Button Switch

A pill-shaped toggle switch with role="switch". Clicking flips the bound checked state and slides the thumb. Apply to a <button> element whose first child is a <span> (used as the thumb).

Props

Prop	Type	Default	Description
`checked`	`ValueOrState<boolean>`	`false`	Toggle state — `true` = on.
`color`	`ValueOrState<ThemeColor>`	`"neutral"`	Theme color tone for the unchecked (off) track.
`accentColor`	`ValueOrState<ThemeColor>`	`"primary"`	Theme color tone for the checked (on) track.

Customization

Must see the source of patch at the bottom of each patch page to understand the structure then code it still code as html native element.

There are four levels of customization, in increasing order of effort:

Patch props. Each patch exposes a small, stable set of props—typically fewer than five. Lowest friction.
Context attributes. Use dataTone, dataSize, and dataDensity on a container to shift tone, size, or density for an entire subtree without touching individual elements.
Inline override. Native-wins merge strategy: any property set directly on the element overrides the patch value.
Create a variant. Clone a similar patch and edit it. Use this only when you need a reusable custom version.

Formulas

Unit - U = fontSize / 4 - convert final values with themeSpacing(n).

Size - n = intrinsic text lines, w = wrapping level, d = density factor:

height        = (n * 6 + 2 * d * w) * U
paddingBlock  = d * w * U
paddingInline = ceil(3 / w) * d * w * U
radius        = d * w * U

Base density d = 1.5:

U	w=0	w=1	w=2	w=3
height (`n = 1`)	6	9	12	15
paddingBlock	0	1.5	3	4.5
paddingInline	3	4.5	6	4.5
radius	0	1.5	3	4.5

Tone - K = N / 2 where N is the palette length. For N = 18, K = 9.

Role	Shift	n=0
Background	parent +/- n	0
Text	bg + K	6
Border	bg + K/2	3
Hover	bg + 2K/3	4
Selected / Focus	above +/- K/3	2-4

State shift range: K/3 <= delta <= 2K/3.

buttonSwitch

import { type PartialElement, toState, type ValueOrState } from "@domphy/core";
import {
  type ThemeColor,
  themeColor,
  themeSize,
  themeSpacing,
} from "@domphy/theme";
import { focusRing } from "../utils/focusRing.js";

/**
 * A pill-shaped toggle switch with `role="switch"`; clicking flips the bound
 * `checked` state and slides the thumb. Apply to a `<button>` element.
 *
 * @hostTag button
 * @param props.checked - Toggle state. Optional `ValueOrState<boolean>`, default false.
 * @param props.accentColor - Color tone when checked (on). Optional `ValueOrState<ThemeColor>`, default "primary".
 * @param props.color - Color tone when unchecked (off track). Optional `ValueOrState<ThemeColor>`, default "neutral".
 * @example { button: { span: null }, $: [buttonSwitch({ checked: true })] }
 */
function buttonSwitch(
  props: {
    checked?: ValueOrState<boolean>;
    accentColor?: ValueOrState<ThemeColor>;
    color?: ValueOrState<ThemeColor>;
  } = {},
): PartialElement {
  const { checked = false } = props;

  const check = toState(checked);
  const color = toState(props.color ?? "neutral", "color");
  const accentColor = toState(props.accentColor ?? "primary", "accentColor");

  return {
    _onSchedule: (node) => {
      if (node.tagName !== "button") {
        console.warn(`"buttonSwitch" primitive patch must use button tag`);
      }
    },
    role: "switch",
    ariaChecked: (listener) => check.get(listener),
    dataTone: "shift-2",
    onClick: () => check.set(!check.get()),
    style: {
      position: "relative",
      display: "inline-flex",
      alignItems: "center",
      fontSize: (listener) => themeSize(listener),
      border: "none",
      outlineWidth: "1px",
      outline: (listener) =>
        `1px solid ${themeColor(listener, "border", color.get(listener))}`,
      minWidth: themeSpacing(12),
      minHeight: themeSpacing(6),
      borderRadius: themeSpacing(999),
      paddingLeft: themeSpacing(7),
      paddingRight: themeSpacing(2),
      cursor: "pointer",
      transition:
        "padding-left 0.3s, padding-right 0.3s, background-color 140ms ease, box-shadow 140ms ease",
      backgroundColor: (listener) =>
        themeColor(listener, "inherit", color.get(listener)),
      color: (listener) => themeColor(listener, "text", color.get(listener)),
      "&:focus-visible": {
        boxShadow: (listener) => focusRing(listener, accentColor.get(listener)),
      },
      "& > :first-child": {
        content: '""',
        position: "absolute",
        display: "inline-flex",
        alignItems: "center",
        left: themeSpacing(0.5),
        top: "50%",
        transform: "translateY(-50%)",
        transition: "left 0.3s",
        width: themeSpacing(5),
        height: themeSpacing(5),
        borderRadius: themeSpacing(999),
        color: (listener) => themeColor(listener, "text"),
        backgroundColor: (listener) =>
          themeColor(listener, "decrease-2", color.get(listener)),
      },
      "&[aria-checked=true]": {
        backgroundColor: (listener) =>
          themeColor(listener, "increase-3", accentColor.get(listener)),
        outline: "none",
        color: (listener) => themeColor(listener, "decrease-2"),
        paddingLeft: themeSpacing(2),
        paddingRight: themeSpacing(7),
      },
      "&[aria-checked=true] > :first-child": {
        left: `calc(100% - ${themeSpacing(5.5)})`,
      },
      "&[disabled]": {
        opacity: 0.7,
        cursor: "not-allowed",
      },
    },
  };
}

export { buttonSwitch };

Button Switch#

Props#

Button Switch

Props