Custom component interacting with the rest of the form

[aeberhart]

Reading other values:

A custom component does get a copy of the root form value, however, this value is not updated if it changes by interacting with the form.

Writing other values:

There are cases where a custom component might have to write other form fields. Currently this is only possible if the custom component "controls" the entire object. A possibility might be emitting another kind of change event to the parent. The parent can then send it up to its parent or treat it like an "internal" change.