angularjs 定时器 销毁

angular.module('app', [])

  .controller('ItemController', function($scope, $interval) {
  
    // store the interval promise in this variable
    var promise;
  
    // simulated items array
    $scope.items = [];
    
    // starts the interval
    $scope.start = function() {
      // stops any running interval to avoid two intervals running at the same time
      $scope.stop(); 
      
      // store the interval promise
      promise = $interval(setRandomizedCollection, 1000);
    };
  
    // stops the interval
    $scope.stop = function() {
      $interval.cancel(promise);
    };
  
    // starting the interval by default
    $scope.start();
 
    // stops the interval when the scope is destroyed,
    // this usually happens when a route is changed and 
    // the ItemsController $scope gets destroyed. The
    // destruction of the ItemsController scope does not
    // guarantee the stopping of any intervals, you must
    // be responsible for stopping it when the scope is
    // is destroyed.
    $scope.$on('$destroy', function() {
      $scope.stop();
    });
            
    function setRandomizedCollection() {
      // items to randomize 1 - 11
      var randomItems = parseInt(Math.random() * 10 + 1); 
        
      // empties the items array
      $scope.items.length = 0; 
      
      // loop through random N times
      while(randomItems--) {
        
        // push random number from 1 - 10000 to $scope.items
        $scope.items.push(parseInt(Math.random() * 10000 + 1)); 
      }
    }
  
  });