KeyNotFoundException during create region in Shell.xaml - wpf

Question

I just started with PRISM, and encounter a exception I can't resolve.
<Window x:Class="Workplace.Shell"
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:prism="http://www.codeplex.com/prism"
mc:Ignorable="d"
Title="MainWindow" Height="350" Width="525">
<Grid>
<Grid Name="Header" prism:RegionManager.RegionName="Header">
</Grid>
</Grid>
</Window>
.
using Autofac;
using Prism.Autofac;
using Prism.Modularity;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
namespace Workplace
{
class Bootstrapper : AutofacBootstrapper
{
protected override DependencyObject CreateShell()
{
return new Shell();
}
protected override void InitializeShell()
{
base.InitializeShell();
Application.Current.MainWindow = (Window) this.Shell;
Application.Current.MainWindow.Show();
}
protected override void ConfigureModuleCatalog()
{
base.ConfigureModuleCatalog();
}
}
}
After run I get exception:
KeyNotFoundException: The IRegionAdapter for the type
System.Windows.Controls.Grid is not registered in the region adapter
mappings. You can register an IRegionAdapter for this control by
overriding the ConfigureRegionAdapterMappings method in the
bootstrapper.
Okey but AutofacBootstrapper class doesn't have any metod named ConfigureRegionAdapterMappings to override.
First I think something is wrong with AutofacBootstrapper, but even if I change it to UnityBootstrapper problem still exist. However second one allow me to override ConfigureRegionAdapterMappings

Answer 1

A Grid isn't a useful host for a region. Try using a ContentControl instead.
Of course, you can create and register a custom region adapter if you absolutely want to use the Grid, but I cannot really see any benefit.