ios - How to listen Zoom in/out event of WKWebView -

i want hide/show navigationbar of uinavigationcontroller when wkwebview zooms out/in.

to hide or show uinavigationbar quite easy follows:

self.navigationcontroller?.navigationbarhidden = true 

but problem don't know put code.

i thinking intercept zoom event of wkwebview. may there other ways, comments welcome.

every wkwebview has scrollview property allows access uiscrollview part of the web view. can use uiscrollviewdelegate method, scrollviewdidscroll callbacks on when web view scrolls.

first, set scroll view delegate:

let webview = wkwebview(...) webview.scrollview.delegate = self 

then, implement delegate method scrollviewdidscroll , add logic hide , show navigation bar:

extension yourclass: uiscrollviewdelegate {      func scrollviewdidscroll(scrollview: uiscrollview) {         // can use position of scrollview show , hide nav bar here     } }