For years, Microsoft has been trying to get developers to build Windows apps using its newer Universal Windows Platform (UWP) rather
than the old-school Win32. At the online-only Build 2020 conference, the company
unveiled Project Reunion, which is intended to wed the two.
The older style still dominates the Windows applications landscape, but UWP
apps (as their name indicates) can easily be adapted to run on not only Windows
computers, but also on Xbox consoles, the web, and even the HoloLens. The downside is
that they don’t run on the discontinued Windows 7 OS, which lacks an
Project Reunion can also endow
UWP apps with is support for newer input options like touch and pen, in addition to
mouse and keyboard. It lets coders add swipe gestures that work not only on
a Windows 10 touch screen but also on an iPad.
A lot of this cross-platform support comes from one of Project
Reunion’s main components: WinUI
3, a UI framework that uses Fluent-design controls and styles. Its predecessor
was only available for UWP apps, but the new version supports Win32 code as
well. According to Microsoft, “WinUI 3 decouples
the XAML, Composition, and Input layers of Windows 10.” In his Build demo, Kevin Gallo, head of developer platform at Microsoft, also showed a nifty input box trick, in which you can use math operators and
the app does the math for you. So, if the form entry is for square footage, you
can just enter 12×21 and have the app calculate it.
Creating a modern UWP app with Project Reunion (Image: Microsoft)
At Build 2017, I reported on tools the
company had produced that make it easy to convert
Win32 apps to UWP apps. Reunion extends and expands on this initiative,
adding Microsoft 365 Graph and WebView components as well as the
compartmentalization of apps through things like NuGet, a shared repository for .NET packages. Another current component of Project Reunion
is MSIX, a
modern app packaging tool.
WebView2 is now in preview, with the first stable release “rapidly approaching,” Gallo says. Not only does WebView2 let you access and display web content in your app, but
also PDFs. As with WinUI 3, WebView2 is decoupled from Windows, meaning it doesn’t
require a particular Windows version. As you might expect, WebView2 is powered
by the new Edge browser build on Chromium code.
Microsoft’s Kevin Gallo shows new coding tools at Build 2020 (Image: Microsoft)
The last current component of Project Reunion is Windows
Virtual Desktop (WVD). According to Gallo, “WVD empowers remote work and education
solutions for your Windows apps on iOS, Mac, Android, Linux, and of course, Windows.”
It adapts WinUI programs to present a native look on those devices and can take
advantage of the tablet’s cameras and mic as well. WVD also benefits from
Azure’s scalability, letting you add lots of users, while MSIX will enable
simplified deployment to these non-Windows platforms as well as to Windows 10.
Interested developers can check out the various pieces of Project
Reunion code for themselves at its GitHub repository.