wpf customcontrol, how to bind button click inside itemscontrol DataTemplate

Question

I have custom control that inherit from Textbox, in .cs i have DependencyProperty SelectedItems (those items will show inside texbox if there is any) if not texbox looks like normal texbox.

In generic.xaml in Template i added new border and inside i put ItemsControl with item template like this

xaml itemControl part:

<Border BorderBrush="Green" BorderThickness="1">
                        <ItemsControl x:Name="PART_SelectedItemsHost"
                                ItemsSource="{TemplateBinding SelectedItems}"
                                ItemTemplate="{TemplateBinding SelectedItemsTemplate}"
                                VerticalAlignment="Stretch"
                                HorizontalAlignment="Stretch"                                                                      
                                Margin="{TemplateBinding Padding}"
                                Visibility="Visible">
                            <ItemsControl.ItemsPanel>
                                <ItemsPanelTemplate>
                                    <WrapPanel IsItemsHost="True">
                                    </WrapPanel>
                                </ItemsPanelTemplate>
                            </ItemsControl.ItemsPanel>                               
                        </ItemsControl>                            
                    </Border>

Xaml ItemTemplate part:

<DataTemplate x:Key="DefaultSelectedItemsTemplate" >
    <Border x:Name="selectedItemBorder" BorderBrush="Gray" BorderThickness="1" CornerRadius="5" Background="{DynamicResource {x:Static SystemColors.ControlBrushKey}}" Margin="5,1,1,1">
        <Grid>
            <Grid.ColumnDefinitions>
                <ColumnDefinition Width="*"/>
                <ColumnDefinition Width="15"/>
            </Grid.ColumnDefinitions>
            <TextBlock Grid.Column="0" Text="{Binding}" Margin="5,0,3,0"></TextBlock>
            <Button BorderThickness="0" Grid.Column="1" Click="???" or Command="???" >X</Button>
        </Grid>
    </Border>
</DataTemplate>

Now how can i bind that button "X" in my .cs file .. i am trying to do this overriding OnApplyTemplate() method ... and i did manage to bind mousedown when i click on item texbox but i dont know how to attach that click on button

my .cs part

            public override void OnApplyTemplate()
    {
        base.OnApplyTemplate();
        ItemsControl itmControl = GetTemplateChild("PART_SelectedItemsHost") as ItemsControl;

        if (itmControl != null)
        {
            itmControl.MouseLeftButtonDown += new MouseButtonEventHandler(itmControl_MouseLeftButtonDown);

            // blind click on X buttons in ItemsControl
        }

    }

    private void itmControl_MouseLeftButtonDown(object obj, MouseButtonEventArgs e)
    {
        //IsMouseLeftButtonDown = true;
        System.Diagnostics.Debug.WriteLine(e.OriginalSource.ToString());
        object item = (e.OriginalSource as FrameworkElement).DataContext;
        deleteSelectedItem(item);

    }

and here is picture how this control looks like ant that X button need to delete item from SelectedItem collection.

picture

Answer 1

The ItemsControl has the following name:

<ItemsControl x:Name="PART_SelectedItemsHost"

So in the template

<Button  BorderThickness="0" Grid.Column="1" Command="{Binding DataContext.DeleteItem, ElementName=PART_SelectedItemsHost}" CommandParameter="{Binding}">X</Button>