public IDisposable Subscribe(IQuickCaptionObserver observer)
{
_logService.TraceEnter();
try
{
_logService.Trace("Checking if observer is already subscribed...");
if (_observers.Contains(observer))
{
return(new Unsubscriber <IQuickCaptionObserver>(_observers, observer));
}
_logService.Trace("Observer is not subscribed. Subscribing...");
_observers.Add(observer);
_logService.Trace("Notifying observer of current state...");
var captions = GetQuickCaptions();
Notify(observer, captions);
return(new Unsubscriber <IQuickCaptionObserver>(_observers, observer));
}
finally
{
_logService.TraceExit();
}
}
private void Notify(IQuickCaptionObserver observer, IList <string> captions)
{
_logService.TraceEnter();
try
{
_logService.Trace("Clearing current list...");
observer.OnClear();
_logService.Trace($"Notifying of {captions.Count} captions...");
foreach (var caption in captions)
{
_logService.Trace($@"Notifying of ""{caption}""...");
observer.OnNext(caption);
}
_logService.Trace("All captions have been returned...");
observer.OnCompleted();
}
catch (Exception ex)
{
observer.OnError(ex);
}
finally
{
_logService.TraceExit();
}
}
