/// <summary>
/// Adds a weak event listener for a PropertyChanged event.
/// </summary>
/// <param name="source">The source of the event.</param>
/// <param name="handler">The event handler.</param>
/// <exception cref="ArgumentNullException">source must not be <c>null</c>.</exception>
/// <exception cref="ArgumentNullException">handler must not be <c>null</c>.</exception>
protected void AddWeakEventListener(INotifyPropertyChanged source, PropertyChangedEventHandler handler)
{
if (source == null)
{
throw new ArgumentNullException("source");
}
if (handler == null)
{
throw new ArgumentNullException("handler");
}
PropertyChangedEventListener listener = propertyChangedListeners.LastOrDefault((l) => l.Source == source && l.Handler == handler);
if (listener == null)
{
listener = new PropertyChangedEventListener(source, handler);
}
else
{
return;
}
propertyChangedListeners.Add(listener);
PropertyChangedEventManager.AddListener(source, listener, string.Empty);
}
/// <summary>
/// Removes the weak event listener for a PropertyChanged event.
/// </summary>
/// <param name="source">The source of the event.</param>
/// <param name="handler">The event handler.</param>
/// <exception cref="ArgumentNullException">source must not be <c>null</c>.</exception>
/// <exception cref="ArgumentNullException">handler must not be <c>null</c>.</exception>
protected void RemoveWeakEventListener(INotifyPropertyChanged source, PropertyChangedEventHandler handler)
{
if (source == null)
{
throw new ArgumentNullException("source");
}
if (handler == null)
{
throw new ArgumentNullException("handler");
}
PropertyChangedEventListener listener = propertyChangedListeners.LastOrDefault((l) => l.Source == source && l.Handler == handler);
if (listener != null)
{
propertyChangedListeners.Remove(listener);
PropertyChangedEventManager.RemoveListener(source, listener, string.Empty);
}
}
/// <summary>
/// Adds a weak event listener for a PropertyChanged event.
/// </summary>
/// <param name="source">The source of the event.</param>
/// <param name="handler">The event handler.</param>
/// <exception cref="ArgumentNullException">source must not be <c>null</c>.</exception>
/// <exception cref="ArgumentNullException">handler must not be <c>null</c>.</exception>
protected void AddWeakEventListener( INotifyPropertyChanged source, PropertyChangedEventHandler handler )
{
if ( source == null )
throw new ArgumentNullException( "source" );
if ( handler == null )
throw new ArgumentNullException( "handler" );
PropertyChangedEventListener listener = propertyChangedListeners.LastOrDefault( ( l ) => l.Source == source && l.Handler == handler );
if ( listener == null )
listener = new PropertyChangedEventListener( source, handler );
else
return;
propertyChangedListeners.Add( listener );
PropertyChangedEventManager.AddListener( source, listener, string.Empty );
}
