# GridColumnGroupDef

Fields, allowed values, and APIs that use GridColumnGroupDef.

Canonical: https://grid.syidax.com/docs/types/GridColumnGroupDef/

<a id="definition"></a>

## Type definition

A question mark (?) marks an optional field; readonly marks a value you should not change directly. A union (|) accepts one of the listed forms. Functions are callbacks that Grid invokes at the relevant point.

```typescript
export type GridColumnGroupDef<
  TData = GridData,
  TContext = unknown,
  TValue = unknown,
> = ColumnGroupDef<ColumnDef<TData, TValue, TContext>>;
```

<a id="used-by"></a>

## APIs using this type

- [columnDefs](https://grid.syidax.com/docs/options/columnDefs.md) — Defines column data fields, headings, sizes, visibility, and editing. Include column groups to create multi-level headers.

<a id="parents"></a>

## Contracts containing this type

- [DetailGridOptions](https://grid.syidax.com/docs/types/DetailGridOptions.md)
- [GridColumnDefinition](https://grid.syidax.com/docs/types/GridColumnDefinition.md)
- [GridColumnGroupRef](https://grid.syidax.com/docs/types/GridColumnGroupRef.md)

<a id="related"></a>

## Related types

- [GridData](https://grid.syidax.com/docs/types/GridData.md)
- [ColumnGroupDef](https://grid.syidax.com/docs/types/ColumnGroupDef.md)
- [ColumnDef](https://grid.syidax.com/docs/types/ColumnDef.md)