(─━┘_└━─)/ 머리만1톤(Head1Ton)

<Window x:Class="WPFApplication.Window1"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="Window1"
    Height="300"
    Width="500"
    >
    <Grid>
        <Grid.RowDefinitions>
            <RowDefinition Height="50*" />
            <RowDefinition Height="Auto" />
            <RowDefinition Height="50*" />
        </Grid.RowDefinitions>
        <StackPanel Grid.Row="0" Grid.Column="1" Background="Tan"/>
        <GridSplitter Grid.Row="1"
              HorizontalAlignment="Stretch"
              VerticalAlignment="Center"
              Background="Black"
              ShowsPreview="True"
              Height="5"
           />
        <StackPanel Grid.Row="2" Grid.Column="0" Background="Brown"/>

    </Grid>

</Window>