Scrollviewer with dynamic height and menu below - wpf

Question

I cannot find any example how to implement a scrollviewer that contains a form, with the save/cancel buttons directly underneath and not separated at the bottom of the window here is a simple layout. I need to support resizing the window. I have many different lengths of forms, I want the scrollviewer to be as small as possible, and fill available space only if needed (if the form is larger). I don't want the buttons to always be pushed to the bottom of the window Not like this!, but to hug closer to the form (in the case of a shorter form) Something like this.
In my grid, I have a row for the ScrollViewer, a row for the buttons, and a row to fill remaining space (if any).
I understand that by setting the row height=Auto kills the ScrollViewer. How can I implement this then? Is this even possible?
Jeff -> Here is an image showing the window height increased. And an image showing the window height decreased, the buttons can disappear from view, and the scrollviewer overflows so that you cannot see all of it
<Window x:Class="WpfAppRenderPathGeometry.MainWindow"
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"
xmlns:local="clr-namespace:WpfAppRenderPathGeometry"
mc:Ignorable="d"
Title="MainWindow" Height="500" Width="800">
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="Auto" x:Name="ScrollRow"/>
<RowDefinition Height="80" x:Name="ButtonsRow"/>
<RowDefinition Height="*" x:Name="SpaceRow"/>
</Grid.RowDefinitions>
<ScrollViewer x:Name="MyScroll" VerticalScrollBarVisibility="Visible">
<Grid x:Name="MyForm">
<Grid.RowDefinitions>
<RowDefinition />
<RowDefinition />
<RowDefinition />
<RowDefinition />
<RowDefinition />
<RowDefinition />
<RowDefinition />
<RowDefinition />
<RowDefinition />
<RowDefinition />
<RowDefinition />
<RowDefinition />
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition/>
<ColumnDefinition/>
</Grid.ColumnDefinitions>
<TextBlock Grid.Row="0" Grid.Column="0">LABEL</TextBlock>
<TextBox Grid.Column="1"></TextBox>
<TextBlock Grid.Row="1" Grid.Column="0">LABEL</TextBlock>
<TextBox Grid.Row="1" Grid.Column="1"></TextBox>
<TextBlock Grid.Row="2" Grid.Column="0">LABEL</TextBlock>
<TextBox Grid.Row="2" Grid.Column="1"></TextBox>
<TextBlock Grid.Row="3" Grid.Column="0">LABEL</TextBlock>
<TextBox Grid.Row="3" Grid.Column="1"></TextBox>
<TextBlock Grid.Row="4" Grid.Column="0">LABEL</TextBlock>
<TextBox Grid.Row="4" Grid.Column="1"></TextBox>
<TextBlock Grid.Row="5" Grid.Column="0">LABEL</TextBlock>
<TextBox Grid.Row="5" Grid.Column="1"></TextBox>
<TextBlock Grid.Row="6" Grid.Column="0">LABEL</TextBlock>
<TextBox Grid.Row="6" Grid.Column="1"></TextBox>
<TextBlock Grid.Row="7" Grid.Column="0">LABEL</TextBlock>
<TextBox Grid.Row="7" Grid.Column="1"></TextBox>
<TextBlock Grid.Row="8" Grid.Column="0">LABEL</TextBlock>
<TextBox Grid.Row="8" Grid.Column="1"></TextBox>
<TextBlock Grid.Row="9" Grid.Column="0">LABEL</TextBlock>
<TextBox Grid.Row="9" Grid.Column="1"></TextBox>
<TextBlock Grid.Row="10" Grid.Column="0">LABEL</TextBlock>
<TextBox Grid.Row="10" Grid.Column="1"></TextBox>
<TextBlock Grid.Row="11" Grid.Column="0">LABEL</TextBlock>
<TextBox Grid.Row="11" Grid.Column="1"></TextBox>
</Grid>
</ScrollViewer>
<StackPanel Orientation="Horizontal" HorizontalAlignment="Center" Grid.Row="1">
<Button>CANCEL</Button>
<Button>SAVE</Button>
</StackPanel>
</Grid>
</Window>

Answer 1

As an example, I think this will do what you want - just adjust as you need.
I adjusted again but I am not sure I understand your intent.
<Window
x:Class="WpfSubDivideWindow.ScrollViewWindow"
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:local="clr-namespace:WpfSubDivideWindow"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:MyNamespace="clr-namespace:WpfSubDivideWindow"
xmlns:sys="clr-namespace:System;assembly=mscorlib"
Title="ScrollViewWindow"
Width="800"
Height="350"
mc:Ignorable="d"
>
<Window.Resources>
<Style x:Key="tbk.Base"
TargetType="TextBlock"
>
<Setter Property="HorizontalAlignment" Value="Right" />
<Setter Property="VerticalAlignment" Value="Center" />
<Setter Property="FontSize" Value="18" />
<Setter Property="FontWeight" Value="Bold" />
<Setter Property="Padding" Value="0" />
<Setter Property="Margin" Value="0,12,20,12" />
</Style>
<Style x:Key="tbx.Base"
TargetType="TextBox"
>
<Setter Property="HorizontalAlignment" Value="Stretch" />
<Setter Property="VerticalAlignment" Value="Center" />
<Setter Property="FontSize" Value="18" />
<Setter Property="Padding" Value="0" />
<Setter Property="Margin" Value="0,12,60,12" />
</Style>
<Style x:Key="Btn.Base"
TargetType="Button"
>
<Setter Property="HorizontalAlignment" Value="Stretch" />
<Setter Property="VerticalAlignment" Value="Center" />
<Setter Property="FontSize" Value="18" />
<Setter Property="Padding" Value="0" />
<Setter Property="Background" Value="DarkGreen" />
<Setter Property="Foreground" Value="White" />
<Setter Property="Margin" Value="20,0,0,0" />
<Setter Property="Height" Value="36" />
<Setter Property="Width" Value="90" />
</Style>
</Window.Resources>
<Grid>
<Grid.RowDefinitions>
<RowDefinition x:Name="ScrollRow" MaxHeight="{Binding ElementName=MyForm, Path=ActualHeight}" />
<RowDefinition x:Name="ButtonsRow" Height="80" />
<RowDefinition x:Name="SpaceRow" Height="Auto" />
</Grid.RowDefinitions>
<ScrollViewer x:Name="MyScroll"
HorizontalScrollBarVisibility="Auto"
VerticalScrollBarVisibility="Visible"
>
<Grid x:Name="MyForm"
Background="Moccasin"
>
<Grid.RowDefinitions>
<RowDefinition Height="*" />
<RowDefinition Height="*" />
<RowDefinition Height="*" />
<RowDefinition Height="*" />
<RowDefinition Height="*" />
<RowDefinition Height="*" />
<RowDefinition Height="*" />
<RowDefinition Height="*" />
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="160" />
<ColumnDefinition />
</Grid.ColumnDefinitions>
<TextBlock
Grid.Column="0"
Grid.Row="0"
Text="INDEX"
Style="{StaticResource tbk.Base}"
/>
<TextBox
Grid.Column="1"
Grid.Row="0"
Style="{StaticResource tbx.Base}"
/>
<TextBlock
Grid.Column="0"
Grid.Row="1"
Text="INDEX"
Style="{StaticResource tbk.Base}"
/>
<TextBox
Grid.Column="1"
Grid.Row="1"
Style="{StaticResource tbx.Base}"
/>
<TextBlock
Grid.Column="0"
Grid.Row="2"
Text="INDEX"
Style="{StaticResource tbk.Base}"
/>
<TextBox
Grid.Column="1"
Grid.Row="2"
Style="{StaticResource tbx.Base}"
/>
<TextBlock
Grid.Column="0"
Grid.Row="3"
Text="INDEX"
Style="{StaticResource tbk.Base}"
/>
<TextBox
Grid.Column="1"
Grid.Row="3"
Style="{StaticResource tbx.Base}"
/>
<TextBlock
Grid.Column="0"
Grid.Row="4"
Text="INDEX"
Style="{StaticResource tbk.Base}"
/>
<TextBox
Grid.Column="1"
Grid.Row="4"
Style="{StaticResource tbx.Base}"
/>
<TextBlock
Grid.Column="0"
Grid.Row="5"
Text="INDEX"
Style="{StaticResource tbk.Base}"
/>
<TextBox
Grid.Column="1"
Grid.Row="5"
Style="{StaticResource tbx.Base}"
/>
<TextBlock
Grid.Column="0"
Grid.Row="6"
Text="INDEX"
Style="{StaticResource tbk.Base}"
/>
<TextBox
Grid.Column="1"
Grid.Row="6"
Style="{StaticResource tbx.Base}"
/>
<TextBlock
Grid.Column="0"
Grid.Row="7"
Text="INDEX"
Style="{StaticResource tbk.Base}"
/>
<TextBox
Grid.Column="1"
Grid.Row="7"
Style="{StaticResource tbx.Base}"
/>
</Grid>
</ScrollViewer>
<StackPanel
Grid.Row="1"
HorizontalAlignment="Center"
Orientation="Horizontal"
>
<Button
Content="Cancel"
Margin="0"
Style="{StaticResource Btn.Base}"
/>
<Button
Content="Save"
Style="{StaticResource Btn.Base}"
/>
</StackPanel>
</Grid>
</Window>