A simple thermostat UI with a switchable scale. Operable by dragging in a circle or using the arrow keys.
A Pen by Jon Kantner on CodePen.
<div class="t"> | |
<div class="t__inner"> | |
<div class="t__value"> | |
<span class="t__digit" data-temp>-</span><span class="t__digit" data-temp>-</span><span class="t__degree">°</span> | |
</div> | |
<button class="t__drag" type="button" data-drag> | |
<span class="t__sr" data-temp-sr>--</span> | |
</button> | |
<svg class="t__arrows" width="256px" height="256px" viewBox="0 0 256 256"> | |
<g fill="none" stroke="currentColor" stroke-width="4" stroke-linecap="round" stroke-linejoin="round" opacity="0.2"> | |
<polyline points="227.893 117.393 238.499 128 249.107 117.392"/> | |
<polyline points="5.393 117.393 16 128 26.608 117.392"/> | |
<path d="M16,128a111.25,111.25,0,0,1,222.5,0"/> | |
</g> | |
</svg> | |
<span class="t__units"> | |
<button class="t__unit" type="button" value="f" aria-label="Fahrenheit" data-scale>F</button> | |
<button class="t__unit" type="button" value="c" aria-label="Celsius" data-scale>C</button> | |
</span> | |
</div> | |
</div> |
A simple thermostat UI with a switchable scale. Operable by dragging in a circle or using the arrow keys.
A Pen by Jon Kantner on CodePen.
window.addEventListener("DOMContentLoaded",() => { | |
const thermostat = new Thermostat(".t"); | |
}); | |
class Thermostat { | |
constructor(qs) { | |
this.el = document.querySelector(qs); | |
this.temp = 60; | |
this.scale = "f"; | |
this.min = { | |
f: 60, | |
c: 16, | |
hue: 10, | |
angle: 0 | |
}; | |
this.max = { | |
f: 90, | |
c: 32, | |
hue: 50, | |
angle: 359 | |
}; | |
this.init(); | |
} | |
init() { | |
const dataAttr = "[data-drag]"; | |
const dragEl = this.el?.querySelector(dataAttr); | |
const draggingClass = "t__drag--dragging"; | |
dragEl?.addEventListener("keydown",this.changeTemp.bind(this)); | |
this.el?.addEventListener("click",this.changeScale.bind(this)); | |
Draggable.create(dataAttr,{ | |
type: "rotation", | |
bounds: { | |
minRotation: this.min.angle, | |
maxRotation: this.max.angle | |
}, | |
onDrag: () => { | |
this.temp = this.tempFromDrag(); | |
this.updateDisplay(); | |
dragEl.classList.add(draggingClass); | |
}, | |
onDragEnd: () => { | |
dragEl.classList.remove(draggingClass); | |
} | |
}); | |
this.updateDisplay(); | |
} | |
changeTemp(e) { | |
const { key } = e; | |
const step = 1; | |
// value change | |
if (key === "ArrowUp" || key === "ArrowRight") | |
this.temp += step; | |
else if (key === "ArrowDown" || key === "ArrowLeft") | |
this.temp -= step; | |
// keep within bounds | |
if (this.temp < this.min[this.scale]) | |
this.temp = this.min[this.scale]; | |
else if (this.temp > this.max[this.scale]) | |
this.temp = this.max[this.scale]; | |
this.updateDisplay(); | |
} | |
changeScale(e) { | |
if (e.target.hasAttribute("data-scale") && this.scale !== e.target.value) { | |
this.scale = e.target.value; | |
const rawTemp = this.scale === "f" ? this.CToF(this.temp) : this.FToC(this.temp); | |
this.temp = Math.round(rawTemp); | |
this.updateDisplay(); | |
} | |
} | |
setAriaPressed() { | |
const scale = this.el?.querySelectorAll("[data-scale]"); | |
if (scale) { | |
Array.from(scale).forEach(s => { | |
s.setAttribute("aria-pressed",s.value === this.scale); | |
}); | |
} | |
} | |
setDigits() { | |
// screen reader value | |
const sr = this.el?.querySelector("[data-temp-sr]"); | |
if (sr) | |
sr.textContent = `${this.temp}°${this.scale.toUpperCase()}`; | |
// displayed value | |
const tempDigits = this.el?.querySelectorAll("[data-temp]"); | |
if (tempDigits) { | |
const digitString = String(this.temp).split("").reverse(); | |
Array.from(tempDigits).reverse().forEach((digit,i) => { | |
digit.textContent = digitString[i]; | |
}) | |
} | |
} | |
setTone() { | |
const minHue = this.min.hue; | |
const maxHue = this.max.hue; | |
const temp = this.temp; | |
const minTemp = this.min[this.scale]; | |
const maxTemp = this.max[this.scale]; | |
const hueDiff = maxHue - minHue; | |
const relativeHue = hueDiff * ((temp - minTemp) / (maxTemp - minTemp)); | |
const hue = Math.round(maxHue - relativeHue); | |
this.el?.style.setProperty("--temp-hue",hue); | |
} | |
CToF(c) { | |
return c * (9 / 5) + 32; | |
} | |
FToC(f) { | |
return (f - 32) * (5 / 9); | |
} | |
angleFromMatrix(transVal) { | |
const matrixVal = transVal.split("(")[1].split(")")[0].split(","); | |
const [cos1,sin] = matrixVal.slice(0,2); | |
let angle = Math.round(Math.atan2(sin,cos1) * (180 / Math.PI)); | |
if (angle < 0) | |
angle += 360; | |
return angle; | |
} | |
tempFromDrag() { | |
const drag = this.el.querySelector(".t__drag") | |
if (drag) { | |
const dragCS = window.getComputedStyle(drag); | |
const trans = dragCS.getPropertyValue("transform"); | |
const dragAngle = this.angleFromMatrix(trans); | |
const relAngle = dragAngle - this.min.angle; | |
const angleFrac = relAngle / (this.max.angle - this.min.angle); | |
const tempRange = this.max[this.scale] - this.min[this.scale]; | |
const result = angleFrac * tempRange + this.min[this.scale]; | |
return Math.round(result); | |
} | |
} | |
updateDisplay() { | |
this.setDigits(); | |
this.setAriaPressed(); | |
this.setTone(); | |
} | |
} |
<script src="https://unpkg.co/gsap@3/dist/gsap.min.js"></script> | |
<script src="https://unpkg.com/gsap@3/dist/Draggable.min.js"></script> |
* { | |
border: 0; | |
box-sizing: border-box; | |
margin: 0; | |
padding: 0; | |
} | |
:root { | |
--hue: 223; | |
--bg: hsl(var(--hue),10%,70%); | |
--fg: hsl(var(--hue),10%,10%); | |
--primary: hsl(var(--hue),90%,55%); | |
--trans-dur: 0.3s; | |
font-size: calc(16px + (20 - 16) * (100vw - 320px) / (1280 - 320)); | |
} | |
body, | |
button { | |
font: 1em/1.5 Montserrat, sans-serif; | |
} | |
body { | |
background-color: var(--bg); | |
color: var(--fg); | |
height: 100vh; | |
display: grid; | |
place-items: center; | |
transition: | |
background-color var(--trans-dur), | |
color var(--trans-dur); | |
} | |
.t, | |
.t__inner, | |
.t__inner:before, | |
.t__inner:after, | |
.t__drag { | |
border-radius: 50%; | |
} | |
.t { | |
--temp-hue: 50; | |
box-shadow: | |
0 0 0.1em hsl(var(--hue),10%,90%), | |
0 0 0.3em hsl(var(--hue),10%,80%), | |
0 0 0.1em hsl(var(--hue),10%,40%) inset; | |
display: grid; | |
place-items: center; | |
position: relative; | |
width: 16em; | |
height: 16em; | |
transition: box-shadow 0.3s; | |
z-index: 0; | |
} | |
.t__inner { | |
background-color: hsl(var(--hue),10%,80%); | |
position: relative; | |
width: 11.5em; | |
height: 11.5em; | |
transition: background-color 0.3s; | |
} | |
.t__inner:before, | |
.t__inner:after { | |
content: ""; | |
display: block; | |
position: absolute; | |
} | |
.t__inner:before { | |
background-image: linear-gradient(hsl(var(--hue),10%,95%),hsl(var(--hue),10%,65%)); | |
top: -0.25em; | |
left: -0.25em; | |
width: 12em; | |
height: 12em; | |
z-index: -1; | |
} | |
.t__inner:after { | |
background-image: linear-gradient(hsl(var(--temp-hue),90%,100%),hsl(var(--temp-hue),90%,50%)); | |
box-shadow: | |
0 -0.25em 2em hsla(var(--temp-hue),90%,55%,0.3), | |
0 2em 1em hsl(var(--temp-hue),20%,55%); | |
top: -0.25em; | |
left: -0.375em; | |
width: 12.25em; | |
height: 12.25em; | |
z-index: -2; | |
} | |
.t__drag, | |
.t__value, | |
.t__units { | |
position: absolute; | |
} | |
.t__drag, | |
.t__unit { | |
background: transparent; | |
-webkit-appearance: none; | |
appearance: none; | |
} | |
.t__drag { | |
cursor: grab; | |
display: block; | |
width: 100%; | |
height: 100%; | |
z-index: 2; | |
-webkit-tap-highlight-color: transparent; | |
} | |
.t__drag:focus { | |
outline: transparent; | |
} | |
.t__arrows { | |
display: block; | |
position: absolute; | |
top: -2.25em; | |
left: -2.25em; | |
opacity: 0; | |
width: 16em; | |
height: auto; | |
transition: opacity 0.15s linear; | |
z-index: 1; | |
} | |
.t__drag:not(.t__drag--dragging):hover ~ .t__arrows { | |
opacity: 1; | |
transition-delay: 0.3s; | |
} | |
.t__drag--dragging ~ .t__arrows { | |
opacity: 0; | |
transition-delay: 0s; | |
} | |
.t__drag--dragging ~ .t__units { | |
z-index: 0; | |
} | |
.t__value, | |
.t__unit { | |
text-shadow: 0 0.15em 0.1em hsla(var(--hue),10%,10%,0.1); | |
} | |
.t__value { | |
display: flex; | |
justify-content: flex-end; | |
align-items: center; | |
padding-right: 3em; | |
inset: 0; | |
z-index: 0; | |
} | |
.t__digit, | |
.t__degree { | |
display: inline-block; | |
line-height: 1; | |
-webkit-user-select: none; | |
user-select: none; | |
} | |
.t__digit { | |
font-size: 3em; | |
font-weight: 300; | |
text-align: center; | |
width: 1ch; | |
} | |
.t__degree { | |
color: hsl(var(--hue),10%,50%); | |
font-size: 2em; | |
transform: translateY(-0.5ch); | |
} | |
.t__units { | |
top: calc(50% - 1.5em); | |
right: 1.5em; | |
z-index: 3; | |
} | |
.t__unit { | |
color: hsl(var(--hue),10%,65%); | |
display: block; | |
font-size: 1em; | |
font-weight: 500; | |
line-height: 1; | |
width: 1.5em; | |
height: 1.5em; | |
} | |
.t__unit[aria-pressed="true"] { | |
color: currentColor; | |
} | |
.t__sr { | |
clip: rect(1px,1px,1px,1px); | |
overflow: hidden; | |
position: absolute; | |
width: 1px; | |
height: 1px; | |
} | |
/* Dark theme */ | |
@media (prefers-color-scheme: dark) { | |
:root { | |
--bg: hsl(var(--hue),10%,20%); | |
--fg: hsl(var(--hue),10%,90%); | |
} | |
.t { | |
box-shadow: | |
0 0 0.1em hsl(var(--hue),10%,40%), | |
0 0 0.3em hsl(var(--hue),10%,30%), | |
0 0 0.1em hsl(var(--hue),10%,0%) inset; | |
} | |
.t__inner { | |
background-color: hsl(var(--hue),10%,30%); | |
} | |
.t__inner:before { | |
background-image: linear-gradient(hsl(var(--hue),10%,45%),hsl(var(--hue),10%,15%)); | |
} | |
.t__inner:after { | |
background-image: linear-gradient(hsl(var(--temp-hue),90%,10%),hsl(var(--temp-hue),90%,50%)); | |
box-shadow: | |
0 -0.25em 2em hsla(var(--temp-hue),90%,55%,0.3), | |
0 2em 1em hsl(var(--temp-hue),20%,25%); | |
} | |
.t__value { | |
text-shadow: 0 0.15em 0.1em hsla(var(--hue),10%,10%,0.2); | |
} | |
.t__degree { | |
color: hsl(var(--hue),10%,70%); | |
} | |
.t__unit { | |
color: hsl(var(--hue),10%,45%); | |
} | |
} |
<link href="https://fonts.googleapis.com/css2?family=Montserrat:wght@300;400;500&display=swap" rel="stylesheet" /> |