[Vuejs]-JavaScript – how to toggle setInterval

toggleInterval() {
      let handler;
      this.switcher = !this.switcher;

      if (this.switcher) {
        handler = () => {
          console.log('This is first interval');
        };
      } else {
        handler = () => {
          console.log('This is first interval');
        };
      }
      clearInterval(this.intervalId);
      this.intervalId = setInterval(handler, 1000);
},

info on setInterval