How to hide a control if the underlying DataContext is null?

This approach is easier:

<CheckBox Visibility="{Binding Path=checkedField, TargetNullValue=Collapsed }">

When the bound property checkedField is null, the Visibility will be set to Collapsed.

Have a converter like follows,

public sealed class NullToVisibilityConverter : IValueConverter{    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)    {        return value == null ? Visibility.Hidden: Visibility.Visible;    }    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)    {        throw new NotImplementedException();    }}

Now, bind the property with the Visibility property as well. Like,

<ListBox ItemsSource="{Binding Path=Squad}"          Visibility="{Binding Converter={StaticResource nullToVisibilityConverter},                               Path=Squad}">    <ListBox.ItemTemplate>        <DataTemplate>            <CheckBox Content="{Binding}" />        </DataTemplate>    </ListBox.ItemTemplate></ListBox>

I also needed this for a WindowsPhone WinRT app. I ended up using @PrinceAshitaka's converter with a minor modification in the binding as suggested in this answer to a similar question

You should use FallbackValue=Collapsed to avoid showing the control precisely when the datacontext is null. Not sure why TargetNullValue=Collapsed didn't work for me.

Visibility="{Binding Converter={StaticResource NullToVisibilityConverter}, FallbackValue=Collapsed}"