AngularJS - pass parameters out from the Custom Directory

AngularJS - pass parameters out from the Custom Directory

//Controller

angular.module('b1').controller('WarehousePurchaseEdit', function (){
    c.onPurchaseDateChange = function (param) {
        alert(param);
    }
}


//View
<div ext-on-changes purchase="c.model" handler="c.onPurchaseDateChange"></div>
//Directory
angular.module('b1').directive("extOnChanges", function ($translate) {
    return {
        scope: {
            purchase: '=',
            handler: '&'
        },
        template: 'Current date: {{purchase.purchaseDate}}, current warehouse: {{purchase.warehouseName}}' +
            '<button ng-click="s.clickFromDirective()">Call Controller function</button>    ',
        controllerAs: 's',
        controller: function ($scope) {
            var s = this;
            s.clickFromDirective = function (){
                $scope.handler()($scope.purchase.purchaseDate);
            }
        }
    }
});