Exception caught by widgets library A build function returned null - flutter

Question

I am fairly new to flutter development. I am trying to have static header and grid card items that scroll underneath the static header, but I end up getting the error. I have tried to research no success. What am i doing wrong?
Exception caught by widgets library A build function returned null.
The relevant error-causing widget was: GridDashboard
and
A RenderFlex overflowed by 99515 pixels on the bottom. The relevant
error-causing widget was: Column
my griddashboard class
class GridDashboard extends StatelessWidget {
var services = [
"Home",
"Settings",
"Supervisor",
"Logout",
"Forms",
"Messages",
"bluetooth",
"Check for updates",
"Update"
];
var images = [
"images/calendar.png",
"images/festival.png",
"images/food.png",
"images/image.png",
"images/logout.png",
"images/setting.png",
"images/note.png",
"images/todo.png",
"images/map.png",
];
#override
Widget build(BuildContext context) {
// return Padding(
// padding: const EdgeInsets.all(8.0),
// child:
GridView.builder(
itemCount: services.length,
gridDelegate: SliverGridDelegateWithFixedCrossAxisCount(
crossAxisCount: 3,
childAspectRatio: MediaQuery.of(context).size.width/(MediaQuery.of(context).size.height/1.4)
),
itemBuilder: (BuildContext context, int index){
return Card(
child: Column(
children: <Widget>[
SizedBox(
height: 20,
),
Image.asset(images[index], height: 50.0, width: 50.0,),
Padding(
padding: const EdgeInsets.all(20.0),
child: Text(services[index], style: TextStyle(fontSize: 16.0, height: 1.2),textAlign: TextAlign.center ,),
)
],
),
);
},
// ),
);
}
}
my home class
class Home extends StatefulWidget {
#override
HomeState createState() => new HomeState();
}
class HomeState extends State<Home> {
#override
Widget build(BuildContext context) {
return Scaffold(
backgroundColor: Color(0xff392850),
body: Column(
children: <Widget>[
SizedBox(
height: 110,
),
Padding(
padding: EdgeInsets.only(left: 16, right: 16),
child: Row(
mainAxisAlignment: MainAxisAlignment.spaceBetween,
children: <Widget>[
Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: <Widget>[
Text(
"Full Names",
style: GoogleFonts.openSans(
textStyle: TextStyle(
color: Colors.white,
fontSize: 18,
fontWeight: FontWeight.bold)),
),
SizedBox(
height: 4,
),
Text(
"Home",
style: GoogleFonts.openSans(
textStyle: TextStyle(
color: Color(0xffa29aac),
fontSize: 14,
fontWeight: FontWeight.w600)),
),
],
),
IconButton(
alignment: Alignment.topRight,
icon: Image.asset(
"assets/notification.png",
width: 24,
),onPressed: ()=>{
},
),
],
),
),
SizedBox(
height: 40,
),
GridDashboard()
],
),
);
}
}

Answer 1

You removed the return keyword from your build function, probably by accident.
GridView.builder(
needs to be
return GridView.builder(
Otherwise your build function returns nothing and you get the errors you are getting now.

Answer 2

as it says your build function was called on null which means you forgot write return out;
your problem is in griddashboard class where you wrote this
Widget build(BuildContext context) {
// return Padding(
// padding: const EdgeInsets.all(8.0),
// child:
GridView.builder(
itemCount: services.length
every time you don't write return in a function it shows that error , not only the build function , so you can handle it by writing return like this
Widget build(BuildContext context) {
return GridView.builder(
itemCount: services.length