Dialog Surface for Slint

KitDialogSurface · Slint Kit 0.3.0

Modal host managing the scrim, close requests and focus traversal.

Try the component

Download the complete project, extract it and run cargo run --locked in its folder. Rust 1.92+; Slint Kit 0.3.0 from crates.io. You can also copy the four files below.

Open project details, archive the project, or dismiss with Escape. Closing restores the opener’s focus.

ui/app.slint

export { KitFormValidation, HtmlInputKind, NumberInputFormat, KitInputConstraints, KitValidationResult, KitValidityState } from "@kit/kit.slint";
// SPDX-License-Identifier: GPL-3.0-or-later
import { KitDialogSurface, KitDialogPanel, KitButton, DialogTabPolicy, CloseReason, KitTheme, KitThemes } from "@kit/kit.slint";
export component App inherits Window {
    title: "KitDialogSurface example";
    preferred-width: 520px;
    preferred-height: 400px;
    max-width: 100000px;
    max-height: 100000px;
    background: root.theme.canvas;
    in-out property <KitTheme> theme: KitThemes.light;
    in property <bool> showing;
    in property <string> result: "Project active";
    callback open();
    callback close(CloseReason);
    callback archive();
    public function focus-opener() { opener.take-focus(); }
    public function focus-dialog() { archive-button.take-focus(); }

    VerticalLayout {
        padding: 24px;
        spacing: 16px;
        alignment: start;
        opener := KitButton { theme: root.theme; text: "Open project details"; disabled: root.showing; activated => { root.open(); } }
        Text { text: root.result; color: root.theme.text-primary; }

    }
    modal := KitDialogSurface {
        theme: root.theme; width: root.width; height: root.height;
        state: { open: root.showing, topmost: root.showing, busy: false };
        tab-policy: DialogTabPolicy.native;
        dismiss(reason) => { root.close(reason); }
        KitDialogPanel {
            theme: root.theme; accessible-name: "Archive project";
            width: min(420px, parent.width - 40px); height: 180px;
            x: (parent.width - self.width) / 2; y: (parent.height - self.height) / 2;
            VerticalLayout { padding: 20px; spacing: 16px; alignment: start;
            Text { text: "Archive this project?"; color: root.theme.text-primary; font-size: 20px * root.theme.text-scale; wrap: word-wrap; }
            archive-button := KitButton { theme: root.theme; text: "Archive project"; activated => { root.archive(); } }
            }
        }
    }
}

src/main.rs

// SPDX-License-Identifier: GPL-3.0-or-later
use slint::ComponentHandle;
use slint_kit::{OverlayStack, OverlaySpec, OverlayId, DismissReason, CloseResult};
mod ui { slint::include_modules!(); }
fn main() -> Result<(), slint::PlatformError> {
    let app = ui::App::new()?;
    slint_kit::init_form_validation!(ui, app);
    let overlays = std::rc::Rc::new(std::cell::RefCell::new(OverlayStack::new()));
    let weak = app.as_weak();
    let stack = overlays.clone();
    app.on_open(move || {
        if let Some(app) = weak.upgrade() {
            if stack.borrow().is_empty() {
                stack.borrow_mut().push(OverlaySpec::new(OverlayId(1), None, true)).expect("single modal");
                app.set_showing(true);
                app.invoke_focus_dialog();
            }
        }
    });
    let weak = app.as_weak();
    let stack = overlays.clone();
    app.on_close(move |reason| {
        let reason = match reason {
            ui::CloseReason::Escape => DismissReason::Escape,
            ui::CloseReason::OutsidePress => DismissReason::OutsidePress,
            ui::CloseReason::SystemBack => DismissReason::SystemBack,
            ui::CloseReason::TriggerToggle => DismissReason::TriggerToggle,
            ui::CloseReason::Programmatic => DismissReason::Programmatic,
            ui::CloseReason::HostClosed => DismissReason::HostClosed,
        };
        let closed = matches!(stack.borrow_mut().request_close(reason), CloseResult::Closed(_));
        if closed { if let Some(app) = weak.upgrade() { app.set_showing(false); app.invoke_focus_opener(); } }
    });
    let weak = app.as_weak();
    app.on_archive(move || { if let Some(app) = weak.upgrade() { app.set_result("Project archived".into()); app.invoke_close(ui::CloseReason::Programmatic); } });
    app.run()
}

Cargo.toml and build.rs

Cargo.toml

[package]
name = "slint-kit-dialog-surface-example"
version = "0.1.0"
edition = "2024"
rust-version = "1.92"
license = "GPL-3.0-or-later"
publish = false

[dependencies]
slint-kit = "=0.3.0"
slint = { version = "=1.18.1", default-features = false, features = ["std", "compat-1-18", "backend-winit", "renderer-skia", "accessibility"] }

[build-dependencies]
slint-kit-build = "=0.3.0"

[workspace]

build.rs

fn main() { slint_kit_build::compile("ui/app.slint").expect("compile component example"); }

Files: Cargo.toml · build.rs · ui/app.slint · src/main.rs

Render it last in its window and supply DialogState from OverlayStack. With tab-policy: DialogTabPolicy.host (the default), connect focus-next(bool) to the registry of actual targets. With .native, let Slint traverse mounted controls and make every background target ineligible while the modal is open, using FieldAccess.disabled, disabled, or interactive: false as appropriate.

Only the topmost modal handles Escape and system Back (Key.Back), requesting CloseReason.escape and .system-back respectively. busy consumes these keys without requesting closure. In host mode it captures Tab/Shift+Tab; in native mode it leaves them to Slint traversal. Native policy does not automatically disable the background. A backdrop click requests CloseReason.outside-press when dismiss-on-backdrop is enabled.

View source ↗

Visual composition

The file below produces the screenshot. For controller-driven components, it shows the displayed state without supplying the Rust wiring. Create a project.

Show the screenshot source

// SPDX-License-Identifier: GPL-3.0-or-later
import { DialogTabPolicy, KitButton, KitDialogPanel, KitDialogSurface, KitTheme, KitThemes } from "@kit/kit.slint";

export component Example inherits Window {
    title: "KitDialogSurface example";
    preferred-width: 560px;
    preferred-height: 360px;
    max-width: 100000px;
    max-height: 100000px;
    background: root.theme.canvas;
    in-out property <KitTheme> theme: KitThemes.light;
    in-out property <string> status;
    KitDialogSurface { tab-policy: DialogTabPolicy.native; theme: root.theme; width: parent.width; height: parent.height; state: { open: true, topmost: true, busy: false }; KitDialogPanel { theme: root.theme; width: 420px; x: (parent.width - self.width) / 2; y: (parent.height - self.height) / 2; height: dialog-content.preferred-height; horizontal-stretch: 0; vertical-stretch: 0; accessible-name: "Archive project"; dialog-content := VerticalLayout { padding: 24px; spacing: 16px; alignment: start; Text { text: "Archive this project?"; color: root.theme.text-primary; font-size: 20px * root.theme.text-scale; font-weight: 600; wrap: word-wrap; vertical-stretch: 0; }Text { text: "You can restore it later from the archive."; color: root.theme.text-primary; font-size: 14px * root.theme.text-scale; wrap: word-wrap; vertical-stretch: 0; }KitButton { theme: root.theme; text: "Archive project"; activated => { root.status = "Action requested"; } }if root.status != "": Text { text: root.status; color: root.theme.text-secondary; font-size: 12px * root.theme.text-scale; wrap: word-wrap; vertical-stretch: 0; } } } }
}

Download this example

Public API

Inherits Rectangle.

Properties

Name	Type	Direction
`theme`	`KitTheme`	`in`
`state`	`DialogState`	`in`
`dismiss-on-backdrop`	`bool`	`in`
`tab-policy`	`DialogTabPolicy`	`in`

Types and variants

Type	Declaration
`enum CloseReason`	`escape, outside-press, system-back, trigger-toggle, programmatic, host-closed`
`struct DialogState`	`open: bool, topmost: bool, busy: bool`
`enum DialogTabPolicy`	`host, native`

Callbacks

dismiss(CloseReason)
focus-next(bool)