public OptionWindowViewModel(IOptionSources optionSource)
 {
     System.Diagnostics.Debug.WriteLine($"[{DateTime.Now}] Create OptionWindowViewModel");
     _optionSource         = optionSource;
     FontSize              = _optionSource.FontSize;
     FontSizeMagnification = _optionSource.FontSizeMagnification;
 }
 public MainWindowViewModel(IOptionSources optionSource)
 {
     System.Diagnostics.Debug.WriteLine($"[{DateTime.Now}] Create MainWindowViewModel");
     _optionSource = optionSource;
     PropertyChangedEventManager.AddListener(_optionSource, this, nameof(IOptionSources.FontSize));
     PropertyChangedEventManager.AddListener(_optionSource, this, nameof(IOptionSources.FontSizeMagnification));
     FontSize = _optionSource.FontSize;
 }