i don't know if your wish is possible but if you can use frames u can use one webview.
you can set the target to the frame name. https://wiki.selfhtml.org/wiki/HTML/Frames
thats easy
i saw this event even but the description for it is a little bit hidden in the webview description itself.
GotoUrl or GotoUrlValidate would be more intuitive https://www.b4x.com/android/help/views.html#webview