How can I create a countdown from a Date().getTime() in Javascript?

Question

I have an click function who get a number from Date().getTime(). I want to take this number and convert him in a countdown on my view.

I'm using only javascript with Ionic framework 1x.

var currentDate = new Date().getTime();
console.log(currentDate);

var secondDate = new Date(item.date).getTime();
console.log(secondDate);
secondDate = new Date(secondDate).getSeconds();
console.log(secondDate);
$scope.countdown = secondDate;

Answer 1

In plain JavaScript you can make use of setInterval like this:

setInterval(function() {
  console.log(new Date().getTime());
}, 1000);

In Ionic/Angular, you'll need to replace setInterval with the wrapper $interval:

$interval(function() {
  $scope.countdown = new Date().getTime();
}, 1000);