AcManager.Controls.Helpers.FancyBackgroundManager.ChangeBackground C# (CSharp) Метод

        public void ChangeBackground([CanBeNull] string filename) {
            if (filename == null) return;
            _queue.Enqueue(filename);

            if (_timer != null) return;
            _timer = new DispatcherTimer(DispatcherPriority.Background) {
                Interval = TimeSpan.FromSeconds(1),
                IsEnabled = true
            };
            _timer.Tick += Timer_Tick;
        }