Interktion im WPF erweitert

DaSaSo.Wpf/View/Buildingsites/BuildingSiteListView.xaml

@@ -3,13 +3,14 @@
              xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
              xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
              xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
-             xmlns:local="clr-namespace:DaSaSo.Wpf.View.Buildingsites"
+             xmlns:local="clr-namespace:DaSaSo.Wpf.View.Buildingsites" xmlns:viewmodel="clr-namespace:DaSaSo.ViewModel;assembly=DaSaSo.ViewModel" d:DataContext="{d:DesignInstance Type=viewmodel:BuildingsiteListViewModel}"
              mc:Ignorable="d" 
              d:DesignHeight="450" d:DesignWidth="800">
     <Grid>
         <StackPanel>
             <DataGrid ItemsSource="{Binding Buildingsites}" SelectedItem="{Binding SelectedBuildingsite}" />
             <Button Content="Selektiere" Command="{Binding SelectCommand}" />
+            <Button Content="Hinzufügen" Command="{Binding AddCommand}" />
         </StackPanel>
     </Grid>
 </UserControl>