busy

For an application that reloads rows it keeps on screen — a poll every minute, its own refresh button.

Type	boolean
Default	false
Live update (update())	Yes
Angular	the [busy] input
<dz-grid>	the busy attribute
Declared in	packages/dom/src/settings.ts

What it does

true: the grid says aria-busy="true" at once, and after 200 ms shows a thin bar under the header; once shown, the bar stays at least 400 ms, so a quick reload does not flicker. The rows stay readable and usable. Nothing is announced: a reader is not interrupted for a refresh. false ends it.

A server’s rows (source) do this by themselves when a request is made with rows kept on screen; busy is for the rows you give. The bar never shows with the « Loading… » overlay. Under motion: false or reduced motion, the bar is still; a part can draw your own instead (slots()).

Example

TypeScript

import { createGrid } from '@dzgrid/dom';
import { EN } from '@dzgrid/dom/locales/en';

type Train = { id: string; line: string; delay: number };

const grid = createGrid<Train>(document.getElementById('trains')!, {
  rows: [{ id: 't1', line: 'Coast line', delay: 4 }],
  columns: [{ id: 'line', header: 'Line' }, { id: 'delay', header: 'Delay (min)', type: 'number' }],
  getRowId: (t) => t.id,
  messages: EN,
});

setInterval(async () => {
  grid.update({ busy: true });
  const rows = (await (await fetch('/api/trains')).json()) as Train[];
  grid.update({ rows, busy: false });
}, 60_000);

Angular

import { Component, signal } from '@angular/core';
import { DzGrid, type DzgColumnOrGroup } from '@dzgrid/angular';
import { EN } from '@dzgrid/dom/locales/en';

type Train = { id: string; line: string; delay: number };

@Component({
  selector: 'app-trains',
  imports: [DzGrid],
  template: `<dz-grid [rows]="rows()" [columns]="columns" [getRowId]="rowId" [messages]="messages" [busy]="loading()" />`,
})
export class Trains {
  readonly rows = signal<Train[]>([{ id: 't1', line: 'Coast line', delay: 4 }]);
  readonly loading = signal(false);
  readonly columns: DzgColumnOrGroup<Train>[] = [{ id: 'line', header: 'Line' }, { id: 'delay', header: 'Delay (min)', type: 'number' }];
  readonly rowId = (t: Train) => t.id;
  readonly messages = EN;

  async reload(): Promise<void> {
    this.loading.set(true);
    this.rows.set((await (await fetch('/api/trains')).json()) as Train[]);
    this.loading.set(false);
  }
}

Web Component

<dz-grid busy></dz-grid>

import '@dzgrid/element/define';
import type { DzGridElement } from '@dzgrid/element';
import { EN } from '@dzgrid/dom/locales/en';

type Train = { id: string; line: string; delay: number };

const grid = document.querySelector<DzGridElement<Train>>('dz-grid')!;
grid.columns = [{ id: 'line', header: 'Line' }, { id: 'delay', header: 'Delay (min)', type: 'number' }];
grid.getRowId = (t) => t.id;
grid.messages = EN;
grid.rows = (await (await fetch('/api/trains')).json()) as Train[];
grid.removeAttribute('busy');

Live demo

busy: true — the rows stay, a thin bar under the header says they are being reloaded.

See also

• overlay — a message over the rows.
• Server data.