЩÊôÐÔ }; Messenger.Default.Send(info); } }
public class RegisteredUser
{
public RegisteredUser()
{
Messenger.Default.Register<RegistrationInfo>(
this, HandleRegistrationInfo);
}
private void HandleRegistrationInfo(RegistrationInfo
info)
{
// ¸üÐÂÒÑ×¢²áµÄÓû§ÐÅÏ¢
}
}
public class RegistrationInfo
{
// ...һЩÊôÐÔ
} |
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public UserControl() { InitializeComponent(); // ʹÓÃÃüÃû·½·¨½øÐÐ×¢²á ---- Loaded += Figure2ControlLoaded;
Messenger.Default.Register<AnyMessage>(
this, HandleAnyMessage);
// ʹÓÃÄäÃû Lambda ½øÐÐ×¢²á ----
Loaded += (s, e) => { // Ö´ÐÐij²Ù×÷ };
Messenger.Default.Register<AnyMessage>(
this, message => { // Ö´ÐÐij²Ù×÷ });
}
private void HandleAnyMessage(AnyMessage message)
{
// Ö´ÐÐij²Ù×÷
}
private void Figure2ControlLoaded (object sender,
RoutedEventArgs e)
{
// Ö´ÐÐij²Ù×÷
} |
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public void RunOnBackgroundThread() { // Ö´ÐÐijºǫ́²Ù×÷ DispatcherHelper.CheckBeginInvokeOnUI( () => { Messenger.Default.Send(new ConfirmationMessage()); }); } |
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_first ÈÔÒýÓÃËü¡£À¬»ø»ØÊÕÆ÷ÒÀÀµÓÚͨ¹ý¼ÆËã¶Ô¶ÔÏóµÄÒýÓÃÀ´È·¶¨ÄÜ·ñ½«Ëü´ÓÄÚ´æÖÐɾ³ý£¬µ« _second
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public class Setup { private First _first = new First(); private Second _second = new Second(); public void InitializeObjects() { _first.AddRelationTo(_second); }
public void Cleanup()
{
_second = null;
// ¼´Ê¹ _second ʵÀýÉèÖÃΪ¿Õ£¬ËüÒ²ÈԻᱣÁôÔÚÄÚ´æÖУ¬ÒòΪÒýÓüÆÊý²»ÎªÁ㣨_first
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}
}
public class First
{
private object _another;
public void AddRelationTo(object another)
{
_another = another;
}
}
public class Second { } |
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public class SuperSimpleMessenger { private readonly List<WeakReference> _receivers = new List<WeakReference>(); public void Register(IReceiver receiver) { _receivers.Add(new WeakReference(receiver)); }
public void Send(object message)
{
// Ëø¶¨½ÓÊÕ¶ËÒÔÃâ·¢Éú¶àÏß³ÌÎÊÌâ¡£
lock (_receivers)
{
var toRemove = new List<WeakReference>();
foreach (var reference in _receivers.ToList())
{
if (reference.IsAlive)
{
((IReceiver)reference.Target).Receive(message);
}
else
{
toRemove.Add(reference);
}
}
// ɾ³ýÎÞЧÒýÓá£ÔÚÆäËûÑ»·ÖÐÖ´Ðд˲Ù×÷£¬ÒÔÃâÔÚÐ޸ĵ±Ç°Ñ»··ÃÎʵļ¯ºÏʱ·¢ÉúÒì³£¡£
foreach (var dead in toRemove)
{
_receivers.Remove(dead);
}
}
}
} |
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public class FirstViewModel { public FirstViewModel() { Messenger.Default.Register<NotificationMessage>( this, message => { if (message.Sender is MainViewModel) { // ´ËÏûÏ¢ÊÇÒª·¢Ë͸øÎÒ¡£ } }); } }
public class SecondViewModel
{
public SecondViewModel()
{
Messenger.Default.Register<NotificationMessage>(
this, message =>
{
if (message.Sender is SettingsViewModel)
{
// ´ËÏûÏ¢ÊÇÒª·¢Ë͸øÎÒ
}
});
}
} |
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public class MainViewModel { private Messenger _privateMessenger; public MainViewModel() { _privateMessenger = new Messenger(); SimpleIoc.Default.Register(() => _privateMessenger, "PrivateMessenger"); }
public void Update()
{
_privateMessenger.Send(new NotificationMessage("DoSomething"));
}
}
public class FirstViewModel
{
public FirstViewModel()
{
var messenger = SimpleIoc.Default.GetInstance<Messenger>("PrivateMessenger");
messenger.Register<NotificationMessage>(
this, message =>
{
// ´ËÏûÏ¢ÊÇÒª·¢Ë͸øÎÒ¡£
});
}
} |
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public class MainViewModel { public static readonly Guid Token = Guid.NewGuid(); public void Update() { Messenger.Default.Send(new NotificationMessage("DoSomething"), Token); } }
public class FirstViewModel
{
public FirstViewModel()
{
Messenger.Default.Register<NotificationMessage>(
this, MainViewModel.Token, message =>
{
// ´ËÏûÏ¢ÊÇÒª·¢Ë͸øÎÒ¡£
});
}
} |
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public class Sender { public void SendBoolean() { Messenger.Default.Send(true); }
public void SendNotification()
{
Messenger.Default.Send( new NotificationMessage<bool>(true,
Notifications.PlayPause));
}
}
public class Receiver
{
public Receiver()
{
Messenger.Default.Register<bool>( this,
b => { // ²»È·¶¨ÈçºÎ´¦Àí´Ë²¼¶û¡£});
Messenger.Default.Register<NotificationMessage<bool>>(
this, message =>
{
if (message.Notification == Notifications.PlayPause)
{
// ¶ÔÏûÏ¢Ö´ÐÐij²Ù×÷¡£
Content.Debug.WriteLine(message.Notification +
":"+ message.Content);
}
});
}
} |
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Light Toolkit °üº¬¿É³öÓÚ´ËÄ¿µÄ½øÐÐÅÉÉúµÄ MessageBase À࣬µ«¾ø²»Ç¿ÖÆÒªÇó½«ËüÓÃÓÚ´úÂë¡£
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Observable-Object ºÍ ViewModelBase ÀàÌرðÓÐÓá£ÕâЩÀàÊÇ INotifyPropertyChanged
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·¢ËÍ PropertyChangedMessage
public class BankViewModel :ViewModelBase { public const string BalancePropertyName = "Balance"; private double _balance; public double Balance { get { return _balance; } set { if (Math.Abs(_balance - value) < 0.001) { return; } var oldValue = _balance; _balance = value; RaisePropertyChanged(BalancePropertyName, oldValue, value, true); } } }
public class Receiver
{
public Receiver()
{
Messenger.Default.Register<PropertyChangedMessage<double>>(
this, message =>
{
if (message.PropertyName == BankViewModel.BalancePropertyName)
{
Debug.WriteLine( message.OldValue + " -->
" + message.NewValue);
}
});
}
} |
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