# GroupHeaderRenderParams

> _Since v0.1.1_

Parameters passed to the groupHeaderRenderer
and per-group renderer callbacks.

#### Example

```ts
groupHeaderRenderer: (params) => {
  const icons = { personal: '👤', work: '💼' };
  return `${icons[params.id] ?? '📁'} <strong>${params.label}</strong>`;
}
```

## Properties

| Property | Type | Description |
| -------- | ---- | ----------- |
| `id` | <code>string</code> | The group ID (e.g. `'personal'`, `'work'`). |
| `label` | <code>string</code> | The group display label. Falls back to id if no label was provided. |
| `columns` | <code><a href="/grid/api/core/interfaces/columnconfig/">ColumnConfig</a>&lt;any&gt;[]</code> | The column configurations belonging to this group. |
| `firstIndex` | <code>number</code> | Zero-based index of the first column in this group within the visible columns array. |
| `isImplicit` | <code>boolean</code> | `true` for auto-generated groups that cover ungrouped columns. Always `false` when called from the renderer (implicit groups are skipped). |