WPF和MVVM：在运行时更改数据绑定转换器

I am using WPF and the MVVM pattern in my user interface. In my ViewModel I have a List containing distances in millimetres, which I display in a ListView by binding ListView.ItemsSource to the List. However, I would like the values displayed to use a more natural unit - either metres or feet depending on the state of a "metric" checkbox.I am using WPF and the MVVM pattern in my user