xilem/masonry

Masonry

Foundational framework for Rust GUI libraries

Masonry gives you a platform to create a window (using winit as a backend) with a tree of widgets. It also gives you tools to inspect that widget tree at runtime, write unit tests on it, and generally have an easier time debugging and maintaining your app.

The framework is not opinionated about what your user-facing abstraction will be: you can implement immediate-mode GUI, the Elm architecture, functional reactive GUI, etc, on top of Masonry. See Xilem as an example of reactive UI built on top of Masonry.

Masonry was originally a fork of Druid that emerged from discussions within the Linebender community about what it would look like to turn Druid into a foundational library.

Masonry can currently be considered to be in an alpha state. Lots of things need improvements, e.g. text input is janky and snapshot testing is not consistent across platforms.

Example

The to-do-list example looks like this:

use masonry::app_driver::{AppDriver, DriverCtx};
use masonry::dpi::LogicalSize;
use masonry::widget::{Button, Flex, Label, Portal, RootWidget, Textbox, WidgetMut};
use masonry::{Action, WidgetId};
use winit::window::Window;

const VERTICAL_WIDGET_SPACING: f64 = 20.0;

struct Driver {
    next_task: String,
}

impl AppDriver for Driver {
    fn on_action(&mut self, ctx: &mut DriverCtx<'_>, _widget_id: WidgetId, action: Action) {
        match action {
            Action::ButtonPressed => {
                let mut root: WidgetMut<RootWidget<Portal<Flex>>> = ctx.get_root();
                let mut root = root.get_element();
                let mut flex = root.child_mut();
                flex.add_child(Label::new(self.next_task.clone()));
            }
            Action::TextChanged(new_text) => {
                self.next_task = new_text.clone();
            }
            _ => {}
        }
    }
}

fn main() {
    let main_widget = Portal::new(
        Flex::column()
            .with_child(
                Flex::row()
                    .with_flex_child(Textbox::new(""), 1.0)
                    .with_child(Button::new("Add task")),
            )
            .with_spacer(VERTICAL_WIDGET_SPACING),
    );

    let window_size = LogicalSize::new(400.0, 400.0);
    let window_attributes = Window::default_attributes()
        .with_title("To-do list")
        .with_resizable(true)
        .with_min_inner_size(window_size);

    masonry::event_loop_runner::run(
        masonry::event_loop_runner::EventLoop::with_user_event(),
        window_attributes,
        RootWidget::new(main_widget),
        Driver {
            next_task: String::new(),
        },
    )
    .unwrap();
}

Community

Discussion of Masonry development happens in the Linebender Zulip, specifically the #masonry stream. All public content can be read without logging in.

Contributions are welcome by pull request. The Rust code of conduct applies.

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache 2.0 license, shall be licensed as noted in the License section, without any additional terms or conditions.

License

Licensed under the Apache License, Version 2.0 (LICENSE or http://www.apache.org/licenses/LICENSE-2.0)