离开页面时取消定时器

interval.js

        var promise;

        // 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(getOrderList, 5000);
            console.log("start");
        };

        // stops the interval
        $scope.stop = function() {
            $interval.cancel(promise);
            console.log("cancel");
        };

        // starting the interval by default
        $scope.start();

        $scope.$on('$destroy', function() {
            $scope.stop();
        });
        
        function getOrderList() {
            // get restaurant list request
            $http({
                method: 'GET',
                url: 'http://202.120.40.175:21104/order/unconfirmedorder',
                crossDomain: true
            }).success(function (orderArr) {
                console.log("get all order list successed");
                $scope.rowCollection = orderArr;
                $scope.displayedCollection = $scope.rowCollection;
            }).error(function () {
                console.log("get order list failed");
            });


            //202.120.40.175:21104/order/unconfirmedorder
        }