Text not updating on pressing button in dialog - flutter

Question

I have a Text widget and two buttons to increase or decrease the count. + button to increase the count and - button to decrease the count. And the count is displayed in a Text widget. When I debug, count is changing but the Text is not updating. Not getting any error as well. How to do this. Here is my code:
_showDetails(BuildContext context, String barcodeResult) {
return showDialog(
context: context,
barrierDismissible: true,
builder: (BuildContext context) {
return Dialog(
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.circular(10.0)),
child: Container(
height: 350.0,
width: 200.0,
decoration:
BoxDecoration(borderRadius: BorderRadius.circular(20.0)),
child: Column(
children: <Widget>[
Stack(
children: <Widget>[
Container(
height: 150.0,
),
Container(
height: 100.0,
decoration: BoxDecoration(
borderRadius: BorderRadius.only(
topLeft: Radius.circular(10.0),
topRight: Radius.circular(10.0),
),
color: Colors.teal),
),
Positioned(
top: 50.0,
left: 94.0,
child: Container(
height: 90.0,
width: 90.0,
child: CircleAvatar(
ExactAssetImage(
'assets/images/user-image-default.png'),
),
),
)
],
),
SizedBox(
height: 20.0,
),
Padding(
padding: EdgeInsets.all(10.0),
child: Text(
name,
style: TextStyle(
fontSize: 14.0, fontWeight: FontWeight.w300),
),
),
Padding(
padding: EdgeInsets.all(10.0),
child: Text(
description,
style: TextStyle(
fontSize: 14.0, fontWeight: FontWeight.w300),
),
),
Padding(
padding: EdgeInsets.all(10.0),
child: Text(
'Price : $price',
style: TextStyle(
fontSize: 14.0, fontWeight: FontWeight.w300),
),
),
SizedBox(
height: 15.0,
),
Row(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
ClipOval(
child: Material(
color: Colors.teal, // button color
child: InkWell(
//splashColor: Colors.red, // inkwell color
child: SizedBox(
width: 40,
height: 40,
child: Icon(
Icons.add,
color: Colors.white,
)),
onTap: () {
setState(() {
// count++;
count = count + 1;
print(count);
});
},
),
),
),
SizedBox(
width: 20,
),
Text(count.toString()),
SizedBox(
width: 20,
),
ClipOval(
child: Material(
color: Colors.teal, // button color
child: InkWell(
// splashColor: Colors.red, // inkwell color
child: SizedBox(
width: 40,
height: 40,
child: Icon(
Icons.remove,
color: Colors.white,
)),
onTap: () {
setState(() {
//count--;
count = count - 1;
print(count);
});
},
),
),
),
],
),
],
),
),
);
});
}

Answer 1

Screenshot:
Here is the working code.
_showDetails(BuildContext context, String barcodeResult) {
return showDialog(
context: context,
barrierDismissible: true,
builder: (BuildContext context) {
return StatefulBuilder(builder: (context, setState) {
return Dialog(
shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(10.0)),
child: Container(
height: 350.0,
width: 200.0,
decoration: BoxDecoration(borderRadius: BorderRadius.circular(20.0)),
child: Column(
children: <Widget>[
Stack(
children: <Widget>[
Container(
height: 150.0,
),
Container(
height: 100.0,
decoration: BoxDecoration(
borderRadius: BorderRadius.only(
topLeft: Radius.circular(10.0),
topRight: Radius.circular(10.0),
),
color: Colors.teal),
),
Positioned(
top: 50.0,
left: 94.0,
child: Container(
height: 90.0,
width: 90.0,
child: CircleAvatar(
backgroundImage: ExactAssetImage(chocolateImage),
),
),
)
],
),
SizedBox(
height: 20.0,
),
Padding(
padding: EdgeInsets.all(10.0),
child: Text(
name,
style: TextStyle(fontSize: 14.0, fontWeight: FontWeight.w300),
),
),
Padding(
padding: EdgeInsets.all(10.0),
child: Text(
description,
style: TextStyle(fontSize: 14.0, fontWeight: FontWeight.w300),
),
),
Padding(
padding: EdgeInsets.all(10.0),
child: Text(
'Price : \$${price * count}',
style: TextStyle(fontSize: 14.0, fontWeight: FontWeight.w300),
),
),
SizedBox(
height: 15.0,
),
Row(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
ClipOval(
child: Material(
color: Colors.teal, // button color
child: InkWell(
//splashColor: Colors.red, // inkwell color
child: SizedBox(
width: 40,
height: 40,
child: Icon(
Icons.add,
color: Colors.white,
)),
onTap: () {
setState(() {
// count++;
count = count + 1;
print(count);
});
},
),
),
),
SizedBox(
width: 20,
),
Text(count.toString()),
SizedBox(
width: 20,
),
ClipOval(
child: Material(
color: Colors.teal, // button color
child: InkWell(
// splashColor: Colors.red, // inkwell color
child: SizedBox(
width: 40,
height: 40,
child: Icon(
Icons.remove,
color: Colors.white,
)),
onTap: () {
setState(() {
//count--;
count = count - 1;
print(count);
});
},
),
),
),
],
),
],
),
),
);
});
});
}