Question

I am unable to get a custom binding working with a converter, getting this when building the project:

Error 2 Unknown property ‘Converter’ for type ‘MS.Internal.Markup.MarkupExtensionParser+UnknownMarkupExtension’ encountered while parsing a Markup Extension.

The error points to this code:

<KeyBinding 
        Key="{helper:KeyboardShortcut InsertTargetToSource, Converter={StaticResource KeyGestureConverterKey},ConverterParameter=Key}" 
        Modifiers="{helper:KeyboardShortcut InsertTargetToSource, Converter={StaticResource KeyGestureConverterKey},ConverterParameter=Modifiers}" 
        Command="{Binding CopyToTargetCommand}"/>

KeyboardShortCut is a binding from a Settings file :

public class KeyboardShortcutExtension : Binding
{
    public KeyboardShortcutExtension()
    {
        Initialize();
    }

    public KeyboardShortcutExtension(string path)
        : base(path)
    {
        Initialize();
    }

    private void Initialize()
    {
        this.Source = TI.Shortcuts.Default;
        this.Mode = BindingMode.TwoWay;
    }

}

And the converter converts from string (like “Ctrl+Shift+X”) to Key and Modifiers:

private KeyGestureConverter mConverter = new KeyGestureConverter();

    public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
    {
        var text = value.ToString();
        var gesture = mConverter.ConvertFromInvariantString(text) as KeyGesture;
        if (parameter == "Key")
        {
            return gesture.Key;
        }
        if (parameter == "Modifiers")
        {
            return gesture.Modifiers;
        }
        return gesture;
    }

Is there something I am missing? Or should I take a different approach when trying to bind from a string in Settings file to a KeyBinding?

EDIT:

Using the following code, everything works fine, but the code is not readable. Is there a way of generating this automatically, so in my markup I would write e.g. just

<MyKeyBinding Value="CopyToTargetCommand"/> 

and it would generate the rest?

<KeyBinding Command="{Binding CopyToTargetCommand}">
        <KeyBinding.Key>
            <helper:KeyboardShortcut Path="InsertTargetToSource" ConverterParameter="Key">
                <helper:KeyboardShortcut.Converter>
                    <StaticResource ResourceKey="KeyGestureConverterKey"/>
                </helper:KeyboardShortcut.Converter>
            </helper:KeyboardShortcut>
        </KeyBinding.Key>
        <KeyBinding.Modifiers>
            <helper:KeyboardShortcut Path="InsertTargetToSource" ConverterParameter="Modifiers">
                <helper:KeyboardShortcut.Converter>
                    <StaticResource ResourceKey="KeyGestureConverterKey"/>
                </helper:KeyboardShortcut.Converter>
            </helper:KeyboardShortcut>
        </KeyBinding.Modifiers>
    </KeyBinding>

Answer 1

class CustomizableKeyBinding : KeyBinding
{
    public CustomizableKeyBinding()
        : base()
    {
    }

    StringToKeyGestureConverter converter = new StringToKeyGestureConverter();

    public string Description
    {
        set
        {
            InitBindings(value);
        }
    }

    private void InitBindings(string value)
    {
        BindingOperations.SetBinding(this, KeyBinding.KeyProperty, new KeyboardShortcutExtension(value) { Converter = converter, ConverterParameter = "Key" });
        BindingOperations.SetBinding(this, KeyBinding.ModifiersProperty, new KeyboardShortcutExtension(value) { Converter = converter, ConverterParameter = "Modifiers" });
    }
}

Adn then in XAML:

 <helper:CustomizableKeyBinding Command="{Binding CopyToTargetCommand}" Description="..."/>