<div id="app"></div>
body {
font-family: sans-serif;
display: grid;
height: 100vh;
place-items: center;
}
.base-timer {
position: relative;
width: 300px;
height: 300px;
}
.base-timer__svg {
transform: scaleX(-1);
}
.base-timer__circle {
fill: none;
stroke: none;
}
.base-timer__path-elapsed {
stroke-width: 7px;
stroke: grey;
}
.base-timer__path-remaining {
stroke-width: 7px;
stroke-linecap: round;
transform: rotate(90deg);
transform-origin: center;
transition: 1s linear all;
fill-rule: nonzero;
stroke: currentColor;
}
.base-timer__path-remaining.green {
color: rgb(65, 184, 131);
}
.base-timer__path-remaining.orange {
color: orange;
}
.base-timer__path-remaining.red {
color: red;
}
.base-timer__label {
position: absolute;
width: 300px;
height: 300px;
top: 0;
display: flex;
align-items: center;
justify-content: center;
font-size: 48px;
}
// Credit: Mateusz Rybczonec
const FULL_DASH_ARRAY = 283;
const WARNING_THRESHOLD = 10;
const ALERT_THRESHOLD = 5;
const COLOR_CODES = {
info: {
color: "green"
},
warning: {
color: "orange",
threshold: WARNING_THRESHOLD
},
alert: {
color: "red",
threshold: ALERT_THRESHOLD
}
};
const TIME_LIMIT = 20;
let timePassed = 0;
let timeLeft = TIME_LIMIT;
let timerInterval = null;
let remainingPathColor = COLOR_CODES.info.color;
document.getElementById("app").innerHTML = `
<div class="base-timer">
<svg class="base-timer__svg" viewBox="0 0 100 100" xmlns="http://www.w3.org/2000/svg">
<g class="base-timer__circle">
<circle class="base-timer__path-elapsed" cx="50" cy="50" r="45"></circle>
<path
id="base-timer-path-remaining"
stroke-dasharray="283"
class="base-timer__path-remaining ${remainingPathColor}"
d="
M 50, 50
m -45, 0
a 45,45 0 1,0 90,0
a 45,45 0 1,0 -90,0
"
></path>
</g>
</svg>
<span id="base-timer-label" class="base-timer__label">${formatTime(
timeLeft
)}</span>
</div>
`;
startTimer();
function onTimesUp() {
clearInterval(timerInterval);
}
function startTimer() {
timerInterval = setInterval(() => {
timePassed = timePassed += 1;
timeLeft = TIME_LIMIT - timePassed;
document.getElementById("base-timer-label").innerHTML = formatTime(
timeLeft
);
setCircleDasharray();
setRemainingPathColor(timeLeft);
if (timeLeft === 0) {
onTimesUp();
}
}, 1000);
}
function formatTime(time) {
const minutes = Math.floor(time / 60);
let seconds = time % 60;
if (seconds < 10) {
seconds = `0${seconds}`;
}
return `${minutes}:${seconds}`;
}
function setRemainingPathColor(timeLeft) {
const { alert, warning, info } = COLOR_CODES;
if (timeLeft <= alert.threshold) {
document
.getElementById("base-timer-path-remaining")
.classList.remove(warning.color);
document
.getElementById("base-timer-path-remaining")
.classList.add(alert.color);
} else if (timeLeft <= warning.threshold) {
document
.getElementById("base-timer-path-remaining")
.classList.remove(info.color);
document
.getElementById("base-timer-path-remaining")
.classList.add(warning.color);
}
}
function calculateTimeFraction() {
const rawTimeFraction = timeLeft / TIME_LIMIT;
return rawTimeFraction - (1 / TIME_LIMIT) * (1 - rawTimeFraction);
}
function setCircleDasharray() {
const circleDasharray = `${(
calculateTimeFraction() * FULL_DASH_ARRAY
).toFixed(0)} 283`;
document
.getElementById("base-timer-path-remaining")
.setAttribute("stroke-dasharray", circleDasharray);
}
This Pen doesn't use any external CSS resources.
This Pen doesn't use any external JavaScript resources.