I have created this stopwatch and it runs pretty well. The only problem that I am having is that whenever I click my "stop" button, the time stops on the screen but it is still running in the background.
Is there any way to stop this from happening? I want the timer to stop on its current time, then when I click "start", it resumes from the time it was stopped on.
Im thinking maybe create a "new Date()" variable before the update function and another "new Date()" variable inside of the update function and somehow subtract those to get the current date. But I cannot figure that out either.
start = document.getElementById('Start');
stop = document.getElementById('Stop');
let watchRunning = false;
Start.addEventListener('click', startHandler);
Stop.addEventListener('click', stopHandler);
function startHandler() {
if (!watchRunning) {
watchRunning = setInterval(update, 70);
}
}
function stopHandler() {
clearInterval(watchRunning);
watchRunning = null;
}
update();
var seconds;
var milliseconds;
var d;
function update() {
d = new Date();
seconds = d.getSeconds();
milliseconds = Math.floor((d.getMilliseconds() / 10));
if (milliseconds < 10 && seconds < 10) {
document.getElementById("Time").innerHTML =
"0" + seconds + ".0" + milliseconds;
} else if (milliseconds < 10 && seconds >= 10) {
document.getElementById("Time").innerHTML =
seconds + ".0" + milliseconds;
} else if (milliseconds >= 0 && seconds < 10) {
document.getElementById("Time").innerHTML =
"0" + seconds + "." + milliseconds;
} else if (milliseconds >= 0 && seconds >= 10) {
document.getElementById("Time").innerHTML =
seconds + "." + milliseconds;
}
}
#Time {
background-color: yellow;
max-width: 2.3%;
}
<h1>Stop Watch</h1>
<button id="Start">Start</button>
<button id="Stop">Stop</button>
<h3>Elapsed Time:</h3>
<p id="Time"></p>
Try running the snippet and you will see what I mean. The time doesn't stop "running" after I click stop, and when I click start it resumes as if it was never stopped.