Migrating Win32 and UWP to Windows App SDK: Practical Strategies

Getting Started with Windows App SDK: A Step-by-Step Tutorial

Overview

A concise, practical tutorial that walks developers through creating a modern Windows desktop app using the Windows App SDK (formerly Project Reunion). Covers setup, core concepts, UI with WinUI, app lifecycle, packaging, and debugging.

Prerequisites

• OS: Windows 10 (version 1809, build 17763) or later — latest Windows ⁄₁₁ recommended.
• Tools: Visual Studio 2022 (or later) with the “Universal Windows Platform development” and “.NET desktop development” workloads.
• Languages: C# with WinUI (recommended) or C++/WinRT.

Step-by-step outline

1. Install SDK and tools

   • Install Visual Studio with required workloads.
   • Install the latest Windows App SDK NuGet packages or Visual Studio extension.

2. Create a new project

   • In Visual Studio: New Project → “Blank App, Packaged (WinUI in Desktop)” or select a Windows App SDK template.
   • Choose C# (WinUI) or C++ template and create.

3. Understand project structure

   • App.xaml / App.xaml.cs: App lifecycle, startup code.
   • MainWindow.xaml / MainWindow.xaml.cs: Primary UI and code-behind.
   • Package.appxmanifest: App identity and capabilities (for packaging/distribution).
   • Project file (.csproj/.vcxproj): Windows App SDK package references.

4. Build a simple UI (WinUI)

   • Use WinUI controls (NavigationView, CommandBar, ListView).
   • Define layout in XAML; bind to ViewModel for MVVM.
   • Example: Add a NavigationView with pages for Home and Settings.

5. Implement app logic

   • Use async/await for IO.
   • Manage state with ViewModels and a simple dependency injection container.
   • Handle activation and suspension in App.xaml.cs.

6. Use Windows App SDK features

   • Windowing APIs: create and manage multiple windows.
   • App lifecycle & activation: URI and file activation handlers.
   • Notifications: Toast notifications via Notifications API.
   • Community Toolkit: simplified helpers and controls.

7. Debug and run

   • Run locally in Debug mode.
   • Use Visual Studio diagnostics (UI thread, memory, performance) and XAML Hot Reload.

8. Package and sideload

   • Configure Package.appxmanifest with identity and capabilities.
   • Create MSIX package via “Create App Packages” wizard.
   • Sideload or distribute via Microsoft Store.

9. Publish and update

   • Submit MSIX to Microsoft Store or distribute via enterprise channels.
   • Use versioning in MSIX and App Installer for updates.

Tips and best practices

• Prefer WinUI 3 for modern Fluent UI and desktop integration.
• Use MVVM for testable, maintainable code.
• Keep long-running work off UI thread with Task.Run or background services.
• Automate packaging in CI with MSBuild and the Windows App SDK MSIX tooling.

Resources

• Official Windows App SDK docs and samples.
• WinUI Gallery and Community Toolkit on GitHub.

If you want, I can:

• provide a minimal C# WinUI 3 starter project (code files), or
• create a short checklist for publishing to the Microsoft Store. Which would you like?