Tuner
A number picked the way a radio is tuned: a scale printed on the screen slides under a fixed, lit needle, and a seven-segment reading follows it. Drag it with your hand, flick it and it coasts onto a step, and every tick that passes the needle clicks. It fits a big range into a small width, since the range scrolls instead of being squeezed. A slider for assistive tech, with every slider key.
Feel A radio dial: the scale moves with your finger, coasts when you let it go, and clicks into each step as it passes the needle.
Preview
Or let the agent fetch it: get_component("tuner") 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
- 4.1 KB · 31.6 KB with what it imports · 1.8 KB of CSS (minified and gzipped; React not counted)
- Needs
- segment-display (Echo, brought with it), scope (Echo, brought with it)
- Keyboard
- Arrow keys step, Page Up/Down move one numbered tick, Home and End go to the ends.
- Reduced motion
- The scale jumps to each value: no coasting after a flick, no travel after a key.
- Sound
- A short click at every step that passes the needle, inside a SoundProvider.
Usage
import { Tuner } from "@/echo/tuner";
<Tuner label="Weight" unit="kg" min={30} max={150} step={0.5} defaultValue={72.5} />Composition
Tuner SegmentDisplay (the reading) the scale (a role="slider" element) and its needle
Examples
Weight
Half-kilo steps; the reading keeps its width with a dim leading zero.
<Tuner label="Weight" unit="kg" min={30} max={150} step={0.5} defaultValue={72.5} />A radio
Tenths of a megahertz, numbered every whole one.
<Tuner label="Frequency" unit="MHz" min={87.5} max={108} step={0.1} defaultValue={88.5} />Controlled
The reading lands in your state a step at a time as the scale moves.
<Tuner label="Tip" unit="%" min={0} max={30} value={tip} onValueChange={setTip} />Accessibility
role="slider"named bylabel, witharia-valuenow, min, max, and the reading with its unit asaria-valuetext(orformatValue's).- Arrow keys step, Page Up/Down move one numbered tick, Home and End go to the ends.
- An up-and-down wheel only turns it once it has focus, so scrolling a page never catches on it; a sideways swipe turns it at any time.
- Dragging and flicking are pointer extras: everything they do, the keys do.
- The reading above the scale is drawing; the slider says the value.
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
springs- Reduced motion
- The scale jumps to each value: no coasting after a flick, no travel after a key.
- Sound
- A short click at every step that passes the needle, inside a SoundProvider.
Props
| Prop | Type | Default |
|---|---|---|
idThe element's id, so a <label for> or an aria-describedby can reach it. | string | |
nameThe field's name in a form submission, and the key react-hook-form registers. | string | |
disabled | boolean | false |
required | boolean | |
readOnly | boolean | |
autoFocusFocus this control when it mounts. One per page, at most. | boolean | |
onBlurFired on focus loss. react-hook-form validates onTouched and onBlur with it. | function | |
onFocusFired when the control takes focus. | function | |
onKeyDownKeyboard handling you own — Enter to send, Escape to clear. Runs before Echo's. | function | |
label requiredWhat it sets: the machine label over the reading, and the accessible name. | string | |
valueControlled value. | number | |
defaultValueUncontrolled starting value; defaults to min. | number | |
onValueChangeCalled with each step the reading lands on. | function | |
min | number | 0 |
max | number | 100 |
stepA range that isn't a whole number of steps ends on the last step inside it: 0 to 10 by 4 stops at 8. | number | 1 |
unitEngraved after the reading, and said with it: "kg", "MHz". | string | |
labelEveryThe numbered ticks, in value units. Default: the nicest number that's at least eight steps. | number | |
formatValueHow the value is said to assistive technology. Default: the reading and its unit ("72.5 kg"). | function | |
screenemissive: a dark screen that glows. reflective: paper-coloured glass, printed in ink, like a pocket calculator's. | "emissive" | "reflective" | "emissive" |
Anti-patterns
- Never use a Tuner for a choice between a few values: that's a Segmented or a RadioGroup.
- Never leave out unit when the number has one: "72.5" means nothing, "72.5 kg" does.
- Never make the step so fine that one value is hard to land on by hand; a tenth of the thing people care about is usually enough.
Changelog
- The drawn device (
echo-ui-core,echo-ui-cli, every component that draws its own material). A seed's newrendersetting ismolded(Echo as it has always been: plastic lit by one key light) ordrawn: the same parts drawn in the ink, the way a spec sheet draws a key. Every part is outlined at one weight (--echo-line,--echo-line-width), hollow on the body; a raised part stands on a hard ink edge as deep as it rises and travels down it when pressed; a recess is an outline drawn inside; something floating stands on a deeper edge. There's no light, so no gloss, no soft shadow and no glow: what a molded device lights (an LED, the rail, a readout, the focus ring, a fader's knob, a radio's pip) is solid ink, and a low-emphasis action is its label underlined. In black and white (the accent the ink) "on" is solid ink and what's drawn on it inverts: a switch's thumb turns paper, a fader's knob is knocked out with a paper ring. The primary key is the paper key that stands highest, on an ink edge twice as deep as a neutral one's, the way a spec sheet draws its CTA. The accent stays the seed's own colour as a flat fill for what's on (a chosen segment, a checked box, a slider's travel, a switch that's on), so an acid highlighter is acid, not the olive a molded device holds it to; what's drawn on it is the ink, or the body when the accent is too deep for the ink. Pressing, travel, sound, what each material is for and every contrast guarantee are unchanged.npx echo-ui-cli style set render drawnturns it on; a style sets it in its seed; the published style and config schemas describe it, andDESIGN.mdsays how a drawn device builds. A molded device renders exactly as before: every line is 0px wide there, and each drawn value a component reads (--echo-drawn-fill,-on-fill,-ink,-rule,-glass,-hollow,-decoration) isinitial, so it falls back to what the component always drew. HardwareButton's bed is the one new hand-tuned shadow: a drawn key stands on its own edge instead of being drawn in a recess. - 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. - The light device (
echo-ui-core,echo-ui-cli). Echo can be light: a pale chassis makes a device molded in light plastic, like a white calculator or a cream radio, and a dark one makes the device Echo has always been. There's no setting and no mode to switch; the chassis decides (devicePolarity, andvalues.polarityon the theme). On a light device the page is light: its ground, the well, is the body barely set in. Caps get their own ladder, a step lighter than the body with a lit rim that stops short of white, so they keep their bevel; undersides and seams are shaded darker; dim text moves toward the ground by the same step as on a dark device, and reads about 6:1 on it. Screens are paper glass printed in ink, because a glow on a pale body is a smudge. What's lit (an LED, the current rail) is still the accent, held to 3:1 on every ground, so on is brighter than off; the text it prints (a readout, a count, a current tab) and the focus ring are the accent's ink, a step deeper and held to AA, in the newaccent-inkrole. The primary cap is the same cap as a dark device's, the accent with a light label: its label is the newprimary-cap-inkrole, and progress cells, loader dots and a meter's fill, the same plastic, read 3:1 on the page. A neutral cap or a slider that fills with it under its own dark label fills with the newpour-*roles, the accent's pale stops. Shadows are drawn at half their weight, in a deep colour of the body's own hue (--echo-cast-ink) instead of black. Every guarantee holds as it does on a dark device, and the contrast sweep now runs on light bodies too. A dark seed makes exactly the theme it did before, and the new roles equal the ones they stand for there. The components that mixed a recess toward black, painted paper in the text colour or lit a pillow of light with it read the theme's new--echo-shade-ink,--echo-paper-stockand--echo-paper-inkinstead, with the old value as the fallback, and a reflective screen reads--echo-screen-*; the components that print a lit label read--echo-primary-cap-inkand--echo-accent-inkthe same way; every rail is drawn in the glow, and every focus ring, theringrecipes included, in the ink.style usewears a light style now, andstyle checksays which device a style makes. A dark screen tint on a light body is still refused: one text colour can't serve both, and the theme says so. Tuner: a number picked the way a radio is tuned. A scale printed on the screen slides under a fixed, lit needle and aSegmentDisplayreading follows it. Drag it with your hand, flick it and it coasts onto a step; every tick that passes the needle clicks, and past either end it gives a little and springs back. It fits a big range into a small width: weight, height, a tip, a zoom level, a frequency. A slider for assistive tech, with the reading and itsunitin words and every slider key; the wheel only turns it once it has focus.- Reflective screens.
screen="reflective"gives a screen the paper glass of a pocket calculator, printed in ink: digits, labels and ghost segments in the chassis colour, nothing glowing. The ink is held to AA on the glass under every theme. OnSegmentDisplay,Tuner,Keypad,DateTile,NowPlaying,AnnunciatorandDescriptionList's screen. - Components whose shadow is a recipe read it by name. 71 shadows in 54 items now say
var(--echo-shadow-<name>, <the same shadow>), so they look exactly as they did (every docs page was compared before and after) and follow a theme's recipes. Scope declares the recipes that read the accent again, so a Scope's own colour still reaches its focus rings and glows, and reflective screens do the same for theirs. Shadows that move with their part (a cap's drop as it's pressed) stay in the component. - 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). - A light device's recesses keep the body's hue in Chromium (
echo-ui-core, BUG-166). Chromium drops the hue of a colour under 0.02 chroma when it mixes in oklch, and draws the mix at hue 0, a rose. A light device's plastic is that grey, so on a lilac body every field, track and rail was pink. A mix made only of greys is made in oklab now, which has no hue to lose; a mix with an accent in it stays in oklch. On a dark device nothing you can see changes. - 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.