Vue countdown timer prints out on console.log but don't get passed on as data

Question

I am using moment js to countdown the time as 10,9,8,7,6 . It successfully counts down time on console.log but I am not able to pass that as a data.

Below is my code on jsfiddle

https://jsfiddle.net/ujjumaki/817bqn52/9/

Answer 1

Change the function inside setInterval to an arrow functions, in order to read this as the Vue component:

setInterval(() => {
      duration.subtract(interval, "milliseconds"); //using momentjs substract function
      this.countdownTimer = moment(duration.asMilliseconds()).format('s'); 
      console.log(moment(duration.asMilliseconds()).format('s'));
      /* countdown timer works for console.log */
}, interval );