I try to learn a little bit about how a listboxview combined with context menu works, so I've made the following XAML code:
<UserControl>
...
<ListView
x:Name="level1Lister"
Grid.Row="1"
behaviours:AutoScrollListViewBehaviour.ScrollOnNewItem="True"
ItemsSource="{Binding LogBuffer, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}">
<ListView.ItemContainerStyle>
<Style TargetType="ListViewItem">
<Setter Property="Padding" Value="1" />
<Setter Property="Margin" Value="2,0" />
<Setter Property="BorderThickness" Value="0" />
</Style>
</ListView.ItemContainerStyle>
<ListView.ItemsPanel>
<ItemsPanelTemplate>
<StackPanel Orientation="Vertical" />
</ItemsPanelTemplate>
</ListView.ItemsPanel>
<ListView.ItemTemplate>
<DataTemplate>
<StackPanel>
<StackPanel.ContextMenu>
<ContextMenu>
<MenuItem Command="{Binding Path=DataContext.ValidateAllCommand, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type ContextMenu}}, FallbackValue=9999999999}" Header="Copy" />
</ContextMenu>
</StackPanel.ContextMenu>
<TextBlock Foreground="{Binding Color, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" Text="{Binding Message, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" />
</StackPanel>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
</UserControl>
My main problem is that I'm not able to access my "ValidateAllCommand" function, for some reason... I think it has to do with the "RelativeSource={RelativeSource FindAncestor ... " part but I can't figure out how.
The "problem" with the ContextMenu is that it is not part of the visual tree. The reason is that the MenuItem uses a Popup to host the content. While the Popup itself is part of the visual tree, its Child content is disconnected as it is rendered in a new Window instance. We know there can can only be a single Window in the tree and this Window must be the root.
Since Binding.RelativeSource traverses the visual tree, starting within the detached tree of the Popup, to find the binding source, the Bindig does not resolve.
The Popup.Child content inherits the DataContext of the Popup. In case of the ContextMenu it means that the MenuItem inherits the DataContext from the ContextMenu or from the parent of the ContextMenu, to be more precise. In your scenario the DataContext is the data model of the ListBoxItem i.e. the DataContext of the DataTemplate.
This means, one solution could be to implement the command in the item model.
The second solution is to make use of routed commands. This solution might be more reasonable in your scenario. The routed command/event can cross the boundary between the two trees.
In the following example, I use the ApplicationCommands.Copy command, one of the predefined routed commands. The MenuItem.Parameter is bound to the DataContext, which is the item data model (inherited from the ContextMenu, as mentioned before). This way the command handler can know the data source.
The event handler can be attached to any parent element using the UIElement.CommandBindings property. In the example the handler is attached to the ListBox element:
MainWindow.xaml
<ListBox>
<ListBox.CommandBindings>
<CommandBinding Command="{x:Static ApplicationCommands.Copy}"
Executed="CopyCommand_Executed" />
</ListBox.CommandBindings>
<ListBox.ItemTemplate>
<DataTemplate DataType="{x:Type local:DataItem}">
<StackPanel>
<StackPanel.ContextMenu>
<ContextMenu>
<!--
Here we are in a detached visual tree.
The DataContext is inherited from the ContextMenu element.
The framework allows routed events to cross the boundaries between the trees.
-->
<MenuItem Command="{x:Static ApplicationCommands.Copy}"
CommandParameter="{Binding}"
Header="Copy" />
</ContextMenu>
</StackPanel.ContextMenu>
<TextBlock />
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
MainWindow.xaml.cs
private void CopyCommand_Executed(object sender, ExecutedRoutedEventArgs e)
{
var listBoxItemModel = e.Parameter as LogBufferItem;
// TODO::Handle Copy command. For example:
var commandTarget = this.DataContext as ICommandModel;
commandTarget.ValidateAllCommand.Execute(listBoxItemModel);
}
A third, but not recommended solution is to bind the DataContext of the ContextMenu parent to the context of interest:
<ListBox.ItemTemplate>
<DataTemplate DataType="{x:Type local:DataItem}">
<StackPanel>
<!-- DataTemplate DataContext -->
<Grid DataContext="{Binding RelativeSource={RelativeSource AncestorType=ListBox}, Path=DataContext}">
<!-- ListBox DataContext -->
<Grid.ContextMenu>
<ContextMenu>
<!--
Here we are in a detached visual tree.
The DataContext is inherited from the ContextMenu/Grid element.
-->
<MenuItem Command="{Binding ValidateAllCommand}"
Header="Copy" />
</ContextMenu>
</Grid.ContextMenu>
</Grid>
<!-- DataTemplate DataContext -->
<TextBlock />
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox
Related
There is a WPF MVVM app. On the main view I have a list of elements, which are defined with ListView.ItemTemplate, in that I want to have a context menu with Delete action.
The Command for that is separated from the view and is kept in ViewModel DreamListingViewModel.
The problem is that on clicking on Delete I can't get it to execute the command on ViewModelk as context there is that of the item, not the items container.
I can make it work somehow by moving the context menu definition outside of the list view elements, but then when I open the context menu, it flickers, as if it's being called "20" times (which what I think does happen, as many times as I have elements in collection), anyways, I need a clean solution for that and I am very bad with XAML.
Here is how my View looks:
<ListView.ItemTemplate>
<DataTemplate>
<Grid Margin="0 5 0 5" Background="Transparent" Width="auto">
<Grid.ContextMenu>
<ContextMenu>
<MenuItem Header="Delete"
Command="{Binding DeleteSelectedDream}"
CommandParameter="{Binding DeleteSelectedDream,
RelativeSource={RelativeSource
Mode=FindAncestor,
AncestorType={x:Type viewmodels:DreamListingViewModel}}}"
/>
</ContextMenu>
</Grid.ContextMenu>
...
It's the main window and initialized in a generic host in App.cs:
public partial class App : Application
{
private readonly IHost _host;
public App()
{
...
_host = Host.CreateDefaultBuilder().ConfigureServices(services =>
{
...
services.AddTransient<DreamListingViewModel>();
services.AddSingleton((s) => new DreamListingView()
{
DataContext = s.GetRequiredService<DreamListingViewModel>()
});
...
}).Build();
The Command and CommandParameter values are what I've been experimenting with, but it doesn't work
Here is how my ViewModel looks:
internal class DreamListingViewModel : ViewModelBase
{
public ICommand DeleteSelectedDream{ get; }
...
Finally, when the command is fired, I need to pass the current element on which the menu has been shown.
So, here is what I want:
User clicks on a list item with mouse right button - OK
Sees a menu with Delete entry - OK
On Delete click, Command DeleteSelectedDream is fired with current dream (item in the list) as a parameter - ERR
Your example is somewhat lacking necessary information, but I'll try to help.
First you need to verify that you are actually bound to your view model. Are you using Prism or just standard WPF ? In the constructor of your code-behind of your view, set up the DataContext to an instance of your VM.
InitializeComponent();
this.DataContext = new DreamListingViewModel();
Now, you bind to a relative source via Mode 'FindAncestor' and the AncestorType is set to the type of a view model. That usually won't work, as the view model is not naturally a part of the visual tree of your WPF view. Maybe your ItemTemplate somehow wires it up. In a large WPF app of mine I use Telerik UI for WPF and a similar approach to you, however, I set up the DataContext of the Context menu to a RelativeSource set to Self combined with Path set to PlacementTarget.DataContext.
You do not have to use all the XAML in my example, just observe how I do it. Exchange 'RadContextMenu' with 'ContextMenu', Ignore the Norwegian words - here and only use what you need :
<telerik:RadContextMenu x:Key="CanceledOperationsViewContextMenu" DataContext="{Binding RelativeSource={RelativeSource Mode=Self}, Path=PlacementTarget.DataContext, UpdateSourceTrigger=PropertyChanged}">
<MenuItem Header="{Binding PatientName}" IsEnabled="False" Style="{StaticResource ContextMenuHeading}" />
<MenuItem Header="Gå til aktuell SomeAcme-liste" IsEnabled="{Binding IsValid}" Command="{Binding NavigateToListCommand}" />
<MenuItem Header="Åpne protokoll..." Command="{Binding CommonFirstProtocolCommand, Mode=OneWay}" CommandParameter="{Binding}" />
<MenuItem Header="Åpne Opr.spl.rapport...." Command="{Binding CommonFirstNurseReportCommand, Mode=OneWay}" CommandParameter="{Binding}" />
</telerik:RadContextMenu>
In your example it will be :
<ContextMenu x:Key="SomeContextMenu" DataContext="{Binding RelativeSource={RelativeSource Mode=Self}, Path=PlacementTarget.DataContext, UpdateSourceTrigger=PropertyChanged}">
<MenuItem Header="Delete" />
Command="{Binding DeleteSelectedDream}"
CommandParameter="{Binding DeleteSelectedDream,
RelativeSource={RelativeSource
Mode=FindAncestor,
AncestorType={x:Type ListViewItem}}}"
/>
</telerik:RadContextMenu>
Now I here consider you are using the class ListViewItem
https://learn.microsoft.com/en-us/dotnet/api/system.windows.controls.listviewitem?view=netframework-4.8
It might be that you need to specify DataContext.DeleteSelectedDream here to be sure you bind up to the DataContext where your implementation of ICommand is.
Accidentally found this answer, that's basically what I needed, just added to it a CommandParameter to send the item and it works like magic!
<ListView Name="lvDreams" ItemsSource="{Binding Dreams}">
<ListView.ItemTemplate>
<DataTemplate>
<Grid Margin="0 5 0 5" Background="Transparent" Width="auto">
<Grid.ContextMenu>
<ContextMenu>
<MenuItem
Header="Delete"
Command="{Binding DataContext.DeleteSelectedDream, Source={x:Reference lvDreams}}"
CommandParameter="{Binding}"
/>
</ContextMenu>
</Grid.ContextMenu>
...
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
I find the following the simplest; perhaps it's because I do not understand WPF, but it's "simple" to remember, and it works with my MVVM pattern.
<ListBox ItemsSource="{Binding MyViewModelItemsCollection, Mode=OneWay}">
<ListBox.ItemTemplate>
<DataTemplate>
<Grid Background="Transparent" >
<TextBlock Text="{Binding Path=Name, Converter={StaticResource FullPathToFileName}, Mode=OneWay}" Grid.Column="0">
<TextBlock.ContextMenu>
<ContextMenu>
<MenuItem
Command="{Binding Path=DataContext.MyViewModelAction, RelativeSource={RelativeSource AncestorType=ListBox}}"
CommandParameter="{Binding}"
Header="{Binding Name, Converter={StaticResource resourceFormat}, ConverterParameter={x:Static res:Resources.CONTEXT_MENU_BLOCK_APPLICATION}}">
</MenuItem>
</ContextMenu>
</TextBlock.ContextMenu>
</TextBlock>
</grid>
</DataTemplate>
</ListBox.ItemTemplate
</ListBox>
The MyViewModelXXXXXXX named items are in the view model that is mapped to the data context of the control.
I want to show a contextMenu item when I am using rightclick on a treeview item.
After that, I want to use a command when I click on my MenuItem, but I need to bind the command with a different viewmodel and the command parameter with the good viewmodel who come from my treeview selected item.
So for the moment, I have something like that :
<TreeView x:Name="TreeViewProtocolsAndEquipments" AllowDrop="True"
ItemsSource="{Binding ModuleParams}">
<TreeView.Resources>
<!-- CONTEXT MENU -->
<!-- Protocol -->
<ContextMenu x:Key="ContextMenuProtocol">
<MenuItem Header="Add new equipment" Command="{Binding AddNewEquipmentCommand, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=UserControl}}" CommandParameter="{Binding RelativeSource={RelativeSource Self}}">
<MenuItem.Icon>
<Image Source="Images/Add.png" />
</MenuItem.Icon>
</MenuItem>
<Separator />
</ContextMenu>
<!-- MODULE XXX -->
<!-- ModuleParam > xxx -->
<HierarchicalDataTemplate DataType="{x:Type xxx:ModuleParamXXXViewModel}" ItemsSource="{Binding ModuleItems}">
<TextBlock Text="XXX" Foreground="Green" ContextMenu="{StaticResource ContextMenuProtocol}"/>
</HierarchicalDataTemplate>
</TreeView.Resources>
</TreeView>
For the moment my command is bind to xxx:ModuleParamXXXViewModel if I just let { binding }
Can I bind my Command to my ActivatedProtocolsAndEquipmentsTreeViewModel (the datacontext of this usercontrol) and keep on the CommandParameter my xxx:ModuleParamXXXViewModel (who is the Item from the treeview where we triggered the right click to show the contextMenu) ?
How can I achieve this in an other way with MVVM practice ?
I also tried to use this but it didn't work too :
<MenuItem Header="Add new equipment" Command="{Binding Path=DataContext.AddNewEquipmentCommand, Source={x:Reference TreeViewProtocolsAndEquipments}}" CommandParameter="{Binding RelativeSource={RelativeSource Self}}">
And with this i get Object Reference not set to an instance of an object
The UserControl is not a visual ancestor of the MenuItem since a ContextMenu resides in its own visual tree.
Bind the Tag property of the TextBlock to the UserControl and then bind the Command property to the PlacementTarget of the ContextMenu:
<TreeView x:Name="TreeViewProtocolsAndEquipments" AllowDrop="True"
ItemsSource="{Binding ModuleParams}">
<TreeView.Resources>
<!-- CONTEXT MENU -->
<!-- Protocol -->
<ContextMenu x:Key="ContextMenuProtocol">
<MenuItem Header="Add new equipment"
Command="{Binding PlacementTarget.Tag.DataContext.AddNewEquipmentCommand, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=ContextMenu}}"
CommandParameter="{Binding}">
<MenuItem.Icon>
<Image Source="Images/Add.png" />
</MenuItem.Icon>
</MenuItem>
<Separator />
</ContextMenu>
<!-- MODULE XXX -->
<!-- ModuleParam > xxx -->
<HierarchicalDataTemplate DataType="{x:Type xxx:ModuleParamXXXViewModel}" ItemsSource="{Binding ModuleItems}">
<TextBlock Text="XXX" Foreground="Green"
Tag="{Binding RelativeSource={RelativeSource AncestorType=UserControl}}"
ContextMenu="{StaticResource ContextMenuProtocol}"/>
</HierarchicalDataTemplate>
</TreeView.Resources>
</TreeView>
I am trying to bind DataGrid column header to its own ContextMenu like this:
<DataGrid x:Name="AllLogs">
<DataGrid.ContextMenu>
<ContextMenu>
<MenuItem Header="Show/Hide Columns"
ItemsSource="{Binding ElementName=AllLogs, Path=Columns}">
<MenuItem.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding Header}"></TextBlock>
</DataTemplate>
</MenuItem.ItemTemplate>
</MenuItem>
</ContextMenu>
</DataGrid.ContextMenu>
</DataGrid>
Its always sends the following error in output:
Cannot find source for binding with reference
'ElementName=AllLogs'. BindingExpression:Path=Columns;
DataItem=null; target element is 'MenuItem' (Name=''); target property
is 'ItemsSource' (type 'IEnumerable')
EDIT: Binding with a ComboBox works as expected
<ComboBox ItemsSource="{Binding ElementName=AllLogs, Path=Columns}">
<ComboBox.ItemTemplate>
<DataTemplate>
<CheckBox Content="{Binding Header}"/>
</DataTemplate>
</ComboBox.ItemTemplate>
</ComboBox>
You should set first the DataContext of ContextMenu so that ItemsSource bind to Menu Item can inherit the same DataContext.
<ContextMenu DataContext="{Binding PlacementTarget.DataContext, RelativeSource={RelativeSource Self}}">
<MenuItem Header="Show/Hide Columns"
ItemsSource="{Binding Columns}">
<MenuItem.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding Header}"></TextBlock>
</DataTemplate>
</MenuItem.ItemTemplate>
</MenuItem>
</ContextMenu>
The reason that ContextMenu didn't work but ComboBox did is that ContextMenu is a Popup, that means it's not part of DataGrid's visual tree, so ElementName would not work as ComboBox did. In fact, #user1672994 was vary close to the answer.
<DataGrid x:Name="AllLogs">
<DataGrid.ContextMenu>
<ContextMenu>
<MenuItem Header="Show/Hide Columns"
ItemsSource="{Binding PlacementTarget.Columns, RelativeSource={RelativeSource AncestorType=ContextMenu}}">
<MenuItem.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding Header}"/>
</DataTemplate>
</MenuItem.ItemTemplate>
</MenuItem>
</ContextMenu>
</DataGrid.ContextMenu>
</DataGrid>
The problem/misunderstanding is that ContextMenu isn't a part of a visual tree.
So ContextMenu.PlacementTarget is your "connection" to the UIElement, which is in the visual tree, therefore you have to go via PlacementTarget to access the elements from visual tree.
MSDN about PlacementTarget:
When the ContextMenu is assigned to the FrameworkElement.ContextMenu
or FrameworkContentElement.ContextMenu property, the
ContextMenuService changes this value of this property to the owning
FrameworkElement or FrameworkContentElement when the ContextMenu opens
In answer below you don't have to traverse searching an ancestor type, but do use an UIElement as DataContext for ContextMenu:
<DataGrid.ContextMenu>
<ContextMenu DataContext="{Binding PlacementTarget, RelativeSource={RelativeSource Self}}">
<MenuItem Header="Show/Hide Columns" ItemsSource="{Binding Columns}">
<MenuItem.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding Header}"/>
</DataTemplate>
</MenuItem.ItemTemplate>
</MenuItem>
</ContextMenu>
</DataGrid.ContextMenu>
I don't know the RadGrivView control per say, but the error means that it cannot find an IEnumerable property called "Columns" on your element. Are you sure it is a publicly accessible collection for the control?
ElementName uses VisualTree to find out desired element, it its not part of the current visual tree - up or down as it is with context menu you will get exception.
You could use Binding Source={x:Reference AllLogs} that does not use VisualTree, but unfortunately in your use case you would get exception of circular reference if you use it directly without style.
What you need to use is RelativeSource binding.
<Window.Resources>
<ContextMenu x:Key="headerMenu">
<ContextMenu.Items>
<MenuItem
Header="Show/Hide Columns"
ItemsSource="{Binding Columns, RelativeSource={RelativeSource AncestorType=DataGrid}}">
<MenuItem.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding Header}"/>
</DataTemplate>
</MenuItem.ItemTemplate>
</MenuItem>
</ContextMenu.Items>
</ContextMenu>
<Style TargetType="{x:Type DataGrid}">
<Setter Property="ContextMenu" Value="{StaticResource headerMenu}" />
</Style>
</Window.Resources>
<Grid>
<DataGrid x:Name="AllLogs">
<DataGrid.Columns>
<DataGridTextColumn Header="ID"></DataGridTextColumn>
<DataGridTextColumn Header="Name"></DataGridTextColumn>
</DataGrid.Columns>
</DataGrid>
</Grid>
This would work as well - with Reference:
<Window.Resources>
<ContextMenu x:Key="headerMenu">
<ContextMenu.Items>
<MenuItem
Header="Show/Hide Columns"
ItemsSource="{Binding Source={x:Reference AllLogs}, Path=Columns}">
<MenuItem.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding Header}"/>
</DataTemplate>
</MenuItem.ItemTemplate>
</MenuItem>
</ContextMenu.Items>
</ContextMenu>
<Style TargetType="{x:Type DataGrid}">
<Setter Property="ContextMenu" Value="{StaticResource headerMenu}" />
</Style>
</Window.Resources>
<Grid>
<DataGrid x:Name="AllLogs">
<DataGrid.Columns>
<DataGridTextColumn Header="ID"></DataGridTextColumn>
<DataGridTextColumn Header="Name"></DataGridTextColumn>
</DataGrid.Columns>
</DataGrid>
</Grid>
I'm wondering how to pass the selected item to a command from a treeview / HierarchicalDataTemplate ?
Here is the code that I have so far, it displays the context menu but I haven't bound the commands to it yet. The command binding is the easy part, but how do I tell which node it came from ?
<HierarchicalDataTemplate
DataType="{x:Type viewModel:UsersViewModel}"
ItemsSource="{Binding Children}">
<StackPanel Orientation="Horizontal">
<Image Width="16" Height="16" Margin="3,0" Source="Images\Region.png" />
<TextBlock Text="{Binding UserName}">
<TextBlock.ContextMenu>
<ContextMenu>
<MenuItem Header="Edit" />
<MenuItem Header="Delete"/>
</ContextMenu>
</TextBlock.ContextMenu>
</TextBlock>
</StackPanel>
</HierarchicalDataTemplate>
Just {Binding} should be the whole item.
(To pass it to the Command bind the CommandParameter, in Execute and CanExecute it will become the method parameter (which you then need to cast to your item-type))
I have a context menu in wpf. One of the items in the menu has a sub menu that gets populated from the ItemsSource of the header menu item. This sub menu is a list of commands that can be sent to another portion of the app. The list is basically a mru list restricted to 10 items. I want to add a separator and then a "More" option below the list of 10 items so the user can see the entire list of available commands. I can't seem to figure out how to add these extra items. I can get the list to populate dynamically from the ItemsSource of the parent menu item but I can't seem to figure out how to add the additional items to the bottom of the child menu. I don't want to put them in the items source and the "More" item needs to have its own command.
<MenuItem x:Name="ExecuteCommandMenuItem" Height="22" Style="{StaticResource RightClickMenuItemStyle}"
ItemsSource="{Binding Path=PanelCommands}">
<MenuItem.Header>
<StackPanel Orientation="Horizontal">
<TextBlock Text="Panel Command" HorizontalAlignment="Left" Width="100"/>
</StackPanel>
</MenuItem.Header>
<MenuItem.ItemContainerStyle>
<Style TargetType="MenuItem" BasedOn="{StaticResource RightClickMenuItemStyle}">
<Setter Property="MenuItem.Header" Value="{Binding}" />
<Setter Property="MenuItem.Command" Value="CommonCommands:CommandRepository.ExecutePanelCommand" />
<Setter Property="MenuItem.CommandParameter">
<Setter.Value>
<MultiBinding Converter="{CommonConverter:PanelCommandArgsConverter}">
<MultiBinding.Bindings>
<Binding Path="DataContext" RelativeSource="{RelativeSource FindAncestor,
AncestorType={x:Type ContextMenu}}"/>
<Binding Path="Command" />
</MultiBinding.Bindings>
</MultiBinding>
</Setter.Value>
</Setter>
</Style>
</MenuItem.ItemContainerStyle>
</MenuItem>
Thanks.
<DataGrid x:Class="UICCNET.BaseControls.UserControls.BaseDataGrid"
Tag="{Binding RelativeSource={RelativeSource Self}, Path=Columns}">
<DataGrid.ContextMenu>
<ContextMenu Tag="{Binding RelativeSource={RelativeSource Self},Path=PlacementTarget.Tag}">
<MenuItem Header="Колонки">
<MenuItem >
<MenuItem.Template>
<ControlTemplate>
<ListBox Name="MyComboBox" ItemsSource="{Binding RelativeSource={RelativeSource AncestorType={x:Type ContextMenu}},Path=Tag}">
<ListBox.ItemTemplate>
<DataTemplate>
<CheckBox IsChecked="{Binding Path=Visibility, Mode=TwoWay, Converter={StaticResource BooleanToVisibilityConverter1}}" Content="{Binding Path=Header}"></CheckBox>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
</ControlTemplate>
</MenuItem.Template>
</MenuItem>
</MenuItem>
<MenuItem Header="Друк"></MenuItem>
</ContextMenu>
</DataGrid.ContextMenu>
I dont think you can because it's bound to a source. So either add them to the source OR use a templateselector and do your logic in there. Define a normal template and then a "more" template.
Or, you can do some control nesting like
<menu>
<stackpanel>
<Menu Items>
</menu Items>
<break />
<Button>More</button>
</stackpanel>
</menu>
Sorry this is just off the top of my head. Can you post your XAML?