Understanding actions in components after 1.13


Hi, I’d like to have some help understanding how I should handle one-way binding in components after 1.13.

For example, if I have a simple each in a template:

{{#each model as |item|}}
    {{editable-item item=item submit=(action 'saveItem')}}

The component template has all display stuff but also allows users to edit item’s content and save the changes on the item pressing a button.


{{input value=item.title enter='edit'}}
{{input value=item.foo enter='edit}}
{{input value=item.bar enter='edit}}


import Ember from "ember";

export default Ember.Component.extend({
  actions: {
    edit() {

Should I send the item as parameter and then re-find it from the store on the route and finally save it to the server. Or should I send the submit function a parameter per each item field? Or is this all wrong? I’d like to know what’s the Ember way to handle actions now.



You might want to take a look at the Improved Actions RFC that describes how the closure actions are designed to work.


That looks all good except I’m not sure that the edit action in the component will be fired automatically as it is, to my knowledge, not a UI event.

Other than that, the way it is set up now, the saveItem action handler in your controller will receive the item that was edited/clicked/whatever and can then save it:

actions: {
  saveItem(item) {
    return item.save();


Curious why these are called “closure actions”. What is the closure, what is being closed over?

The RFC says

closed over functions

I have no idea what this means.


They are closed over the variables in their (template) scope :slight_smile: including the scope.

// app/templates/application.hbs
{{! scope here is controller, the action helper creates a closure that binds the scope as oppose to...}}
{{#my-component do-things=(action "action")}}

// app/templates/components/my-component.hbs
{{! the scope here is the component, the resulting closure binds the component as the action handler's "this" }}
{{yield (action "action")}}