VB WinUI 3 Demos

Demonstrates how to use WinUI 3 in Visual Basic .NET projects.

Progress

• No C# or C++ projects for startup
• Load XamlControlsResources from Microsoft.UI.Xaml.Controls automatically
• Use a custom Sub Main - You can enable high DPI, add dynamic dependencies or add reg-free WinRT support by editing Program.vb.
• Allow Windows Forms integration, such as registering HostServices.VBHost at startup
• Make sure Mica and Acrylic are working as expected on Windows 11
• Workaround blocking bugs of the WinUI 3 XAML compiler - Generate Xbf files and VB source files
• Workaround trivial bugs of the WinUI 3 XAML compiler - Generate 99% correct VB source files
• Publish a NuGet package that contains VB specific build transitive files, so any VB projects will be able to use WinUI 3 without editing *.vbproj manually.
• Publish a VSIX to add VB WinUI 3 templates to Visual Studio.
• Write a new VB application framework for WinUI 3 - Allow users to delete Program.vb and use events to configure the App in the Application class
• Write a new VB "My extension" for WinUI 3 - Enable My.* for WinUI 3 specific things

Environment

• Visual Studio 2022 with Windows Desktop and UWP development workloads
• Windows 10 21H2 or Windows 11

How does it work

Approach 1: Use the default WinUI VB XAML compiler

The MSBuild target files of WinUI 3 need some hacking to support Visual Basic. VB projects need to import the following target file to use WinUI 3.

WinUI3.VisualBasic.targets

<Project>

  <PropertyGroup>
    <!-- Workaround for conflicts with WPF -->
    <ImportFrameworkWinFXTargets>true</ImportFrameworkWinFXTargets>
    <!-- Workaround for wrong entry point code generated by WinUI 3 -->
    <DefineConstants>DISABLE_XAML_GENERATED_MAIN</DefineConstants>
  </PropertyGroup>

  <!-- Workaround for XamlPreCompile compilation errors -->
  <Target Name="SpecifyVBRuntimeForXamlPreCompile" BeforeTargets="XamlPreCompile">
    <PropertyGroup>
      <VBRuntime>None</VBRuntime>
    </PropertyGroup>
  </Target>
  
</Project>

Approach 2: Use the WinUI C# XAML compiler and code converter

Stopped with error. See [XamlLanguageConverter].

Approach 3: Use a custom XAML compiler

WIP. See [Custom XAML compiler].

Samples

BatchFfmpegWinUI

A mp4 video to h265 transcoder.

It converts .mp4 and .mkv videos to h265 encoding by calling H265.bat.

Status

Finished. Tested with WinUI3 v1.3.230602002 and .NET SDK v7.0.7.

How to use it

• Install ffmpeg to %programfiles%\ffmpeg\bin. If you have installed it in a different location, please add it to %PATH%.
• Open BatchFfmpegWinUI.sln with Visual Studio.
• Set BatchFfmpegWinUI_Pack as startup project and run.
• Drag and drop .mp4 or .mkv files.
• Press the "Convert" button and wait.

XamlLanguageConverter

Demonstrates how to use MSBuild extension points to invoke the C# XAML compiler and start a code converter to convert the C# output to VB.

Status

Stopped with error. Because it has severe performance issues.

Custom XAML compiler

Use the XamlCompilerTaskPath MSBuild property to replace the path of Microsoft.UI.Xaml.Markup.Compiler.dll with a custom XAML compiler.

The source code of this part won't be published until Microsoft uploads the source code of Microsoft.UI.Xaml.Markup.Compiler.

Status

WIP

WinUIGallery

A VB version of WinUIGallery v1.1. It uses the C# XAML converter until the official VB WinUI3 XAML converter works correctly.

Status

WIP, depends on XamlLanguageConverter.