First UWP in Rust

The first Universal Windows Platform app written in pure Rust.

Note: this project is an early-stage experiment. Code quality is not guaranteed. Crashes or memory leak may occur.

What have been done

• Initialize Application during launch activation
• Metadata provider to work with Frame navigation
• Load XAML (.xbf) contents
• Implementation of IComponentConnector to receive XAML x:Names and event handlers
• Weak references (translated from C++/WinRT projects)
• Implementation of ICustomPropertyProvider for XAML binding support ({Binding} style)
• Pass Windows App Cert Kit (WACK) and distribute from Microsoft Store

What yet to be done

• Idiomatic and safe Rust implementation (let's wait for microsoft/windows-rs#81)
• Generate .xbf file (see microsoft/windows-rs#306 (comment))
• {x:Bind}-style binding (too much boilerplate code)
• CI pipelines

Build and Run

# Build the project using x86_64-pc-windows-msvc default target
cargo build

# Register the package layout
Add-AppxPackage -Register AppxManifest.xml

# Then launch "First UWP in Rust" in your Start Menu

Screenshots

Cross compilation and Packaging

The default targets *-pc-windows-* has some link options unsuitable for UWP applications. A package that contains executable files generated with such target fails WACK in terms of AppContainerCheck and unsupported APIs used. To pass WACK, *-uwp-windows-* targets should be used.

Xargo is recommended for cross-compilation in this project. Using Xargo, it is not necessary to build the whole Rust toolchain in order to consume tier-3 targets. Xargo is not maintained any more. A more recommended way is to use build-std feature in cargo.

Follow the steps below in powershell to build and generate a .appx package:

1. Set up Rust nightly toolchain for this project

rustup toolchain install nightly-2020-08-15
rustup override set nightly-2020-08-15
rustup component add rust-src

2. Build with std-aware cargo

cargo build --release -Z build-std=std,panic_abort --target x86_64-uwp-windows-msvc

i686-uwp-windows-msvc, thumbv7a-uwp-windows-msvc and aarch64-uwp-windows-msvc targets can be used for x64, ARM and ARM64. panic_abort needs to be specified explicitly due to rust-lang/wg-cargo-std-aware#29.

3. Set up environment variables before consuming Windows SDK command line tools

$env:Path+=";${env:ProgramFiles(x86)}\Windows Kits\10\bin\%SDK_VERSION%\x64"

where %SDK_VERSION% is the version of an installed Windows SDK that will provide the necessary command line tools, such as 10.0.18362.0.

4. Create a .appx package

makeappx pack /p FirstUwp_0.0.1.0_x64_Test.appx /v /f .\appxmapping.ini

5. Generate a certificate for self-signing

Start an elevated Powershell prompt, nagivate to the project directory and enter the following:

$cert=New-SelfSignedCertificate -Type Custom -Subject "CN=25C90434-4343-4A2A-BB16-CF3209256BD3" -KeyUsage DigitalSignature -FriendlyName "firstuwpcert" -TextExtension @("2.5.29.37={text}1.3.6.1.5.5.7.3.3", "2.5.29.19={text}")
$data=$cert.Export([System.Security.Cryptography.X509Certificates.X509ContentType]::Pfx)
[io.file]::WriteAllBytes('firstuwp_TemporaryKey.pfx', $data)

6. Import the generated certificate

See https://docs.microsoft.com/en-us/windows/application-management/sideload-apps-in-windows-10#how-do-i-sideload-an-app-on-desktop .

7. Sign the package

signtool sign /v /fd SHA256 /a /f firstuwp_TemporaryKey.pfx FirstUwp_0.0.1.0_x64_Test.appx

Then the package is ready to deploy through Device Portal or App Installer at your option.