Marks this field as being observable, and tells the system to observe the specified fields for changes, and automatically revalidate the
view when they change. If no fields are specified, all fields are observed.
Parameters
fields: string[] = ...
fields to be observed, if ommitted, all fields are observed
Marks this field as being observable, and tells the system to observe the specified fields for changes, and automatically revalidate the view when they change. If no fields are specified, all fields are observed.