Semi.Avalonia/demo/Semi.Avalonia.Demo/Pages/MenuDemo.axaml

<UserControl
    x:Class="Semi.Avalonia.Demo.Pages.MenuDemo"
    xmlns="https://github.com/avaloniaui"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    d:DesignHeight="450"
    d:DesignWidth="800"
    mc:Ignorable="d">
    <StackPanel Spacing="20">
        <Menu>
            <MenuItem Header="_First">
                <MenuItem Header="Standard _Menu Item" InputGesture="Ctrl+A" />
                <MenuItem
                    Header="_Disabled Menu Item"
                    InputGesture="Ctrl+D"
                    IsEnabled="False" />
                <Separator />
                <MenuItem Header="Menu with _Submenu">
                    <MenuItem Header="Submenu _1" />
                    <MenuItem Header="Submenu _2 with Submenu">
                        <MenuItem Header="Submenu Level 2" />
                    </MenuItem>
                    <MenuItem Header="Submenu _3 with Submenu Disabled" IsEnabled="False">
                        <MenuItem Header="Submenu Level 2" />
                    </MenuItem>
                </MenuItem>
                <MenuItem Header="Menu Item with _Checkbox">
                    <MenuItem.Icon>
                        <TextBlock>😊</TextBlock>
                    </MenuItem.Icon>
                </MenuItem>
            </MenuItem>
            <MenuItem Header="_Second">
                <MenuItem Header="Second _Menu Item" />
            </MenuItem>
            <MenuItem Header="Parent">
                <MenuItem Header="Child 1" />
                <MenuItem Header="Child 2" />
                <MenuItem Header="Child 3" />
                <Separator />
                <MenuItem Header="Child 4" />
                <MenuItem Header="Child 5" />
                <MenuItem Header="Child 6" />
                <MenuItem Header="Child 7" />
                <MenuItem Header="Child 8" />
                <MenuItem Header="Child 9" />
                <MenuItem Header="Child 10" />
                <MenuItem Header="Child 11" />
                <MenuItem Header="Child 12" />
                <MenuItem Header="Child 13" />
                <MenuItem Header="Child 14" />
                <MenuItem Header="Child 15" />
                <MenuItem Header="Child 16" />
                <MenuItem Header="Child 17" />
                <MenuItem Header="Child 18" />
                <MenuItem Header="Child 19" />
                <MenuItem Header="Child 4" />
                <MenuItem Header="Child 5" />
                <MenuItem Header="Child 6" />
                <MenuItem Header="Child 7" />
                <MenuItem Header="Child 8" />
                <MenuItem Header="Child 9" />
                <MenuItem Header="Child 10" />
                <MenuItem Header="Child 11" />
                <MenuItem Header="Child 12" />
                <MenuItem Header="Child 13" />
                <MenuItem Header="Child 14" />
                <MenuItem Header="Child 15" />
                <MenuItem Header="Child 16" />
                <MenuItem Header="Child 17" />
                <MenuItem Header="Child 18" />
                <MenuItem Header="Child 19" />
            </MenuItem>
        </Menu>
        <Border Theme="{DynamicResource CardBorder}">
            <Border.ContextMenu>
                <ContextMenu>
                    <MenuItem Header="Standard _Menu Item" InputGesture="Ctrl+A" />
                    <MenuItem
                        Header="_Disabled Menu Item"
                        InputGesture="Ctrl+D"
                        IsEnabled="False" />
                    <Separator />
                    <MenuItem Header="Menu with _Submenu">
                        <MenuItem Header="Submenu _1" />
                        <MenuItem Header="Submenu _2" />
                    </MenuItem>
                    <MenuItem Header="Menu Item with _Checkbox">
                        <MenuItem.Icon>
                            <CheckBox
                                Padding="0"
                                BorderThickness="0"
                                IsChecked="True"
                                IsHitTestVisible="False" />
                        </MenuItem.Icon>
                    </MenuItem>
                    <MenuItem Header="Menu Item that won't close on click" StaysOpenOnClick="True" />
                </ContextMenu>
            </Border.ContextMenu>
            <TextBlock Text="Right Click to show Context Menu" />
        </Border>
        <Border Theme="{DynamicResource CardBorder}">
            <Border.ContextFlyout>
                <MenuFlyout>
                    <MenuItem Header="Standard _Menu Item" InputGesture="Ctrl+A" />
                    <MenuItem
                        Header="_Disabled Menu Item"
                        InputGesture="Ctrl+D"
                        IsEnabled="False" />
                    <Separator />
                    <MenuItem Header="Menu with _Submenu">
                        <MenuItem Header="Submenu _1" />
                        <MenuItem Header="Submenu _2" />
                    </MenuItem>
                    <MenuItem Header="Menu Item with _Checkbox">
                        <MenuItem.Icon>
                            <CheckBox
                                Padding="0"
                                BorderThickness="0"
                                IsChecked="True"
                                IsHitTestVisible="False" />
                        </MenuItem.Icon>
                    </MenuItem>
                </MenuFlyout>
            </Border.ContextFlyout>
            <TextBlock Text="Right Click to show Context Flyout" />
        </Border>
    </StackPanel>
</UserControl>