Set Grid Column Width to Bound Perctange

Question

I want to display a Rectangle with a dynamic Width based on a bound data source. I originally looked into using a Converter, but wasn't able to bind to the converter parameter to get a read dynamic width.

My most recent attempt was binding the parent column to the UtilPct property, which is a decimal in my BrokerCredit object. I think this is using the decimal value as an absolute instead of a percentage display.

How would I go about doing this? I'd like my Rectangle or the parent column to take up a percentage of the total column width according to the percentage in UtilPct. I'm still pretty new to WPF, so I appreciate any help! Thanks in advance.

XAML:

<ItemsControl x:Name="icBrokerCreditList" Grid.Row="1" Grid.Column="1" ItemsSource="{Binding Path=BrokerCreditList}" HorizontalAlignment="Stretch">
    <ItemsControl.ItemTemplate>
        <DataTemplate>
            <Grid HorizontalAlignment="Stretch">
                <Grid.RowDefinitions>
                    <RowDefinition Height="20"></RowDefinition>
                </Grid.RowDefinitions>
                <Grid.ColumnDefinitions>
                    <ColumnDefinition Width="150"></ColumnDefinition>
                    <ColumnDefinition x:Name="utilizationColumn" Width="{Binding Path=UtilPct}"></ColumnDefinition>
                </Grid.ColumnDefinitions>
                <TextBlock Grid.Row="0" Grid.Column="0" Background="White" Foreground="Black" FontSize="12" Text="{Binding Path=BrokerName}"></TextBlock>
                <Rectangle Width="auto" Fill="Green" Height="20" Grid.Row="0" Grid.Column="1">
                    <!--"{Binding Converter={StaticResource PercentageConverter}, 
                                        ElementName=utilizationColumn, Path=Width, ConverterParameter=.1}"-->                          
                </Rectangle>
            </Grid>
        </DataTemplate>
    </ItemsControl.ItemTemplate>
</ItemsControl>

Answer 1

You could use IMultiValue converter, this way you can pass in the Width and the Precentage so you can calculate the width of the column.

Example:

Converter:

public class PercentageConverter : IMultiValueConverter
{
    public object Convert(object[] values, Type targetType, object parameter, System.Globalization.CultureInfo culture)
    {
        if (values[0] is double && values[1] is double)
        {
            return (((double)values[0]) / 100) * ((double)values[1]);
        }
        return values[0];
    }

    public object[] ConvertBack(object value, Type[] targetTypes, object parameter, System.Globalization.CultureInfo culture)
    {
        throw new NotImplementedException();
    }
}

Xaml:

<Rectangle Width="auto" Fill="Green" Height="20" Grid.Row="0" Grid.Column="1">
    <Rectangle.Width>
        <MultiBinding Converter="{StaticResource PercentageConverter}">
            <Binding Path="Width" />
            <Binding Path="UtilPct" />
        </MultiBinding>
    </Rectangle.Width>
</Rectangle>