BottomNavigationBar color incorrectly change - flutter

Question

I've a bottomnavigation bar that has a color. When I clicked on the last button, the color change to white ...
The last button show some card i can swipe.
For that i use the code here : https://github.com/devefy/Flutter-Story-App-UI
i've tried to change return container() whith something else, but nothing was heplful.
here is my code
void _onItemTapped(int index) {
setState(() {
if (edifice != null) _selectedIndex = index;
});
}
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text(widget.unEdifice.vocable),
backgroundColor: color_edifices,
),
body: Center(
child: edifice == null
? CircularProgressIndicator()
: _selectedIndex == 5
? SingleChildScrollView(
child: Column(
children: <Widget>[
Stack(
children: <Widget>[
CardScrollWidget(currentPage),
Positioned.fill(
child: PageView.builder(
itemCount: edifice.commentaires.length,
controller: controller,
reverse: true,
itemBuilder: (context, index) {
return Container(
);
},
),
)
],
),
],
),
)
: _widgetOptions.elementAt(_selectedIndex),
),
bottomNavigationBar: BottomNavigationBar(
items: const <BottomNavigationBarItem>[
BottomNavigationBarItem(
backgroundColor: color_edifices,
icon: Icon(GaeoIcons.church, color: Colors.white),
title: Text('Edifice', style: buttonTextStyle),
),
BottomNavigationBarItem(
icon: Icon(GaeoIcons.location_on, color: Colors.white),
title: Text('Adresses', style: buttonTextStyle),
),
BottomNavigationBarItem(
icon: Icon(GaeoIcons.group, color: Colors.white),
title: Text('Responsables', style: buttonTextStyle),
),
BottomNavigationBarItem(
icon: Icon(GaeoIcons.truck, color: Colors.white),
title: Text('Distributions', style: buttonTextStyle),
),
BottomNavigationBarItem(
icon: Icon(GaeoIcons.group, color: Colors.white),
title: Text('Contacts', style: buttonTextStyle),
),
BottomNavigationBarItem(
icon: Icon(GaeoIcons.comment, color: Colors.white),
title: Text('Commentaires', style: buttonTextStyle),
),
],
currentIndex: _selectedIndex,
selectedItemColor: Colors.amber[800],
onTap: _onItemTapped,
),
);
}
}`
You can see what i mean with the pictures included
Thanks for your help

Answer 1

I have tried to simulate your case with Story App UI
please try to
1. add BottomNavigationBar 's backgroundColor
2. test with BottomNavigationBarType.fixed and fixedColor
also reference Flutter BottomNavigationBar Colors
code snippet
bottomNavigationBar: BottomNavigationBar(
backgroundColor: Colors.brown,
type: BottomNavigationBarType.fixed,
fixedColor: Colors.white,
items: const <BottomNavigationBarItem>[
BottomNavigationBarItem(
backgroundColor: Colors.white,
icon: Icon(Icons.access_time, color: Colors.white),
title: Text('Edifice', ),
),
BottomNavigationBarItem(
icon: Icon(Icons.access_alarm, color: Colors.white),
title: Text('Adresses', ),
),
],
)
Test result of Story App UI with BottomNavigationBar