EmberJS 2.10 How to properly set nested route controller to set actions on the route?

I'm a little confused with the controller asigned to a route.

I want to create an action called "showModal" on the route but when I use this code ember sends an error that the action is not defined on the route:

export default Ember.Route.extend({


actions: {


    showModal: function (params) {

        console.info(params);

        if (params) {

            Custombox.open({
                target: '.mModal',
                closer: false
            });

        } else {

            Custombox.close();

        }

    }

  }

});

However, if I use the next code all seems to work fine, the modal action can be called by any component:

export default Ember.Route.extend({


setupController: function (controller, model) {

    this._super(...arguments);
    controller.set('actions', this.actions);
},

actions: {


    showModal: function (params) {

        console.info(params);

        if (params) {

            Custombox.open({
                target: '.mModal',
                closer: false
            });

        } else {

            Custombox.close();

        }

    }

}

});

I would like to know, how can I assign a controller to a route? so the actions will be correctly defined on the route.

By the way I use the next ember-cli command to create my route: ember g route new/quote