Binding a Converter to background border in order to alternate background listviewitem

Question

Hi!

I want to alternate the background of the listviewitems by binding a converter to the background border of each listview item.

listview.xaml:

<l:cBackgroundConvertor x:Key="myConverter"/>

<Style x:Key="{x:Type ListViewItem}" TargetType="ListViewItem">
    <Setter Property="SnapsToDevicePixels" Value="true"/>
    <Setter Property="Height" Value="45"/>
    <Setter Property="OverridesDefaultStyle" Value="true"/>

    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="{x:Type ListViewItem}">

                <Border Name="Border" Padding="2" SnapsToDevicePixels="true">
                    <Border.Background>
                            <SolidColorBrush Color="{Binding RelativeSource={RelativeSource Self}, Converter={StaticResource myConverter}}" />                         
                    </Border.Background>
                     <GridViewRowPresenter VerticalAlignment="{TemplateBinding VerticalContentAlignment}"/>                      
                </Border>

                <ControlTemplate.Triggers>
                    <Trigger Property="IsSelected" Value="true">
                        <Setter Property="Foreground" Value="DarkBlue"/>
                        <Setter TargetName="Border" Property="Background" Value="{StaticResource DarkYellowBrush}"/>
                    </Trigger>
                    <Trigger Property="IsMouseOver" Value="true">
                        <Setter Property="Foreground" Value="DarkBlue"/>
                        <Setter TargetName="Border" Property="Background" Value="{StaticResource MouseOverBrush}"/>
                    </Trigger>
                </ControlTemplate.Triggers>
            </ControlTemplate>
        </Setter.Value>
    </Setter>

</Style>

<...>

my converter class:

namespace GesHoras.Classes { public sealed class cBackgroundConvertor : IValueConverter { public object Convert(object value, Type targetType, object parameter, CultureInfo culture) { ListViewItem item = (ListViewItem)value; ListView listView = ItemsControl.ItemsControlFromItemContainer(item) as ListView;

            // Get the index of a ListViewItem
            int index = listView.ItemContainerGenerator.IndexFromContainer(item);

            if (index % 2 == 0)
            {
                return Brushes.LightBlue;                    
            }
            else
            {
                return Brushes.Beige;
            }
        }

        public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
        {
            throw new NotSupportedException();
        }

}

}

---

I get an error message in runtime (it's in Spanish sorry, it says it cannot convert 'System.Windows.Media.SolidColorBrush' in 'System.Windows.Controls.ListViewItem':

El código de usuario no controló System.InvalidCastException Message="No se puede convertir un objeto de tipo 'System.Windows.Media.SolidColorBrush' al tipo 'System.Windows.Controls.ListViewItem'." Source="GesHoras" StackTrace: en GesHoras.Classes.cBackgroundConvertor.Convert(Object value, Type targetType, Object parameter, CultureInfo culture) en E:\Proyectos\VS2008\Mañas\GesHorasApp\Classes\cBackgroundConvertor.cs:línea 17 en System.Windows.Data.BindingExpression.TransferValue(Object newValue, Boolean isASubPropertyChange) en System.Windows.Data.BindingExpression.Activate(Object item) en System.Windows.Data.BindingExpression.AttachToContext(AttachAttempt attempt) en System.Windows.Data.BindingExpression.AttachOverride(DependencyObject target, DependencyProperty dp) en System.Windows.Data.BindingExpressionBase.Attach(DependencyObject target, DependencyProperty dp) en System.Windows.Data.BindingExpressionBase.OnAttach(DependencyObject d, DependencyProperty dp) en System.Windows.DependencyObject.SetValueCommon(DependencyProperty dp, Object value, PropertyMetadata metadata, Boolean coerceWithDeferredReference, OperationType operationType, Boolean isInternal) en System.Windows.DependencyObject.SetValue(DependencyProperty dp, Object value) en System.Windows.TemplateApplicationHelper.SetDependencyValueCore(DependencyObject dependencyObject, DependencyProperty dp, Object value) en System.Windows.Markup.BamlRecordReader.SetDependencyValue(DependencyObject dependencyObject, DependencyProperty dependencyProperty, Object value) en System.Windows.Markup.BamlRecordReader.SetDependencyComplexProperty(Object currentTarget, BamlAttributeInfoRecord attribInfo, Object o) InnerException:

I know there are other maners to alternate background for listview items but they don't work when grouping.

Thanks in advance!