How do I edit a usercontrol's subcontrol template in xaml when adding the usercontrol to a window?

I have a user control that contains a listview. In the windows where I use this usercontrol, I want to be able to do something like what is shown below where I set the template for a control within the user control.

<ct:AutoCompleteComboBox 
            SelectedValue="{Binding Path=SelectedCountry}"
            ItemsSource="{Binding Path=CountryList}" >
        <ct:AutoCompleteComboBox.DropDownList >

            <ListView 
                Background="Blue"
                MinWidth="150" 
                MaxHeight="200">
                <ListView.View>
                    <GridView>
                        <GridView.Columns>
                            <GridViewColumn Header=" Name" DisplayMemberBinding="{Binding Name}"  >
                            </GridViewColumn>
                            <GridViewColumn Header="Desc" DisplayMemberBinding="{Binding Description}"  >
                            </GridViewColumn&开发者_StackOverflow社区gt;
                        </GridView.Columns>
                    </GridView>
                </ListView.View>
            </ListView>
        </ct:AutoCompleteComboBox.DropDownList>
    </ct:AutoCompleteComboBox>

How do I go about doing this? I found that if I made AutoCompleteComboBox.DropDownList a dependency property, then the code would compile. However, this DropDownList property is not actually added to my control (it is added to the parent container of ct:AutoCompleteComboBox).

Any idea of the proper way to do this?

Thanks in advance

Bind subcontrol's property you want to be available outside to the property you created in the container control.