void EnableVisibilityEvent(WindowFrameEvent ev)
{
if (!VisibilityEventsEnabled())
{
ContentView.AddObserver(this, HiddenProperty, NSKeyValueObservingOptions.New, IntPtr.Zero);
}
if (!eventsEnabled.HasFlag(ev))
{
eventsEnabled |= ev;
}
}
void IBackend.EnableEvent(object eventId)
{
if (eventId is WindowFrameEvent)
{
var @event = (WindowFrameEvent)eventId;
switch (@event)
{
case WindowFrameEvent.Hidden:
case WindowFrameEvent.Shown:
if (!VisibilityEventsEnabled())
{
ContentView.AddObserver(this, HiddenProperty, NSKeyValueObservingOptions.New, IntPtr.Zero);
}
break;
}
eventsEnabled |= @event;
}
}