void EnableVisibilityEvent(WindowFrameEvent ev) { if (!VisibilityEventsEnabled()) { ContentView.AddObserver(this, HiddenProperty, NSKeyValueObservingOptions.New, IntPtr.Zero); } if (!eventsEnabled.HasFlag(ev)) { eventsEnabled |= ev; } }
bool VisibilityEventsEnabled() { return(eventsEnabled.HasFlag(WindowFrameEvent.Hidden) || eventsEnabled.HasFlag(WindowFrameEvent.Shown)); }