wpf RadioButton控件的一个bug，onpropertychanged后会修改旧属性的值

测试代码下载：http://files.cnblogs.com/djangochina/RadioButtonBug.zip

从上面列表选择不同的行，再设置下面不同的radiobutton看看结果

 

bug情况简单描述如下

一个列表控件listbox、listview或者datagrid，绑定如下

SelectedItem="{Binding SelectedData}"

当然这个SelectedData是一个实现了INotifyPropertyChanged的实体。比如说是Person,里面有 IsMan和IsWoman两个bool

绑定到两个RadionButton

<RadioButton IsChecked="{Binding IsMan}" Content="Man"/>

                                        <RadioButton IsChecked="{Binding IsWoman}" Content="Woman"/>

当来回切换列表控件的选中项的时候会发现这两个RadioButton的值会有错误，会修改旧选中项属性的值。

解决方法

    public class RadioButtonExtended : RadioButton

    {

        public static readonly DependencyProperty IsCheckedExtProperty =

            DependencyProperty.Register("IsCheckedExt", typeof(bool?), typeof(RadioButtonExtended),

                                        new FrameworkPropertyMetadata(false, FrameworkPropertyMetadataOptions.Journal | FrameworkPropertyMetadataOptions.BindsTwoWayByDefault, IsCheckedRealChanged));



        private static bool _isChanging;



        public RadioButtonExtended()

        {

            Checked += RadioButtonExtendedChecked;

            Unchecked += RadioButtonExtendedUnchecked;

        }



        public bool? IsCheckedExt

        {

            get

            {

                return (bool?)GetValue(IsCheckedExtProperty);

            }

            set

            {

                SetValue(IsCheckedExtProperty, value);

            }

        }



        public static void IsCheckedRealChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)

        {

            _isChanging = true;

            ((RadioButtonExtended)d).IsChecked = (bool)e.NewValue;

            _isChanging = false;

        }



        private void RadioButtonExtendedChecked(object sender, RoutedEventArgs e)

        {

            if (!_isChanging)

                IsCheckedExt = true;

        }



        private void RadioButtonExtendedUnchecked(object sender, RoutedEventArgs e)

        {

            if (!_isChanging)

                IsCheckedExt = false;

        }

    }

 

使用

<controls:RadioButtonExtended GroupName="Sex" IsCheckedExt="{Binding IsMan}" Content="Man"/>

<controls:RadioButtonExtended GroupName="Sex" IsCheckedExt="{Binding IsWoman}" Content="Woman"/>