Binding to a sub-property

I built a struct named Fraction, with three properties: double Value, int Numerator and int Denominator. In my data source I use the Fraction as a property, Fraction Position.

The data is bound li开发者_Go百科ke this:

  <TextBox Text="{Binding Path=Position.Numerator}"/>
  <TextBox Text="{Binding Path=Position.Denominator}"/>

but the binding happens to work only one way - from source to target. I tried to catch the SourceUpdated event, but it didn't work.

Is there a way to force two-way binding? I tried Mode=TwoWay, but it didn't work either.

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You may have to create Position as a dependency property so that when target updates source updates too

Edit

please check it should be something like

public static readonly DependencyProperty PositionProperty = DependencyProperty.Register("Position", typeof(Fraction), typeof(NoteUserControl),new UIPropertyMetadata(new Fraction()));

public Fraction Position
        {
            get { return (Fraction)GetValue(PositionProperty ); }
            set 
            { 
                SetValue(PositionProperty, value); 

            }
        }

Hope NoteUserControl is the Class in which you have defined the dependency property