如何从窗口中删除空菜单栏

Question

在我的应用程序中，我正在使用功能区，现在，我有这个不必要的空间：

可以删除该空间吗？以下是窗口的基本代码大纲：

<Window 
    xmlns:my="http://schemas.microsoft.com/winfx/2006/xaml/presentation/ribbon" 
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    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" 
    mc:Ignorable="d" x:Class="myproj.gebnot"
    Title="My Project"  
    WindowStartupLocation="CenterScreen" 
    Width="22cm" 
    WindowState="Normal" >

    <DockPanel LastChildFill="True">
        <my:Ribbon ShowQuickAccessToolBarOnTop="False" DockPanel.Dock="Top" >
            ....
        </my:Ribbon>

        <ScrollViewer Name="scroller" 
            HorizontalScrollBarVisibility="Auto" 
            VerticalScrollBarVisibility="Auto" > 

            <Canvas Name="PageCanvas"  
              HorizontalAlignment="Left"  
              VerticalAlignment="Top" 
              Width="21cm" Height="29.7cm" 
              KeyboardNavigation.TabNavigation="Cycle">
                ...