Struct WindowConfig 

pub struct WindowConfig {
    pub title: String,
    pub size: Size,
    pub resizable: bool,
    pub frame_interval: Duration,
    pub present: Present,
    pub fill_monitor: bool,
    pub position: Option<Point>,
    pub maximized: bool,
    pub app_id: Option<String>,
}

How the preview window is created.

Fields

title: String

Window title.

size: Size

Initial inner size in logical pixels.

Logical, not physical, so one number describes the same amount of desk on every machine: a panel designed at 800×480 covers 800×480 of a Pi’s framebuffer and the same apparent area on a 2× Retina display, where the surface it gets is 1600×960 physical pixels. Asking in physical pixels instead is how a window ends up a quarter of its intended size on a Mac.

The surface — and therefore every coordinate the application works in — stays physical. Scaling the content to match is the application’s job, and it is handed the factor at construction by run_with.

resizable: bool

Whether the user may resize the window.

frame_interval: Duration

Target frame interval. Defaults to 60 Hz.

The loop sleeps until the next deadline rather than spinning, so an idle UI costs close to nothing — which is the behaviour we actually care about on the target hardware.

present: Present

What draws the pixels. See Present.

fill_monitor: bool

Open at the size of the monitor instead of at size.

For an application that is going to cover the screen anyway — a kiosk, a panel, anything a window manager is about to fullscreen — where asking for a window the screen cannot hold is asking to be resized on the way up. Some window managers hand such a window a size, then the size it asked for, then the size again, and what reaches the glass afterwards is not always the last of them.

Falls back to size when no monitor can be identified, which is the case on some headless and remote displays.

position: Option<Point>

Where to put the window’s top-left, frame included, in the desktop’s physical pixels — or None to let the window manager place it.

The units are the ones InputEvent::SurfaceMoved reports in, so an application that keeps what it was last told and hands it back here opens where it closed, with nothing to convert on the way. Logical pixels are right for size and wrong for this: a desktop spanning a Retina display and a 1× one beside it has no single logical grid to name a point in.

A position no monitor covers is ignored rather than honoured — a display that has since been unplugged would otherwise open the window where nobody can reach it.

maximized: bool

Open maximised, whatever size says.

The size is still worth setting: it is what the window goes back to when the user un-maximises it.

app_id: Option<String>

The name the desktop knows this application by — Wayland’s app_id, X11’s WM_CLASS — or None for none.

It is what ties a window to the application’s desktop entry, so a launcher and a task bar show its name and icon, and what a window manager’s rules match. Give it the entry’s file name without .desktop: a window of squint.desktop says squint. Without one a Wayland compositor has nothing to go on, and every window rule and taskbar icon for the application is lost.

Set it on every window the application opens, the secondary ones included: each is a window of its own to the compositor. Ignored on macOS and Windows, which know an application by its bundle and its executable.

Trait Implementations

impl Clone for WindowConfig

fn clone(&self) -> WindowConfig

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for WindowConfig

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for WindowConfig

fn default() -> Self

Returns the “default value” for a type.