Flutter - How to add custom tabbar inside sliverappbar? - flutter

Question

I'm trying to implement a custom tab bar widget inside a SliverAppBar. So far I've tried wrapping my CustomTabBar within a PreferredSize widget.
Here's my code:
Widget _buildBody(){
return NestedScrollView(
headerSliverBuilder: (BuildContext context, bool boxIsScrolled) {
return <Widget>[
SliverAppBar(
leading: Container(),
backgroundColor: Colors.transparent,
expandedHeight: 200.0,
flexibleSpace: FlexibleSpaceBar(
collapseMode: CollapseMode.pin,
background: Column(
children: <Widget>[
Row(
mainAxisAlignment: MainAxisAlignment.spaceEvenly,
children: <Widget>[
Text(
"Item 1"
),
Text(
"Item 2"
),
Text(
"Item 3"
)
],
)
]),
),
bottom: PreferredSize(
preferredSize: Size.fromHeight(kToolbarHeight),
child: CustomTabWidget(
items: ['Challenge', 'My friends'],
activeColor: secondaryColor,
currentIndex: currentIndex,
backgroundColor: tabColor,
activeTextColor: Colors.white,
backgroundTextColor: Colors.white,
onTabSelect: (int index) {
onLeaderboardTabSelect(index);
},
),
),];
},
body: ListView.separated(
itemCount: 50,
itemBuilder: (context, index) {
return ListTile(
title: Text('row $index'),
);
},
separatorBuilder: (context, index) {
return Divider();
},
) // should return listview depending on the tab
);
}
CustomTabWidget
Widget build(BuildContext context) {
return Container(
height: height,
decoration: BoxDecoration(
color: backgroundColor,
borderRadius: BorderRadius.circular(
30.0,
),
),
child: Row(
mainAxisAlignment: MainAxisAlignment.spaceBetween,
children: _buildItems(context),
),
);
}
The code successfully shows the my custom tab bar widget but whenever I scroll down or tap another tab, it disappears.
I might have overlooked something within the code.
Can anyone help me?

Answer 1

this work on my project
class TabBarInSliverAppbar extends StatelessWidget {
#override
Widget build(BuildContext context) {
return DefaultTabController(
length: 2,
child: Scaffold(
body: CustomScrollView(
slivers: [
SliverAppBar(
title: Text("Tabbar in SliverAppbar Example"),
pinned: true,
floating: true,
bottom: TabBar(
tabs: <Widget>[
Tab(
text: "First Tab",
),
Tab(
text: "Second Tab",
),
],
),
),
SliverToBoxAdapter(
child: TabBarView(
children: <Widget>[
Center(
child: Text("First Tab"),
),
Center(
child: Text("Second Tab"),
),
],
),
),
],
),
),
);
}
}
you can also checki this link :Flutter TabBar and SliverAppBar that hides when you scroll down