Add a parameter to a WPF custom control based on ITypeEditor?

Question

C#, WPF, xceed PropertyGrid. I am using a custom control to provide a browse button in a PropertyGrid. There are variations in use case (e.g. most obviously browsing for a folder vs file), and creating separate editors for those cases would not be very DRY. Ideally I would like to introduce a parameter, but I am not sure how to pass that to the control. Is there a reasonably simple way to achieve this?

To me the most elegant solution would seem to be able to pass it an enum (for 'mode'), but if I could get the property that the editor is attached to (i.e. ProjectFolder in the following example) then that would also serve the purpose.

public partial class PropertyGridFilePicker : ITypeEditor
{
    string rtn = "";
    public PropertyGridFilePicker()
    {
        InitializeComponent();
    }

    public string Value
    {
        get { return (string)GetValue(ValueProperty); }
        set { SetValue(ValueProperty, value); }
    }

    // Using a DependencyProperty as the backing store for Value.  This enables animation, styling, binding, etc...
    public static readonly DependencyProperty ValueProperty =
        DependencyProperty.Register("Value", typeof(string), typeof(PropertyGridFilePicker), new PropertyMetadata(null));

    public FrameworkElement ResolveEditor(PropertyItem propertyItem)
    {
        Binding binding = new Binding("Value");
        binding.Source = propertyItem;
        binding.Mode = propertyItem.IsReadOnly ? BindingMode.OneWay : BindingMode.TwoWay;
        BindingOperations.SetBinding(this, ValueProperty, binding);
        return this;
    }

    private void PickFileButton_Click(object sender, RoutedEventArgs e)
    {
        OpenFileDialog fd = new OpenFileDialog();
        if (fd.ShowDialog() == true && fd.CheckFileExists)
        {
            Value = fd.FileName;
            Value = rtn;
        }
    }
}

It is used like this:

[Editor(typeof(MyControls.PropertyGridFilePicker), typeof(MyControls.PropertyGridFilePicker))]
public string ProjectFolder { get; set; } = "";

Answer 1

Answer given here:

Possible to call the constructor of a WPF type editor (inheriting from ITypeEditor)?

Although posted as a different question, this related to the same problem. I asked for clarification on the Dependency Injection solution proposed in the other answer given here since I didn't understand how this could work. And it seems it wouldn't.