bo/Workbench/QMonitor/qmonlib.ui/Views/MainView.axaml

<UserControl 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"
             xmlns:vm="clr-namespace:qmonlib.ui.ViewModels"
             mc:Ignorable="d" d:DesignWidth="800" d:DesignHeight="450"
             x:Class="qmonlib.ui.Views.MainView"
             x:DataType="vm:MainViewModel">
  <Design.DataContext>
    <!-- This only sets the DataContext for the previewer in an IDE,
         to set the actual DataContext for runtime, set the DataContext property in code (look at App.axaml.cs) -->
    <vm:MainViewModel />
  </Design.DataContext>
    <!--[+]Split LVL 0-->
    <SplitView IsPaneOpen="true"
               DisplayMode="CompactOverlay"
               CompactPaneLength="32"
               OpenPaneLength="296">
        <SplitView.Pane>
            <Button VerticalAlignment="Top" Width="32" Height="32" HorizontalAlignment="Right">
                <Button.Content>
                    <Image Source="/Images/32/adjust.png" />
                </Button.Content>
            </Button>
            <!-- Filter section -->
        </SplitView.Pane>

        <!--[+]Split LVL 1-->
        <SplitView IsPaneOpen="true"
                   DisplayMode="Inline"
                   CompactPaneLength="32"
                   OpenPaneLength="296" HorizontalAlignment="Right">
            <SplitView.Pane>
                <Button VerticalAlignment="Top" Width="32" Height="32" HorizontalAlignment="Left">
                    <Button.Content>
                        <Image Source="/Images/32/log.png" />
                    </Button.Content>
                </Button>
               <!-- Log section -->
            </SplitView.Pane>
            <!--[-]Split LVL 1-->

            <!-- Content section -->

        </SplitView>
        <!--[-]Split LVL 0-->
    </SplitView>
</UserControl>