Module message_box 

MessageBox — QMessageBox-style alert dialog.

A higher-level surface built on top of ModalContainer for the classic “tell the user something and ask for a response” pattern: unsaved-changes prompts, error surfaces, confirmation dialogs, and informational notices. Mirrors QMessageBox (Qt), NSAlert (AppKit), and SwiftUI’s .alert(...) while staying inside Teksilo’s idioms — closure result handlers, Signal/Prop reactivity, Intent/Action/Shortcut routing for keyboard defaults, and AccessKit Role::AlertDialog accessibility.

Quick tour

use teksilo::prelude::*;
use teksilo::widgets::{MessageBox, MessageBoxButtons, StandardButton};

fn on_close(ctx: &mut EventContext) {
    MessageBox::question(lit!("Save changes?"))
        .text(lit!("You have unsaved changes in report.skrib."))
        .informative_text(lit!("Your changes will be lost if you don't save them."))
        .buttons(MessageBoxButtons::SaveDiscardCancel)
        .default_button(StandardButton::Save)
        .escape_button(StandardButton::Cancel)
        .on_result(|r, ctx| match r.button {
            StandardButton::Save => save_and_close(ctx),
            StandardButton::Discard => close(ctx),
            _ => {}
        })
        .present(ctx);
}

Severity

MessageBoxSeverity controls the icon drawn beside the title and its tint:

• Information — info glyph, status_info_fg tint.
• Question — question mark glyph, accent tint.
• Warning — exclamation triangle, status_warning_fg tint.
• Critical — X-mark circle, status_error_fg tint. Also disables click-outside dismissal (Qt convention).
• None — no icon, no tint.

Severity is conveyed through the icon + title + text. Per Teksilo’s Int UI baseline, buttons are never colored as “destructive”: destructive intent lives in the dialog’s severity and wording, not in the button. See crate::button for details.

Default & escape buttons

• default_button — activated by Enter (widget-scoped shortcut) and receives initial focus on open (via ModalRequest::focus_target plus Widget::initial_focus_hint). Styled with ButtonVariant::Filled.
• escape_button — activated by Escape. The fallback logic (for presets with no explicit escape_button) picks: explicit escape_button → first Reject-role button → Cancel → last button.

Each preset supplies a default: Ok for Ok and OkCancel, Save for SaveDiscardCancel, Retry for RetryIgnoreAbort, and No for YesNo and YesNoCancel.

The Yes/No default is the negative answer on purpose. An Ok/Cancel box confirms something the user just asked for, so Ok is the answer they meant. A Yes/No box asks a question they did not initiate, and it is overwhelmingly asked before something irreversible — “Delete this?”, “Discard your changes?”. Defaulting to Yes means Enter destroys, and Enter is what a keyboard user presses on a dialog they have not finished reading. Where the question is safe, default_button puts Yes back in one reviewable line; the reverse default cannot be reviewed, because there is nothing on the screen to review.

It matters more than it looks, because no platform announces which button is the default: Node::keyboard_shortcut appears in none of the three AccessKit adapters, so a screen-reader user discovers the default only by pressing Enter. Where focus lands is the whole contract.

Result reporting

MessageBox::on_result takes impl Fn(MessageBoxResult, &mut EventContext) + 'static. The callback fires exactly once — on button activation or Escape dismissal — then the modal is closed by the framework.

Accessibility

The widget exposes Role::AlertDialog (distinct from ModalContainer’s Role::Dialog), with set_modal(), set_live(Live::Assertive), set_name(title), and set_description(text + informative_text) so screen readers announce the dialog and its body on open.

Structs

MessageBox

A modal alert dialog that displays a severity icon, title, body text, and one or more buttons.

MessageBoxButton

A single button placement inside a MessageBox, including an optional per-instance label override. Callers usually build these via From<StandardButton> (StandardButton::Ok.into()), or construct them manually when Custom is needed.

MessageBoxResult

Report passed to MessageBox::on_result when the dialog closes.

Enums

ButtonRole

Semantic role of a message-box button. Used for fallback escape resolution (Reject wins when no explicit escape button is set). Teksilo deliberately does not render Destructive buttons with a red fill — the dialog’s severity icon and wording carry that signal. See crate::button for the framework-level rationale.

MessageBoxButtons

Pre-built button bundles covering the common MessageBox shapes. Custom combinations go through MessageBox::add_button or MessageBoxButtons::Custom.

MessageBoxSeverity

Alert severity level. Drives the icon glyph + tint shown beside the title, and (for Critical) whether click-outside dismiss is enabled.

StandardButton

The Qt-modeled catalog of standard buttons. Each variant resolves to a localized label, a semantic ButtonRole, and a stable intent-name string used internally for shortcut/action routing.

Traits

EventContextMessageBoxExt

Extension trait on EventContext for ergonomic MessageBox presentation. Mirrors ctx.present_modal(...) for the general case.