pub type NavObserver = dyn Fn(&str, Option<&str>);Expand description
A navigation observer (§14.6): called with the new FULL route each time it changes, from any
source — imperative navigate/nav_back, a nav_link or sidebar row (which navigate from an
event handler, bypassing the event observer), a stack push, or a native back gesture. "" is
the root. Installed by the recorder in day-script; day-core only fires it.