javascript css reactjs timer requestanimationframe

Canceling stop the animation made with requestAnimationFrame()

I'm making a timer progress bar animation in react. I'm doing this using requestAnimationFrame(). The issue I have is that I cannot stop that animation with cancelAnimationFrame() despite setting an id to the animation and then referring to that id while cancelling (handleStop func). Why?

Edit: Hmm, maybe it stops requestAnimationFrame() but it won't stop transform animation that was already set?

const { useState, useEffect } = React;


const App = () => {
  const totalTime = 10000;
  const [timeLeft, setTimeLeft] = useState(null);
  const [timerId, setTimerId] = useState(null);

  useEffect(() => {
      setTimeLeft(totalTime);

      const start = performance.now();
      const animate = (time) => {
        const elapsedTime = time - start;
        setTimeLeft((prevTimeLeft) => {
          if (prevTimeLeft !== null && prevTimeLeft > 0) {
            const remainingTime = Math.max(totalTime - elapsedTime, 0);
            requestAnimationFrame(animate);
            return remainingTime;
          }
          return 0;
        });
      };

    const id = requestAnimationFrame(animate);
    setTimerId(id);

    return () => {
      cancelAnimationFrame(id);
    };
  }, []);

  const handleStop = () => {
    if (timerId) {
      cancelAnimationFrame(timerId);
      setTimerId(null);
    }
  };

  return (
    <div>
      <div className="progress-bar">
        <div
          style={{
            transform: `scaleX(${timeLeft ? timeLeft / totalTime : 0})`,
          }}
        />
      </div>
      <button onClick={handleStop}>Pause the animation</button>
    </div>
  );
};

ReactDOM.render(<App />, document.getElementById("root"));

.progress-bar {
  height: 10px;
  width: 300px;
  background-color: #fdb913;
  border-radius: 10px;
  overflow: hidden;
  margin-top: 2rem;
  margin-bottom: 3rem;
}

.progress-bar div {
  background-color: grey;
  height: 100%;
  transform-origin: left center;
}

<div id="root">
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/18.1.0/umd/react.production.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react-dom/18.1.0/umd/react-dom.production.min.js"></script>

</div>

Solution

Maybe you can try these steps.

Do not call requestAnimationFrame in setState() callback function.
Try use useRef() instead of useState() to manage timer id.

I wrote the code with those steps and it worked well in this code sandbox.

  const timerRef = useRef(null);

  useEffect(() => {
    setTimeLeft(totalTime);

    const start = performance.now();
    const animate = (time) => {
      const elapsedTime = time - start;
      setTimeLeft((prevTimeLeft) => {
        if (prevTimeLeft !== null && prevTimeLeft > 0) {
          const remainingTime = Math.max(totalTime - elapsedTime, 0);
          return remainingTime;
        }
        return 0;
      });
      timerRef.current = requestAnimationFrame(animate);
    };

    timerRef.current = requestAnimationFrame(animate);

    return () => {
      if (timerRef.current !== null) {
        cancelAnimationFrame(timerRef.current);
        timerRef.current = null;
      }
    };
  }, []);