How to make a ticking clock (time) in AngularJS an

Question

I'm a beginner AngularJS/html user who's been trying to find a code snippet to make a clock/time item for a web app.

A web search did not provide straight-forward results as easily as I would expect them for something so trivial, so I thought I would post this question to get some answers and also make this easier to find for others.

I have posted my solution but want to see if there is anything nicer out there before choosing an answer!

Answer 1

There is an example of how to achieve this using interval from the Angular docs. You can also try it out in plunker.

Here is the code:

Javascript:

<script>
  angular.module('intervalExample', [])
    .controller('ExampleController', ['$scope', '$interval',
      function($scope, $interval) {
        $scope.format = 'M/d/yy h:mm:ss a';
        $scope.blood_1 = 100;
        $scope.blood_2 = 120;

        var stop;
        $scope.fight = function() {
          // Don't start a new fight if we are already fighting
          if ( angular.isDefined(stop) ) return;

          stop = $interval(function() {
            if ($scope.blood_1 > 0 && $scope.blood_2 > 0) {
              $scope.blood_1 = $scope.blood_1 - 3;
              $scope.blood_2 = $scope.blood_2 - 4;
            } else {
              $scope.stopFight();
            }
          }, 100);
        };

        $scope.stopFight = function() {
          if (angular.isDefined(stop)) {
            $interval.cancel(stop);
            stop = undefined;
          }
        };

        $scope.resetFight = function() {
          $scope.blood_1 = 100;
          $scope.blood_2 = 120;
        };

        $scope.$on('$destroy', function() {
          // Make sure that the interval is destroyed too
          $scope.stopFight();
        });
      }])
    // Register the 'myCurrentTime' directive factory method.
    // We inject $interval and dateFilter service since the factory method is DI.
    .directive('myCurrentTime', ['$interval', 'dateFilter',
      function($interval, dateFilter) {
        // return the directive link function. (compile function not needed)
        return function(scope, element, attrs) {
          var format,  // date format
              stopTime; // so that we can cancel the time updates

          // used to update the UI
          function updateTime() {
            element.text(dateFilter(new Date(), format));
          }

          // watch the expression, and update the UI on change.
          scope.$watch(attrs.myCurrentTime, function(value) {
            format = value;
            updateTime();
          });

          stopTime = $interval(updateTime, 1000);

          // listen on DOM destroy (removal) event, and cancel the next UI update
          // to prevent updating time after the DOM element was removed.
          element.on('$destroy', function() {
            $interval.cancel(stopTime);
          });
        }
      }]);
</script>

HTML

<div>
  <div ng-controller="ExampleController">
    <label>Date format: <input ng-model="format"></label> <hr/>
    Current time is: <span my-current-time="format"></span>
    <hr/>
    Blood 1 : <font color='red'>{{blood_1}}</font>
    Blood 2 : <font color='red'>{{blood_2}}</font>
    <button type="button" data-ng-click="fight()">Fight</button>
    <button type="button" data-ng-click="stopFight()">StopFight</button>
    <button type="button" data-ng-click="resetFight()">resetFight</button>
  </div>
</div>

Here is the result: