HierarchyPlugin

Since v3.9.0

Hierarchy Plugin for tbw-grid

Builds one hierarchical row model from every attached structure contributor — TreePlugin discovers child rows, GroupingRowsPlugin groups sibling lists — and announces each row’s position with the WAI-ARIA treegrid pattern (aria-level / aria-setsize / aria-posinset).

Contributors know nothing about each other, so they compose: a grid with both Tree and GroupingRows groups the children of every tree level.

You never need to add this plugin yourself — TreePlugin and GroupingRowsPlugin declare it as a dependency and the grid attaches it automatically. It has no configuration.

Example

Group the children of every tree node

import { TreePlugin } from '@toolbox-web/grid/plugins/tree';
import { GroupingRowsPlugin } from '@toolbox-web/grid/plugins/grouping-rows';

grid.gridConfig = {
  plugins: [
    new TreePlugin({ childrenField: 'children' }),
    new GroupingRowsPlugin({
      // Leave the root level ungrouped, group every child level by kind
      groupOn: (row, { depth }) => (depth > 0 ? row.kind : null),
    }),
  ],
};

Extends BaseGridPlugin

Inherited methods like attach(), detach(), afterRender(), etc. are documented in the base class.

Methods

process() v3.9.0+

Build the row model for a contributor’s processRows hook.

Every contributor forwards its hook here; only the one that runs last in the processRows pipeline builds the model (for all contributors at once) — the earlier ones pass their rows through untouched.

process(rows: readonly unknown[], caller: HierarchyContributor): unknown[]

Parameters

Name	Type	Description
rows	readonly unknown[]
caller	HierarchyContributor

Example

override processRows(rows: readonly unknown[]): unknown[] {
  return this.grid.getPluginByName('hierarchy')?.process(rows, this) ?? [...rows];
}

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getRowMeta() v3.9.0+

Hierarchy position of a row in the current row model, or undefined when the row is not rendered (e.g. collapsed under a parent).

getRowMeta(row: unknown): HierarchyRowMeta | undefined

Parameters

Name	Type	Description
row	unknown

Example

const meta = grid.getPluginByName('hierarchy')?.getRowMeta(grid.rows[0]);
console.log(meta?.level, meta?.posInSet, meta?.setSize);

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