Module window 

Windows as data: what a frame declares about the OS windows it wants, and the commands a frame driver applies to the real ones.

You meet this module in three places. WindowConfig is what Ui::window / Core::declare_window take to say that a named window exists this frame; NodeSpec::window_drag and NodeSpec::window_button make a node part of the window chrome; and a driver drains the resulting WindowCommands with Core::take_window_commands and applies them. The core never touches a window itself, so a headless driver simply never drains. Facts about the host window flow back in through WindowEnv on Env.

use kui_core::{Rect, WindowCommand, WindowConfig, WindowId, WindowKind};

// A second window, opened on the first frame that declares it.
let palette = WindowConfig::sized(320.0, 480.0);
assert_eq!(palette.kind, WindowKind::Normal);

// A dropdown surface anchored to a field's rect; it does not take focus.
let field = Rect::new(20.0, 40.0, 200.0, 24.0);
let menu = WindowConfig::popup(field, 200.0, 160.0);
assert_eq!(menu.kind, WindowKind::Popup);
assert!(!menu.activates);

// What a driver does with the commands it drains.
fn apply(cmd: WindowCommand) {
    match cmd {
        WindowCommand::Open { id, config, .. } => println!("open {id:?} at {:?}", config.size),
        WindowCommand::Close(WindowId::MAIN) => println!("exit"),
        WindowCommand::Close(id) => println!("close {id:?}"),
        WindowCommand::SetSize { window, size } => println!("resize {window:?} to {size:?}"),
        other => println!("{}", other.kind_name()),
    }
}
apply(WindowCommand::Close(WindowId::MAIN));

Structs

WindowConfig

What a frame says about a window it declares (Ui::window, Core::declare_window). Plain data, no title and no callbacks, so a WindowCommand stays Copy and two declarations of one name compare by value.

WindowEnv

What the host knows about its window, pushed into Env by the frame driver. Views (e.g. widgets::titlebar) read this to adapt: reserve space for native controls, pick the maximize/restore glyph, or render nothing at all under native decorations.

WindowId

Which OS window something belongs to: an opaque integer the core assigns when it opens a window, not a handle an app builds. WindowId::MAIN is 0, the window the launcher opens, which is always live. Apps name windows with a stable string (Core::declare_window); the id is how the driver and UiEvent::window refer to the surface that string opened.

Enums

Backdrop

What shows through a window where its frame paints nothing, or paints with alpha (backlog F126): named for the effect, not for where an app uses it. The app decides which regions show it — a sidebar, a toolbar — by painting them with alpha and the rest opaque; kui knows nothing of sidebars.

DismissReason

Why a window was asked to go away (Core::dismiss_window): the same two reasons a modal node has, one level up.

WindowButton

WindowCommand

A window-level intent for the frame driver, drained with Core::take_window_commands after each input dispatch and each frame. Three things produce one: input on a chrome node, the diff of the declared window set, and an app asking directly (Core::set_window_size, Core::focus_window, Core::push_window_command). A headless driver never drains.

WindowKind

What kind of OS surface a declared window is.

WindowRole

Role a node plays in window chrome (set via NodeSpec::window_drag / NodeSpec::window_button). Chrome nodes never emit UiEvents — their interactions become WindowCommands for the driver instead.