Bindings to the Swift programming language

[PetaSoft]

A Swift compiler exists not only for the Apple ecosystem but also for Windows and Linux but SwiftUI can only be used for Apple devices. Furthermore, Qt is a cross plattform framework, but only supports C++ and Python. Maybe, Slint can fill a gap, and become a cross plattform framework for Swift. Furthermore, I am not aware of any UI framework that supports Swift on Windows.

[ogoffart]

We aim to support multiple programming language in the future. That said, Swift is not a priority for us considering that Swift already has a natural UI framework and that Swift is not really popular on Linux and Windows. But if someone were to contribute Swift bindings, we'd happily assist them.

[thbonk]

We aim to support multiple programming language in the future. That said, Swift is not a priority for us considering that Swift already has a natural UI framework and that Swift is not really popular on Linux and Windows. But if someone were to contribute Swift bindings, we'd happily assist them.

@ogoffart Is there a guide how to develop bindings for other programming languages?

[ogoffart]

We don't have such a guide.

There is two things to do:

1. wrap the API to the slint runtime
2. Create a code generator for the swift language.

For example, for C++, the wrapper is in https://github.com/slint-ui/slint/tree/master/api/cpp , and the code generator in https://github.com/slint-ui/slint/blob/master/internal/compiler/generator/cpp.rs

The best would be, I guess, to look at that and try to do something similar for swift.

If you are interested, I'd be happy to answer any questions you have, here or by chat or so.

[illucid-matthew]

I've spent a few weeks taking a crack at it. I'm no longer interested in pursuing this, but if someone else wants to this could be a good starting point.

Here's my result: https://github.com/illucid-matthew/slint-swift-bindings

The main things I accomplished are:

• Importing the private cbindgen API into Swift
• Integrating the Slint event loop and main-thread requirements into Swift's concurrency model
• Basic application framework
  • Create a type that conforms to SlintApp
  • Write a start() method to initialize your UI
  • Event loop starts when start() is finished

Example:

import SlintUI

@main
struct ExampleApp: SlintApp {
    static func start() {
        print("⏰ Setting up a timer to fire in three seconds…")
        
        let timer = SlintTimer()
        timer.willRun(after: 3000) {
            print("⏰ Timer fired!")
        }
    }
}

I also converted timer and callback, but the latter runs into a strange bug that that I'm not inclined to track down.

Beyond that, there are a few unfinished core library types, and a minor attempt to create bindings for the interpreter API.

[tronical]

Great that you managed to get that far with Swift bindings - thanks for sharing!