skulle vel funke denne?

gistfile1.cs

// View Model:
public class ValueViewModel : ViewModel
{
  private bool _checked;

  public bool Checked
  {
      get { return _checked; }
      set
      {
          _checked = value;
          NotifyPropertyChanged();
          NotifyPropertyChanged("StatusColor");
      }
  }

  public Color StatusColor
  {
      get { return Checked ? Color.Green : Color.Red; }
  }
}

// View:
public class ValueView : ContentView
{
    public ValueView()
    {
        var layout = new Label
        {
            XAlign = TextAlignment.Center,
            YAlign = TextAlignment.Center,
            Font = Font.BoldSystemFontOfSize(NamedSize.Medium),
        };
        layout.SetBinding(Label.TextProperty, "Name");
        layout.SetBinding(Label.BackgroundColorProperty, new Binding("StatusColor", BindingMode.TwoWay));
            
        Content = layout;
    }
}

// Setter BindingContext fra MainView