You helped me write this c# code in wpf but our connection got broken and I don't know how to define AreAnyItemsSelected and SelectedItems, the last thing you said to me was this:

In the ControlTemplate, I added a TextBlock below the ToggleButton. The Text property is bound to the SelectedItems property of the parent CheckBoxComboBox using a converter. The Visibility property of the TextBlock is bound to the AreAnyItemsSelected property of the parent CheckBoxComboBox using a converter to show/hide the selected items text when there are selected items.

Make sure to define (CONNECTION BROKEN HERE)

<Grid>
    <Grid.Resources>
        <Style TargetType=“local:CheckBoxComboBox”>
            <Setter Property=“Background” Value=“White” />
            <Setter Property=“Template”>
                <Setter.Value>
                    <ControlTemplate TargetType=“local:CheckBoxComboBox”>
                        <Grid>
                            <Border Background=“{TemplateBinding Background}”
                                    BorderBrush=“{TemplateBinding BorderBrush}”
                                    BorderThickness=“{TemplateBinding BorderThickness}”>
                                <Grid>
                                    <ToggleButton x:Name=“ToggleButton”
                                              ContentTemplate=“{TemplateBinding SelectionBoxItemTemplate}”
                                              ContentTemplateSelector=“{TemplateBinding ItemTemplateSelector}”
                                              Focusable=“False”
                                              IsChecked=“{Binding IsDropDownOpen, Mode=TwoWay,
                                                                  RelativeSource={RelativeSource TemplatedParent}}”
                                              ClickMode=“Press”>

                                    <!-- … Rest of the template code … -->
                                    
                                    </ToggleButton>
                                    <TextBlock Text=“{Binding SelectedItems, RelativeSource={RelativeSource TemplatedParent}, Converter={StaticResource SelectedItemsConverter}}” 
                                               Margin=“3,0,0,0” 
                                               VerticalAlignment=“Center” 
                                               HorizontalAlignment=“Left” 
                                               Visibility=“{Binding AreAnyItemsSelected, RelativeSource={RelativeSource TemplatedParent}, Converter={StaticResource BooleanToVisibilityConverter}}”>
                                    </TextBlock>
                                </Grid>
                            </Border>
                            <Popup x:Name=“Popup”
                                   Placement=“Bottom”
                                   IsOpen=“{TemplateBinding IsDropDownOpen}”
                                   AllowsTransparency=“True”
                                   Focusable=“False”
                                   PopupAnimation=“Slide”>
                                <!-- … Rest of the template code … -->
                            </Popup>
                        </Grid>
                    </ControlTemplate>
                </Setter.Value>
            </Setter>
        </Style>
    </Grid.Resources>

    <!-- … Rest of the XAML code … -->
</Grid>