best way of using UserControl.xaml in GroupBox or other container

See more:

C#

WPF

Hello everybody

I'm Novice in wpf and I'm try to use a ListBox whith elements in left hand and have a container in right hand to show custom UserControl, when I click an Item form ListBox to show related UserControl in right hand.

Is there a good way to do this?
I try to use windows Resource and then add this resource to group box with this code:

<pre lang="xml"><Window.Resources>
        <Border x:Key="FileProperties">
            <StackPanel>
                <StackPanel Orientation="Horizontal">
                    <RadioButton Margin="5" GroupName="File">File Name</RadioButton>
                    <TextBox x:Name="txtFilePath" Text="{Binding Value}" Width="180" Margin="5"/>
                    <Button x:Name="btnBrowse" Margin="5" Template="{DynamicResource GlassButton}" Click="btnBrowse_Click">Browse</Button>
                </StackPanel>
                <StackPanel Orientation="Horizontal">
                    <RadioButton Margin="5" GroupName="File">Select Variable</RadioButton>
                    <ComboBox Margin="5"></ComboBox>
                </StackPanel>
            </StackPanel>
        </Border>

</Windows.Resource>

GroupBoxProperties.Content = this.TryFindResource("the Resource name");

But I have problem too,
My problem was that I can't access elements in Resource, thus I try to use UserControl Instead of Resource.

Is there good way to do it?