Flutter - how avoid pushing same route twice? - flutter

Question

This structure of my app navigation:
CupertinoTabScaffold ->tabBuilder:TabPage-> tabBar: CupertinoTabBar
My TabPage:
return MaterialApp(
navigatorKey: navKey,
home: child,
);
I have separate navigation in each tab. by clicking on the bottom tab, I go back to the beginning. this is my code and this is working now:
key.currentState!.pushNamedAndRemoveUntil('/', ModalRoute.withName('/'));
for each tab I have my own navigation key. I pass it to each TabPage.
but if the page is at the root I need to avoid pushing same route twice. I tried this code but it doesn't work:
key.currentState!.pushNamedAndRemoveUntil("/",
(route) => route.isFirst && route.settings.name == "/" ? false : true);
how avoid pushing same route twice?

Answer 1

Navigator.of(context).pushNamedAndRemoveUntil(
"newRouteName",
(route) => route.isCurrent && route.settings.name == "newRouteName"
? false
: true);
t will pop the current route if name of the route is "newRouteName" and then push new one, else will not pop anything.
Edit: Latest flutter provides ModalRoute.of(context).settings.name to get the name of current route.

Answer 2

If you're using a BottomNavigationBar, you can simply add a checker on onTap() to see if you're going to navigate on the same page. To track the current page, you can either use enum or a simple variables like int. CupertinoTabBar also have an onTap property available similar to BottomNavigationBar.
BottomNavigationBar(
items: <BottomNavigationBarItem>[...],
currentIndex: _currentPage,
onTap: (value){
// Only navigate if a different page was clicked
if(value != _currentPage){
_currentPage = value;
setState(() {
switch(value) {
// Page 0
case 0:
key.currentState!.pushReplacementNamed(...);
break;
// Page 1
case 1:
key.currentState!.pushReplacementNamed(...);
break;
...
}
});
}
}
)
Or if you're using a TabBar with TabBarView, the page displayed can be managed by the controller as demonstrated in this guide.

Answer 3

This will pop the current route if name of the route is the new Route Name and then push new one, else will not pop any route.
Navigator.of(context).pushNamedAndRemoveUntil(
"new",
(route) => route.isCurrent && ModalRoute.of(context).settings.name == "new"
? false
: true);