Enable nullability in MPF

CHANGELIST.md

@@ -10,6 +10,7 @@
 - Enable nullability in Check
 - Remove all but .NET 6 for AppVeyor packaging
 - Place message boxes at center of main window (Deterous)
+- Enable nullability in MPF
 
 ### 2.7.0 (2023-10-11)
 

MPF/App.xaml.cs

@@ -1,16 +1,7 @@
-using System.Windows;
-
-namespace MPF
+namespace MPF
 {
     /// <summary>
     /// Interaction logic for App.xaml
     /// </summary>
-    /// <remarks>
-    /// This application is not fully MVVM. The following steps are needed to get there:
-    /// - Use commands instead of event handlers, where at all possible
-    /// - Reduce the amount of manual UI adjustments needed, instead binding to the view models
-    /// </remarks>
-    public partial class App : Application
-    {
-    }
+    public partial class App : System.Windows.Application { }
 }

MPF/MPF.csproj

@@ -15,6 +15,10 @@
     <InternalsVisibleTo>MPF.Test</InternalsVisibleTo>
   </PropertyGroup>
 
+	<PropertyGroup Condition="'$(TargetFramework)'!='net48'">
+		<Nullable>enable</Nullable>
+	</PropertyGroup>
+
   <ItemGroup>
     <Resource Include="Images\Icon.ico" />
   </ItemGroup>