Initialize the part with internal fields
User callbacks for implementing logic to release any resources/subscriptions
that may have been retained by this directive. Since directives may also be
re-connected, reconnected
should also be implemented to restore the
working state of the directive prior to the next render.
Optional
_ref: RefOrCallback<Element>Sets the value of the directive's Part outside the normal update
/render
lifecycle of a directive.
This method should not be called synchronously from a directive's update
or render
.
The value to set
The type of the class that powers this directive. Necessary for naming the directive's return type.