Binding IsChecked property of RadioButton in WPF

If you have tried to bind the RadioButton's IsChecked property in WPF to an object, you have most likely experienced the following problem: In OneWay bindings it works great. But if you have more than one RadioButtons binded TwoWay and you click on an unchecked one, you were expecting that the object to which the previously checked RadioButton was binded to receive the value of False. But you were wrong in your expectations. That's because for some reasons Microsoft does not obey bindings and does not pass the False value to the DependencyProperty and instead of that they just assign the value False directly to the property, which ruins the binding.

There are many proposed solutions to this around the internet, problem with all those is that they do not work with dynamically generated controls. So since I had to find a way to make this working with dynamic controls, decided to make a wrapper of the real RadioButton which will correctly Bind in two ways. Here is the code for the wrapper:

using System;
using System.IO;
using System.Printing;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Controls.Primitives;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Interop;
using System.Windows.Media;
using Microsoft.Win32;

namespace Controls
    public class RadioButtonExtended : RadioButton
        static bool m_bIsChanging = false;

        public RadioButtonExtended()
            this.Checked += new RoutedEventHandler(RadioButtonExtended_Checked);
            this.Unchecked += new RoutedEventHandler(RadioButtonExtended_Unchecked);

        void RadioButtonExtended_Unchecked(object sender, RoutedEventArgs e)
            if (!m_bIsChanging)
                this.IsCheckedReal = false;

        void RadioButtonExtended_Checked(object sender, RoutedEventArgs e)
            if (!m_bIsChanging)
                this.IsCheckedReal = true;

        public bool? IsCheckedReal
            get { return (bool?)GetValue(IsCheckedRealProperty); }
                SetValue(IsCheckedRealProperty, value);

        // Using a DependencyProperty as the backing store for IsCheckedReal. This enables animation, styling, binding, etc...
        public static readonly DependencyProperty IsCheckedRealProperty =
        DependencyProperty.Register("IsCheckedReal", typeof(bool?), typeof(RadioButtonExtended),
        new FrameworkPropertyMetadata(false, FrameworkPropertyMetadataOptions.Journal |

        public static void IsCheckedRealChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
            m_bIsChanging = true;
            ((RadioButtonExtended)d).IsChecked = (bool)e.NewValue;
            m_bIsChanging = false;

So now all you have to do is to use the ExtendedRadioButton instead of the built-in one and bind to the IsCheckedReal property instead of the IsChecked one.
Enjoy :)

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