Binding custom Dependency Property to ListView width not updating - wpf

Question

I have an IValueConverter named CategoryToGridViewConverter which has a DependencyProperty named ListViewWidthProperty. I have also inherited my converter from DependencyObject so that it will work with DependencyProperties. Here is how my converter is defined:
internal class CategoryToGridViewConverter : DependencyObject, IValueConverter
{
public static readonly DependencyProperty ListViewWidthProperty = DependencyProperty.Register("ListViewWidth", typeof (double),
typeof (CategoryToGridViewConverter), new PropertyMetadata(0d, PropertyChangedCallback));
private static void PropertyChangedCallback(DependencyObject dependencyObject, DependencyPropertyChangedEventArgs dependencyPropertyChangedEventArgs)
{
Debug.WriteLine("ListViewWidth: " + dependencyPropertyChangedEventArgs.NewValue);
}
public double ListViewWidth {
get { return (double)GetValue(ListViewWidthProperty); }
set { SetValue(ListViewWidthProperty, value); }
}
public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
{
//Not relevant
}
public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
{
//Not relevant
}
}
}
Pretty simple. Then I am creating this converter in XAML (In ListView Resources section) like this:
<ListView Grid.Row="0" BorderThickness="0"
ItemsSource="{Binding SelectedCategory.Entries}"
x:Name="listView"
SizeChanged="ListView_OnSizeChanged">
<ListView.Resources>
<local:CategoryToGridViewConverter x:Key="CategoryToGridViewConverter" ListViewWidth="{Binding listView, Path=Width, Mode=OneWay}"/>
</ListView.Resources>
<ListView.View>
<Binding Path="SelectedCategory" Converter="{StaticResource CategoryToGridViewConverter}"/>
</ListView.View>
</ListView>
But the problem is that ListViewWidth never updates. It always stays at 0. But the ListView in question is obviously not having 0 width.
What am I doing wrong?
Edit: It also gives a binding error on output screen:
System.Windows.Data Error: 2 : Cannot find governing FrameworkElement
or FrameworkContentElement for target element.
BindingExpression:Path=Width; DataItem=null; target element is
'CategoryToGridViewConverter' (HashCode=33594544); target property is
'ListViewWidth' (type 'Double')
Does DependencyProperties only work for FrameworkElements? If so, how will my converter get to know about ListView's width?

Answer 1

I think you can just use a multi-value converter.
<local:CategoryToGridViewMultiConverter x:Key="CategoryToGridViewConverter" />
The converter:
public class CategoryToGridViewMultiConverter: IMultiValueConverter
{
public object Convert(object[] values, Type targetType, object parameter, CultureInfo culture)
{
var category = (Category)values[0]; // Assumption: you're using a class named Category
var listViewWidth = (double)values[1];
// same logic you had before
}
public object[] ConvertBack(object value, Type[] targetTypes, object parameter, CultureInfo culture)
{
throw new NotImplementedException();
}
}
Usage:
<ListView.View>
<MultiBinding Converter="{StaticResource CategoryToGridViewConverter}">
<Binding Path="SelectedCategory" />
<Binding ElementName="listView" Path="Width" Mode="OneWay" />
</MultiBinding>
</ListView.View>