Row Grouping

RowGroupManager organizes rows into parent-child groups with expand/collapse toggling and aggregate computation. Groups can be nested (multi-level) and each level can have independent expand/collapse state.

Live Demo

Click group headers to expand/collapse. Sales and Revenue show sum aggregates for each group.

3 groups: Electronics (3 items), Clothing (4 items), Food (2 items)

View source code

import { useRef, useEffect, useState } from 'react';
import { WitTable } from '@witqq/spreadsheet-react';
import type { WitTableRef } from '@witqq/spreadsheet-react';
import type { ColumnDef } from '@witqq/spreadsheet';
import { DemoWrapper } from './DemoWrapper';
import { useSiteTheme } from './useSiteTheme';

const columns: ColumnDef[] = [
  { key: 'category', title: 'Category', width: 180 },
  { key: 'product', title: 'Product', width: 160 },
  { key: 'sales', title: 'Sales', width: 100, type: 'number' },
  { key: 'revenue', title: 'Revenue', width: 120, type: 'number' },
];

const data = [
  { category: 'Electronics', product: '', sales: 0, revenue: 0 },
  { category: '', product: 'Laptop', sales: 150, revenue: 225000 },
  { category: '', product: 'Phone', sales: 320, revenue: 256000 },
  { category: '', product: 'Tablet', sales: 80, revenue: 48000 },
  { category: 'Clothing', product: '', sales: 0, revenue: 0 },
  { category: '', product: 'Shirt', sales: 500, revenue: 25000 },
  { category: '', product: 'Pants', sales: 300, revenue: 24000 },
  { category: '', product: 'Jacket', sales: 120, revenue: 36000 },
  { category: '', product: 'Shoes', sales: 200, revenue: 30000 },
  { category: 'Food', product: '', sales: 0, revenue: 0 },
  { category: '', product: 'Bread', sales: 1000, revenue: 5000 },
  { category: '', product: 'Milk', sales: 800, revenue: 3200 },
];

export function RowGroupingDemo() {
  const { witTheme } = useSiteTheme();
  const tableRef = useRef<WitTableRef>(null);
  const [info, setInfo] = useState('3 groups: Electronics (3 items), Clothing (4 items), Food (2 items)');

  useEffect(() => {
    const engine = tableRef.current?.getInstance();
    if (!engine) return;
    const rgm = engine.getRowGroupManager();

    rgm.setCellStore(engine.getCellStore());
    rgm.setGroups([
      { headerRow: 0, childRows: [1, 2, 3], expanded: true },
      { headerRow: 4, childRows: [5, 6, 7, 8], expanded: true },
      { headerRow: 9, childRows: [10, 11], expanded: true },
    ]);
    rgm.setAggregates([
      { col: 2, fn: 'sum' },
      { col: 3, fn: 'sum' },
    ]);

    engine.requestRender();
  }, []);

  const handleToggleAll = (expand: boolean) => {
    const engine = tableRef.current?.getInstance();
    if (!engine) return;
    const rgm = engine.getRowGroupManager();
    if (expand) rgm.expandAll(); else rgm.collapseAll();
    engine.requestRender();
    setInfo(expand ? 'All groups expanded' : 'All groups collapsed');
  };

  return (
    <DemoWrapper title="Live Demo" description="Click group headers to expand/collapse. Sales and Revenue show sum aggregates for each group." height={440}>
      <div style={{ display: 'flex', flexDirection: 'column', height: '100%' }}>
        <div style={{ padding: '0.5rem 0.75rem', borderBottom: '1px solid #e2e8f0', flexShrink: 0, display: 'flex', gap: '0.5rem', alignItems: 'center' }}>
          <button onClick={() => handleToggleAll(true)} style={{ padding: '4px 12px', cursor: 'pointer' }}>➕ Expand All</button>
          <button onClick={() => handleToggleAll(false)} style={{ padding: '4px 12px', cursor: 'pointer' }}>➖ Collapse All</button>
          <span style={{ fontSize: '0.8rem', color: '#64748b' }}>{info}</span>
        </div>
        <div style={{ flex: 1 }}>
          <WitTable
            theme={witTheme}
            ref={tableRef}
            columns={columns}
            data={data}
            showRowNumbers
            style={{ width: '100%', height: '100%' }}
          />
        </div>
      </div>
    </DemoWrapper>
  );
}

Configuring Groups

import { useRef, useEffect } from 'react';
import { WitTable, WitTableRef } from '@witqq/spreadsheet-react';

function App() {
  const ref = useRef<WitTableRef>(null);

  useEffect(() => {
    const engine = ref.current?.getInstance();
    if (!engine) return;
    const rgm = engine.getRowGroupManager();

    rgm.setCellStore(engine.getCellStore());
    rgm.setGroups([
      { headerRow: 0, childRows: [1, 2, 3], expanded: true },
      { headerRow: 4, childRows: [5, 6], expanded: false },
    ]);
    rgm.setAggregates([
      { col: 2, fn: 'sum' },
    ]);
    engine.requestRender();
  }, []);

  return <WitTable ref={ref} columns={columns} data={data} />;
}

Aggregate Functions

Function	Description
`sum`	Sum of leaf row values
`count`	Number of leaf rows
`average`	Average of leaf row values
`min`	Minimum value
`max`	Maximum value

API Reference

RowGroupManager

Method	Signature	Description
`setGroups`	`(groups: RowGroupDef[]) => void`	Define all groups
`toggleGroup`	`(headerRow: number) => void`	Toggle expand/collapse
`expandAll`	`() => void`	Expand all groups
`collapseAll`	`() => void`	Collapse all groups
`setAggregates`	`(agg: ColumnAggregate[]) => void`	Configure aggregates
`computeAggregates`	`(headerRow: number) => AggregateResult[]`	Compute for group