How to move focus to a field the angular way

angular-focus-example.html

...
<textarea focus-on="IWantFocusWhenButtonClicked"></textarea>
<button ng-click="doFocus()">Focus</button>
...

controller.js

...
$scope.doFocus = function() {
  $scope.$broadcast("focus:IWantFocusWhenButtonClicked");
}

focus-directive.js

angular.directive('focusOn', ['$timeout', ($timeout) => {
        return {
            restrict: 'A',
            link: (scope, element, attr) => {
                scope.$on("focus:" + attr.focusOn, () => {
                    $timeout(element[0].focus());
                });
            }
        };
    }]);