/// <summary>
/// Subscribes supplied object to property changed notifications and invokes the provided callback
/// </summary>
/// <typeparam name="T">Type of subject</typeparam>
/// <param name="vmb">Subject</param>
/// <param name="path">Property path</param>
/// <param name="callback">Notification callback</param>
public static void NotifyOn <T>(this T vmb, string path, Action <object, object> callback)
{
Dictionary <string, NotificationHelperDp> block;
if (!_notifiers.TryGetValue(vmb, out block))
{
_notifiers.Add(vmb, block = new Dictionary <string, NotificationHelperDp>());
}
block.Remove(path);
NotificationHelperDp binder = new NotificationHelperDp(callback);
BindingOperations.SetBinding(binder, NotificationHelperDp.BindValueProperty,
#if NET || NETCORE || NETFRAMEWORK
new Binding(path)
{
Source = vmb
});
#else
new Binding {
Source = vmb, Path = new PropertyPath(path)
});
#endif
block.Add(path, binder);
}
private static void OnBindValueChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
NotificationHelperDp that = (NotificationHelperDp)d;
if (!that._isDetached && that._callback != null
#if NET || NETCORE || NETFRAMEWORK
&& BindingOperations.IsDataBound(that, BindValueProperty)
#endif
)
{
that._callback(e.NewValue, e.OldValue);
}
}