title: Databind radiobutton group to property
body: <p>I have a radiobutton group:</p>
  
  <pre><code>&lt;TextBlock Height="24" Text="Update Interval (min):"/&gt;
  &lt;RadioButton x:Name="radioButtonTimerNone" IsChecked="{Binding UpdateInterval, Converter={StaticResource updateIntervalToCheckedConverter}, Mode=TwoWay}"} Content="None" /&gt;
  &lt;RadioButton x:Name="radioButtonTimerOne" IsChecked="{Binding UpdateInterval, Converter={StaticResource updateIntervalToCheckedConverter}, Mode=TwoWay}" 
                  Content="1" /&gt;
  &lt;RadioButton x:Name="radioButtonTimerFive" IsChecked="{Binding UpdateInterval, Converter={StaticResource updateIntervalToCheckedConverter}, Mode=TwoWay}" 
                  Content="5" /&gt;
  </code></pre>
  
  <p>And a property:</p>
  
  <pre><code>    public int UpdateInterval {
          get { return _updateInterval; }
          set { _updateInterval = value;
              onPropertyChanged("UpdateInterval");
          }
      }
  </code></pre>
  
  <p>How do I bind the radiobuttons to the property, so radioButtonTimerNone is checked when UpdateInterval is 0, radioButtonTimerOne is checked when UpdateInterval is 1, etc.<br>
  I have tried to create a converter, but it doesn't identify which rb is being set:  </p>
  
  <pre><code>[ValueConversion(typeof(RadioButton), typeof(bool))] 
  class UpdateIntervalToCheckedConverter : System.Windows.Data.IValueConverter
  public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
  </code></pre>
  
  <p>I expected 'value' to be a radiobutton, but it appears to be the value of UpdateInterval.</p>
  
  <p>Thanks for any hints...  </p>