shoelace/src/components/qr-code/qr-code.ts

91 wiersze
2.3 KiB
TypeScript

import { html, LitElement } from 'lit';
import { customElement, property, query } from 'lit/decorators.js';
import { styleMap } from 'lit/directives/style-map.js';
import QrCreator from 'qr-creator';
import { watch } from '~/internal/watch';
import styles from './qr-code.styles';
/**
* @since 2.0
* @status stable
*
* @csspart base - The component's internal wrapper.
*/
@customElement('sl-qr-code')
export default class SlQrCode extends LitElement {
static styles = styles;
@query('canvas') canvas: HTMLElement;
/** The QR code's value. */
@property() value = '';
/** The label used when screen readers announce the code. If unspecified, the value will be used. */
@property() label = '';
/** The size of the code's overall square in pixels. */
@property({ type: Number }) size = 128;
/** The fill color. This can be any valid CSS color, but not a CSS custom property. */
@property() fill = '#000';
/** The background color. This can be any valid CSS color or `transparent`, but not a CSS custom property. */
@property() background = '#fff';
/** The edge radius of each module. Must be between 0 and 0.5. */
@property({ type: Number }) radius = 0;
/** The level of error correction to use. */
@property({ attribute: 'error-correction' }) errorCorrection: 'L' | 'M' | 'Q' | 'H' = 'H';
firstUpdated() {
this.generate();
}
@watch('background')
@watch('errorCorrection')
@watch('fill')
@watch('radius')
@watch('size')
@watch('value')
generate() {
if (!this.hasUpdated) {
return;
}
QrCreator.render(
{
text: this.value,
radius: this.radius,
ecLevel: this.errorCorrection,
fill: this.fill,
background: this.background === 'transparent' ? null : this.background,
// We draw the canvas larger and scale its container down to avoid blurring on high-density displays
size: this.size * 2
},
this.canvas
);
}
render() {
return html`
<div
class="qr-code"
part="base"
style=${styleMap({
width: `${this.size}px`,
height: `${this.size}px`
})}
>
<canvas role="img" aria-label=${this.label.length > 0 ? this.label : this.value}></canvas>
</div>
`;
}
}
declare global {
interface HTMLElementTagNameMap {
'sl-qr-code': SlQrCode;
}
}