Stopwatch
Start becomes the running time (lit) and a Lap button beside it; each lap is a drop that leaves Lap and lands in the lap count. Pause dims the time and Lap flows into Reset, which folds everything back into Start.
Feel Every lap visibly goes somewhere.
Preview
Or let the agent fetch it: get_component("stopwatch") on the Echo MCP server.
Installation
First time? Run npx echo-ui-cli init once — it sets the project up, and add refuses to run before it.
At a glance
- Version
- 0.3.0
- Weight
- 6.2 KB · 38.9 KB with what it imports · 2.8 KB of CSS (minified and gzipped; React not counted)
- Needs
- hardware-button (Echo, brought with it), morph (Echo, brought with it), count-badge (Echo, brought with it), bud-off (Echo, brought with it)
- Keyboard
- Tab moves through the time cap, Lap and Reset; Enter or Space presses each.
- Reduced motion
- The states swap in place and laps count without a drop.
- Sound
- Each cap's own press, and a soft gulp as a lap lands (inside a SoundProvider).
Usage
import { Stopwatch } from "@/echo/stopwatch";
<Stopwatch />Composition
Stopwatch → Morph → HardwareButton ×2, CountBadge, useBudOff
Examples
Keep the laps
The component counts them; you keep the times.
<Stopwatch onLap={(n, ms) => setLaps((l: number[]) => [...l, ms])} />Accessibility
- The time cap says what pressing it does: "Pause stopwatch" / "Resume stopwatch".
- Each lap and its time, pausing and resetting are announced politely; the lap count is a status.
- The time is written straight into the cap, so nothing re-renders while it runs.
- Keyboard: Tab moves through the time cap, Lap and Reset; Enter or Space presses each.
Tested against WCAG 2.2 AA on every release:
axe— No axe violations, in the component's own gallery and on its page.keyboard— Every action is reachable and operable from the keyboard alone.focus-visible— Focus is visible on every focusable part, in normal and forced-colors mode.forced-colors— State stays visible when the look's colours are replaced by the system's.target-size— Every target's real hit area is at least 24×24px, at every density.reflow— Content reflows into 320px and survives a doubled text size.
Not covered: screen-reader: not yet verified by a person. Everything above is a machine check; a person has not yet driven this component with a screen reader.
Motion & sound
- Motion tokens
morphFeels.cell,morphFeels.mercury,morphFeels.cut- Reduced motion
- The states swap in place and laps count without a drop.
- Sound
- Each cap's own press, and a soft gulp as a lap lands (inside a SoundProvider).
Props
| Prop | Type | Default |
|---|---|---|
onLapCalled on every lap, with its number and the time, ms. | function | |
onResetCalled on reset, with the time it had reached, ms. | function | |
feelHow it moves: cell (the default) pinches evenly and each half swells round; mercury is short, quick and jiggles; cut is a clean cut, then the caps slide. | "cell" | "mercury" | "cut" | |
sizeHeight of its caps on the control scale: sm 32px, md 44px, lg 60px, as a HardwareButton of that size. Defaults to the nearest SizeProvider's size. | "sm" | "md" | "lg" | |
alignWhich edge stays put while the buttons change: center (the default), start or end. | "center" | "start" | "end" |
Anti-patterns
- Never use it to show elapsed time the user didn't start: that's a readout, not a control.
Changelog
- Every item needs
echo-ui-core0.3.0 (all components). The drawn device, readability past AA and the design tests live in core, and the components that use them are built against it, so each item now declaresecho-ui-core >=0.3.0 <0.4.0. Update core with the items:npm install echo-ui-core@^0.3.0(or your package manager's), thennpx echo-ui-cli update. An item whose files didn't change is the same code under a new version; the 0.2.0 files stay published. - Six more that change shape as you use them, all on
Morph.SaveButtonnarrows into its own progress while your save runs, widens into a lit "Saved" and flows back.Timeropens into durations; the others run into the one you pick, which drains as the time runs and rings.Stopwatchbuds a Lap button from Start, and every lap is a drop that lands in the lap count.VoiceNoterecords from the microphone: your voice swells the Stop button, and the take becomes a note that fills as it plays.AddToBagsends a drop from the button into the count beside it.useBudOffis that drop on its own, from any element into any other.Morphnow keeps a button's identity across states when it has the samedata-morphname, and draws filled caps as levels. - Comments only, no behaviour change. Comments in the component source used to cite documents, milestones and ticket numbers from Echo's own planning, none of which exist in your project. The citations are gone and the sentences around them stay. Where a comment was only a citation, it now says what it meant. Three development warnings (
HardwareButton'sengraved/captionchecks andStatusDot's missing-label check) also dropped the ticket code at the end of the message.echo-ui diffwill show changes in most items; none of them are to code. - An item's version is now a function of declared data, not of how the changelog is formatted. The version an item ships under is published once and never rewritten, and it used to be inferred from prose: a regex for a bolded "Breaking" run across the whole unreleased section, and attribution by "does a bullet mention this name in backticks". One breaking entry therefore moved every item that changed that cycle, and an entry explaining that "
MenuandSheetare unchanged here" filed itself as a change to Menu and Sheet — which it really had. - The agent brief says Echo has not shipped.
llms.txtand the MCP server's instructions led withnpx echo-ui-cli init, and that name on npm is a reserved stub with no executable — so a model following the brief wrote an install step that fails with npx's own error. The brief now opens with the caveat, and the docs carry it on every surface that shows a command. One switch (CLI_RELEASED) silences all of them at launch, and a test refuses to let one move without the others. Affectsall componentsonly in what the brief says about installing them; no item's props, CSS or rendered semantics change. - Echo's home is
echo-ui.com. The registry, the docs and the packages all move to it fromecho.nawwara.studio. Nothing was published under the old host, so noecho.jsonanywhere points at it and there is nothing to migrate — this is the last release where that is true. - Weights, line heights, letter-spacing, z-index, border widths and icon sizes come from the theme scales in
all components, with the old value as a fallback, so components keep working withecho-ui-core@0.0.1. Strays moved to the nearest step: most by under a pixel; HardwareButton icons are 14/16/20px (were 15/17/19). Stopwatch: Pause takes on every press in Safari (BUG-86). The running time is the cap's label and was rewritten every frame by replacing its text, so a press that began on the old text and ended on the new one was sometimes dropped. The time now changes in place.Stopwatch: a lap still in flight when you Reset no longer comes back (BUG-74). Its drop landed after the reset and put the old count back, so the next first lap briefly read "2 laps". To do it,budOff(…)fromuseBudOffnow returns a function that calls the drop off before it lands; ignoring it changes nothing.- Content now reflows into a 320px screen (400% zoom) and survives a doubled browser text size (WCAG 1.4.10, 1.4.4), across
all components.Select's 180px floor,NumberField's readout,SegmentedandStepsas flex items,EmptyState's grid columns, andAvatar's fixed-pixel disc all gave way;Panelcounts its padding inside a width you set (box-sizing: border-box), so a<Panel style={{ width: 220 }}>is now 220px wide overall rather than 260px.