GridSplitter as Entire Column or Row
<Window x:Class="SDKSample.Window1" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" Title="Row GridSplitter Example"> <Grid > <Grid.RowDefinitions> <RowDefinition Height="150"/> </Grid.RowDefinitions> <Grid.ColumnDefinitions> <ColumnDefinition/> <ColumnDefinition Width="Auto" /> <ColumnDefinition/> </Grid.ColumnDefinitions> <StackPanel Grid.Row="0" Grid.Column="0" Background="Blue"/> <GridSplitter Grid.Column="1" HorizontalAlignment="Center" VerticalAlignment="Stretch" Background="Black" ShowsPreview="True" Width="5" /> <Grid Grid.Row="0" Grid.Column="2"> <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> </Grid> </Window>