add isRunning state to useTimer

Author: amrlabib

app/App.js

@@ -12,6 +12,7 @@ function MyTimer({ expiryTimestamp }) {
     pause,
     resume,
     restart,
+    isRunning,
   } = useTimer({ expiryTimestamp, onExpire: () => console.warn('onExpire called') });
 
 
@@ -36,6 +37,7 @@ function MyTimer({ expiryTimestamp }) {
       >
         Restart
       </button>
+      <p>{isRunning ? 'running' : 'not running'}</p>
     </div>
   );
 }

src/useTimer.js

@@ -5,6 +5,7 @@ export default function useTimer(settings) {
   const { expiryTimestamp: expiry, onExpire } = settings || {};
   const [expiryTimestamp, setExpiryTimestamp] = useState(expiry);
   const [seconds, setSeconds] = useState(Time.getSecondsFromExpiry(expiryTimestamp));
+  const [isRunning, setIsRunning] = useState(true);
   const intervalRef = useRef();
 
   function clearIntervalRef() {
@@ -16,11 +17,13 @@ export default function useTimer(settings) {
 
   function handleExpire() {
     clearIntervalRef();
+    setIsRunning(false);
     Validate.onExpire(onExpire) && onExpire();
   }
 
   function start() {
     if (!intervalRef.current) {
+      setIsRunning(true);
       intervalRef.current = setInterval(() => {
         const secondsValue = Time.getSecondsFromExpiry(expiryTimestamp);
         if (secondsValue <= 0) {
@@ -32,11 +35,13 @@ export default function useTimer(settings) {
   }
 
   function pause() {
+    setIsRunning(false);
     clearIntervalRef();
   }
 
   function resume() {
     if (!intervalRef.current) {
+      setIsRunning(true);
       intervalRef.current = setInterval(() => setSeconds((prevSeconds) => {
         const secondsValue = prevSeconds - 1;
         if (secondsValue <= 0) {
@@ -62,6 +67,6 @@ export default function useTimer(settings) {
 
 
   return {
-    ...Time.getTimeFromSeconds(seconds), start, pause, resume, restart,
+    ...Time.getTimeFromSeconds(seconds), start, pause, resume, restart, isRunning,
   };
 }