Column Sizing (Lit) Guide

Examples

Want to skip to the implementation? Check out these Lit examples:

Column Sizing

Lit Setup

import { LitElement, html } from 'lit'
import { customElement, state } from 'lit/decorators.js'
import { TableController, tableFeatures, columnSizingFeature } from '@tanstack/lit-table'

const features = tableFeatures({ columnSizingFeature })

@customElement('my-table')
class MyTable extends LitElement {
  @state()
  private data = defaultData

  private tableController = new TableController(this)

  protected render() {
    const table = this.tableController.table({
      features,
      columns,
      data: this.data,
    })

    return html`...`
  }
}

import { LitElement, html } from 'lit'
import { customElement, state } from 'lit/decorators.js'
import { TableController, tableFeatures, columnSizingFeature } from '@tanstack/lit-table'

const features = tableFeatures({ columnSizingFeature })

@customElement('my-table')
class MyTable extends LitElement {
  @state()
  private data = defaultData

  private tableController = new TableController(this)

  protected render() {
    const table = this.tableController.table({
      features,
      columns,
      data: this.data,
    })

    return html`...`
  }
}

The column sizing feature allows you to optionally specify the width of each column including min and max widths.

If you want users to dynamically change column widths by dragging column headers, see the Column Resizing Guide.

Column Widths

Columns by default are given the following measurement options:

export const defaultColumnSizing = {
  size: 150,
  minSize: 20,
  maxSize: Number.MAX_SAFE_INTEGER,
}

export const defaultColumnSizing = {
  size: 150,
  minSize: 20,
  maxSize: Number.MAX_SAFE_INTEGER,
}

These defaults can be overridden by both tableOptions.defaultColumn and individual column defs, in that order.

const features = tableFeatures({ columnSizingFeature })

const columns = [
  {
    accessorKey: 'col1',
    size: 270, //set column size for this column
  },
  //...
]

const table = this.tableController.table({
  features,
  defaultColumn: {
    size: 200, // starting column size
    minSize: 50, // enforced during column resizing
    maxSize: 500, // enforced during column resizing
  },
  //...
})

const features = tableFeatures({ columnSizingFeature })

const columns = [
  {
    accessorKey: 'col1',
    size: 270, //set column size for this column
  },
  //...
]

const table = this.tableController.table({
  features,
  defaultColumn: {
    size: 200, // starting column size
    minSize: 50, // enforced during column resizing
    maxSize: 500, // enforced during column resizing
  },
  //...
})

The column "sizes" are stored in the table state as numbers, and are usually interpreted as pixel unit values, but you can hook up these column sizing values to your css styles however you see fit.

As a headless utility, table logic for column sizing is really only a collection of states that you can apply to your own layouts how you see fit (our example above implements 2 styles of this logic). You can apply these width measurements in a variety of ways:

semantic table elements or any elements being displayed in a table css mode
div/span elements or any elements being displayed in a non-table css mode
- Block level elements with strict widths
- Absolutely positioned elements with strict widths
- Flexbox positioned elements with loose widths
- Grid positioned elements with loose widths
Really any layout mechanism that can interpolate cell widths into a table structure.

Each of these approaches has its own tradeoffs and limitations which are usually opinions held by a UI/component library or design system, luckily not you 😉.

Column Sizing APIs

Use the column and header APIs to read the calculated size and offsets for rendering. These values come from the columnSizing state and the column definition defaults.

column.getSize()
header.getSize()

column.getStart() // left offset in the current column flow
column.getStart('left')
column.getStart('center')
column.getStart('right')

column.getAfter() // right offset in the current column flow
column.getAfter('left')
column.getAfter('center')
column.getAfter('right')

column.resetSize()

column.getSize()
header.getSize()

column.getStart() // left offset in the current column flow
column.getStart('left')
column.getStart('center')
column.getStart('right')

column.getAfter() // right offset in the current column flow
column.getAfter('left')
column.getAfter('center')
column.getAfter('right')

column.resetSize()

The table instance also exposes total size helpers. These are useful when building scroll containers, split pinned-column tables, or CSS variables for column widths.

table.getTotalSize()
table.getLeftTotalSize()
table.getCenterTotalSize()
table.getRightTotalSize()

table.getTotalSize()
table.getLeftTotalSize()
table.getCenterTotalSize()
table.getRightTotalSize()

If you need to update sizing state directly, use table.setColumnSizing. Use table.resetColumnSizing to reset to initialState.columnSizing, or pass true to reset to the feature default.

table.setColumnSizing({
  firstName: 180,
  age: 80,
})

table.resetColumnSizing()
table.resetColumnSizing(true)

table.setColumnSizing({
  firstName: 180,
  age: 80,
})

table.resetColumnSizing()
table.resetColumnSizing(true)

Managing Column Sizing State

If you need to own the columnSizing state yourself (for example, to persist user-set column widths), the recommended v9 approach is an external atom passed to the table's atoms option. External atoms give you fine-grained subscriptions anywhere in your app, and other code can read or write the sizing state without going through the component that owns the table.

import { createAtom } from '@tanstack/store'
import type { ColumnSizingState } from '@tanstack/lit-table'

const features = tableFeatures({ columnSizingFeature })

// create a stable atom at module scope (or in a shared store module)
const columnSizingAtom = createAtom<ColumnSizingState>({})

const table = this.tableController.table({
  features,
  columns,
  data: this.data,
  atoms: {
    columnSizing: columnSizingAtom,
  },
})

// read columnSizingAtom.get() (or subscribe to columnSizingAtom) wherever you need the value

import { createAtom } from '@tanstack/store'
import type { ColumnSizingState } from '@tanstack/lit-table'

const features = tableFeatures({ columnSizingFeature })

// create a stable atom at module scope (or in a shared store module)
const columnSizingAtom = createAtom<ColumnSizingState>({})

const table = this.tableController.table({
  features,
  columns,
  data: this.data,
  atoms: {
    columnSizing: columnSizingAtom,
  },
})

// read columnSizingAtom.get() (or subscribe to columnSizingAtom) wherever you need the value

Alternatively, the v8-style state.columnSizing plus onColumnSizingChange pattern is still supported. It can be convenient for simple integrations or when migrating v8 code, but it is less fine-grained than external atoms. See the Table State Guide for a deeper comparison.

const features = tableFeatures({ columnSizingFeature })

@state()
private columnSizing: ColumnSizingState = {}

const table = this.tableController.table({
  features,
  columns,
  data: this.data,
  state: {
    columnSizing: this.columnSizing,
  },
  onColumnSizingChange: (updater) => {
    this.columnSizing = typeof updater === 'function' ? updater(this.columnSizing) : updater
  },
})

const features = tableFeatures({ columnSizingFeature })

@state()
private columnSizing: ColumnSizingState = {}

const table = this.tableController.table({
  features,
  columns,
  data: this.data,
  state: {
    columnSizing: this.columnSizing,
  },
  onColumnSizingChange: (updater) => {
    this.columnSizing = typeof updater === 'function' ? updater(this.columnSizing) : updater
  },
})

Column Sizing (Lit) Guide

Examples#

Lit Setup#