How do I hide the header in a WPF Expander?

Question

I have a business requirement that when the user clicks a series of checkboxes in a WPF application that it will show panels depending upon what checkboxes they select. I would like to use the expander panel but I am not sure how to hide the header. The user should not be allowed to see it unless they check the checkbox. Does anyone know?

Answer 1

You can do this via making a custom Style for your Expander.

However, it might be easier to just place the controls in a different panel, and set it's visibility to Collapsed in response to the check box state. The main reason to use Expander is specifically to have the header and controls.

Answer 2

While not the ideal approach you could go this route...

    <Expander>
        <Expander.Header>
            <TextBlock Visibility="{Binding IsExpanded, RelativeSource={RelativeSource AncestorType={x:Type Expander}, Mode=FindAncestor}, 
                 Converter={StaticResource BoolToVisibilityConverter}}">My Expander</TextBlock>
        </Expander.Header>
    </Expander>

...where BoolToVisibilityConverter is something like...

    public class BoolToVisibilityConverter : IValueConverter
    {
        #region IValueConverter Members

        public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
            if ((bool)value)
                return Visibility.Visible;
            return Visibility.Collapsed;
        }

        public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
            if ((Visibility)value == Visibility.Visible)
                return true;
            return false;
        }

        #endregion
    }