Hi, I have a problem with binding in ComboBox. I'd like to bind ComboBox items to ListView columns and as a selected value return value of attached property defined on the selected column.

In example bellow you can see working sample that displays width of selected column. If you try to change SelectedValuePath in ComboBox into (loc:SampleBehavior.SampleValue) you get binding error:

BindingExpression path error: '(u:SearchableListView.SearchMemberPath)' property not found on 'object' ''GridViewColumn'

<Window x:Class="Problem_Sample1.Window1"
  xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
  xmlns:loc="clr-namespace:Problem_Sample1"
  WindowStartupLocation="CenterScreen"
  Title="Window1" 
  Height="300" Width="300">
  <DockPanel>
    <ComboBox DockPanel.Dock="Top"
         x:Name="combobox"
         ItemsSource="{Binding Path=View.Columns, ElementName=listview}"
         DisplayMemberPath="Header"
         SelectedValuePath="Width">
    </ComboBox>

    <StatusBar DockPanel.Dock="Bottom">
      <TextBlock>
        <TextBlock Text="Selected column (value): " />
        <TextBlock Text="{Binding Path=SelectedValue, ElementName=combobox}" />
      </TextBlock>
    </StatusBar>

    <ListView x:Name="listview">
      <ListView.View>
        <GridView>
          <GridViewColumn Header="Name" 
                  Width="101" 
                  loc:SampleBehavior.SampleValue="201" />
          <GridViewColumn Header="Surname" 
                  Width="102" 
                  loc:SampleBehavior.SampleValue="202" />
        </GridView>
      </ListView.View>
    </ListView>
  </DockPanel>
</Window>

SampleBehavior.cs

using System.Windows;
using System.Windows.Controls;

namespace Problem_Sample1
{
  public static class SampleBehavior
  {

    public static readonly DependencyProperty SampleValueProperty =
      DependencyProperty.RegisterAttached(
        "SampleValue",
        typeof (int),
        typeof (SampleBehavior));

    [AttachedPropertyBrowsableForType(typeof(GridViewColumn))]
    public static int GetSampleValue(GridViewColumn column)
    {
      return (int)column.GetValue(SampleValueProperty);
    }

    [AttachedPropertyBrowsableForType(typeof(GridViewColumn))]
    public static void SetSampleValue(GridViewColumn column, int value)
    {
      column.SetValue(SampleValueProperty, value);
    }

  }
}

Thanks for any help or suggestion.