onWillPop assert error for custom navbar

[zhell]

Hello,

I keep getting this error on a custom nav bar :
════════ Exception caught by widgets library ═══════════════════════════════════
If you declare the onWillPop function, you will have to handle the back function functionality yourself as your onWillPop function will override the defualt function.
'package:persistent_bottom_nav_bar/persistent_tab_view.widget.dart':
persistent_tab_view.widget.dart:1
Failed assertion: line 107 pos 16: 'handleAndroidBackButtonPress && onWillPop != null'

It seems like you missed the assert correction for the "custom" widget constructor.

There is also a small typo on the assert message "default"

Edit : There are actually 2 PR created to fix this issue, #309 & #336, one of them need to be merged to fix this error