Struct QrCode 

pub struct QrCode { /* private fields */ }

A scannable QR code rendered as terminal cells.

Encodes data into a QR symbol and paints it with block glyphs. The common uses are handing something off to a phone: device-flow login URLs, WiFi credentials, TOTP enrollment secrets, or a link the user wants on another screen.

Sizing

Unlike every other widget, a QR symbol cannot reflow: its size is fixed by the payload length and error correction level. A symbol that gets clipped still looks like a QR code but will not scan, so check QrCode::size against the viewport and substitute a fallback when the terminal is too small:

let qr = QrCode::new("https://tui-lipan.dev");
let viewport = ctx.viewport();

match qr.size() {
    Some((w, h)) if w <= viewport.w && h <= viewport.h => qr.into(),
    _ => Text::new("https://tui-lipan.dev").into(),
}

Contrast

Scanners expect dark modules on a light background, so the default styling paints explicit Color::Black on Color::White rather than inheriting the terminal palette — a symbol rendered on a dark background is inverted and many readers will not decode it. Use QrCode::invert only when you know the target scanner handles it.

QrCode::new("https://tui-lipan.dev")
    .ecc(QrEcc::Quartile)
    .render(QrRender::Wide);

Implementations

impl QrCode

pub fn new(data: impl Into<Arc<str>>) -> Self

Create a QR code for the given payload.

pub fn ecc(self, ecc: QrEcc) -> Self

Set the error correction level.

pub fn render(self, render: QrRender) -> Self

Set how modules map onto terminal cells.

pub fn quiet_zone(self, modules: u16) -> Self

Set the light margin around the symbol, in modules.

Defaults to the spec-mandated 4. Scanners need this border to locate the symbol; dropping it below 4 trades reliability for space. Values are capped at 32.

pub fn dark(self, color: Color) -> Self

Set the color of dark modules.

pub fn light(self, color: Color) -> Self

Set the color of light modules and the quiet zone.

pub fn invert(self) -> Self

Swap the dark and light colors.

pub fn fallback(self, fallback: impl IntoElement) -> Self

Set the element rendered when the payload is too long to encode.

Without one, a payload that exceeds the largest QR version renders nothing.

pub fn module_count(&self) -> Option<u16>

Symbol width in modules, excluding the quiet zone.

Returns None when the payload is too long to encode.

pub fn size(&self) -> Option<(u16, u16)>

Cell footprint as (width, height), including the quiet zone.

Returns None when the payload is too long to encode. Compare this against the available space before rendering — a clipped symbol does not scan.

Trait Implementations

impl Clone for QrCode

fn clone(&self) -> QrCode

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl From<QrCode> for Element

fn from(qr: QrCode) -> Self

Converts to this type from the input type.