January 31, 2024 by Slint Team

Slint 1.4 Released with additional Look and Improved APIs

We're excited to announce the release of Slint 1.4, featuring a brand new style and many qualify of life improvements.

New Cosmic Style

Screenshot of Widgets Gallery in Cosmic Style

We offer four different styles behind a common widgets API. In this release, we've added a new friend to the group: Say hello to Cosmic Style, which implements the look and feel of System 76's Pop!_OS. Check out Cosmic style in our WASM Demo. We think it's slick 😍.

New APIs

Thanks to your feedback and contributions, this release fills in the gap with many new functions that were previously missing:

  • Use TouchArea's new double-clicked callback to conveniently handle double click events in your UI.
  • Adapt your custom controls to match the selected widget style with the new Palette singleton.
  • Programmatically show a slint::Window fullscreen with the new set_fullscreen(bool) function. (Thanks qhua948)
  • Keep the event loop alive when there are no windows with new run_event_loop_until_quit() function. This is for the folks who'd like to create system tray apps: We heard you 👍
  • Style your icon based on the text color with Button's new colorize-icon property.
  • C++: Empty your slint::VectorModel with clear().

Binary Packages for JavaScript API

Previously, using Slint with Node.js required a Rust installation, for Slint to be compiled from source code. With this release, we're adding binaries for macOS, Windows, and Linux. This removes the need to compile Slint from source and speeds up the npm install step.

As a bonus, this means that you can also use Slint from Deno, the next-generation JavaScript run-time. Skip the npm install entirely:

import * as slint from "npm:slint-ui";
let ui = slint.loadSource(`
    import { AboutSlint } from "std-widgets.slint";
    export component Demo inherits Window { AboutSlint {} } 
`, "main.slint");
let demo = new ui.Demo();
await demo.run();
deno run --allow-read --allow-ffi --allow-sys index.ts

Progress on Android Port and LinuxKMS Backend

Virtual Keyboard in Slint on Android

We continue to work on the NLNet funded Android port. We now have support for virtual keyboard input. The Android backend is not yet stable in this release, but you can already try it out using our private API.

For the experimental LinuxKMS backend, we've added support for display rotation. Set the SLINT_KMS_ROTATION environment variable to rotate your application.

Smoother Development Experience

We want you to enjoy developing with Slint. So, we've made various tweaks that ensure a smoother development experience:

  • Parentheses in if statements are now optional. Rust developers rejoice 😍. (Thanks Chen1Plus)
  • Auto-completion in the LSP now preserves your choice of dash vs. underscore in identifiers.
  • We optimized the Slint Compiler to produce more efficient output, speeding up application compile times up to 50%.
  • If you're a Neovim user on macOS, installing slint-lsp now uses pre-built binaries.
  • Improved live-preview: Pick elements with your mouse by enabling the "Pick Mode", then click/ctrl+click/double-click to select an element in the same file/any file/underneath.


Updating to Slint 1.4 is effortless:

  • Rust: Run cargo update to bring your application up-to-date.
  • C++: If you're using FetchContent with CMake, update the GIT_TAG entry in CMakeLists.txt to v1.4.0 or release/1.4 for automatic tracking of 1.4.x releases.
  • Node.js: Run npm update slint-ui to bring your package.json up-to-date.

Closing Thoughts

We would like to express our gratitude to our contributors - qhua948, Chen1Plus, MiKom, chfogelman, BrandonXLF, nununoisy, task-jp, MicroCBer, and Horbin-Magician, as well as everyone who reported bugs (more than 30 fixed in this release). Thank you for being a part of the Slint community ❤️.

Explore the new features of Slint 1.4! 🌟

Your feedback is invaluable to us. Please reach out if you encounter any issues or notice missing functionality. Get in touch via our GitHub pages, email, or via chat on our Mattermost instance.


Slint is a declarative GUI toolkit to build native user interfaces for desktop and embedded applications written in Rust, C++, or JavaScript. Find more information at https://slint.dev/ or check out the source code at https://github.com/slint-ui/slint