private void TransmitToViewDataIsTransmit_PropertyChanged(object sender, System.ComponentModel.PropertyChangedEventArgs e) { if ((e.PropertyName == "IsTransmit") && (sender is TransmitToViewData viewData) && (TransmitToItems.Contains(viewData))) { if (viewData.IsTransmit) { if (TransmitToSelectedChannels == null) { TransmitToSelectedChannels = viewData.Transmit; } else { TransmitToSelectedChannels += viewData.Transmit; } } else { try { TransmitToSelectedChannels -= viewData.Transmit; } catch { } } } }