Flutter Widget List on Body Output - flutter

Question

I'm trying to load content (Widget) dynamically (by a index).
However if I not use List all is working as expected:
class _MyHomePageState extends State<MyHomePage> {
final titleController = TextEditingController();
String titolo = '';
late Widget display; //This is the future widget
//List<Widget> display = <Widget>[];
//int displayIndex = 1;
initialize it:
#override
Widget build(BuildContext context) {
//display.add(calculator());
display = calculator();
and use it on body property:
body: display,
When I try to use a list:
class _MyHomePageState extends State<MyHomePage> {
final titleController = TextEditingController();
String titolo = '';
//late Widget display;
List<Widget> display = <Widget>[];
//int displayIndex = 1;
initialize:
#override
Widget build(BuildContext context) {
display.add(calculator());
//display = calculator();
and use it on body property:
body: display.first,
I get this error:
Exception has occurred.
_TypeError (type 'TabContainer' is not a subtype of type 'List' of 'function result')
Please note that TabContainer is the first Widget of calculator():
Widget calculator() => TabContainer(
selectedTextStyle: const TextStyle(
fontFamily: 'ThousandSunny',
This the entire code:
import 'package:cookedcalories/utils.dart';
import 'package:flutter/material.dart';
import 'package:convex_bottom_bar/convex_bottom_bar.dart';
import 'package:tab_container/tab_container.dart';
void main() {
runApp(const MyApp());
}
class MyApp extends StatelessWidget {
const MyApp({Key? key}) : super(key: key);
// This widget is the root of your application.
#override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Cooked Calories & Macros',
theme: ThemeData(
primarySwatch: Colors.pink,
),
home: const MyHomePage(title: 'Cooked Calories & Macros'),
);
}
}
class MyHomePage extends StatefulWidget {
const MyHomePage({Key? key, required this.title}) : super(key: key);
final String title;
#override
State<MyHomePage> createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
final titleController = TextEditingController();
String titolo = '';
//late Widget display;
List<Widget> display = <Widget>[];
//int displayIndex = 1;
#override
void initState() {
titleController.addListener(() => setState(() {}));
super.initState();
}
#override
Widget build(BuildContext context) {
display.add(calculator());
//display = calculator();
return Scaffold(
backgroundColor: Colors.yellow,
bottomNavigationBar: ConvexAppBar(
style: TabStyle.react,
items: const [
TabItem(icon: Icons.info_outline),
TabItem(icon: Icons.receipt_outlined),
TabItem(icon: Icons.calculate_outlined),
TabItem(icon: Icons.monetization_on_outlined),
TabItem(icon: Icons.settings_outlined),
],
initialActiveIndex: 1,
onTap: (int i) => print('click index=$i'),
),
appBar: AppBar(
title: Text(
widget.title,
style: const TextStyle(
fontFamily: 'ThousandSunny',
fontSize: 35,
),
),
),
body: display.first,
);
}
Widget calculator() => TabContainer(
selectedTextStyle: const TextStyle(
fontFamily: 'ThousandSunny',
fontSize: 35,
fontWeight: FontWeight.bold),
unselectedTextStyle: const TextStyle(
fontFamily: 'ThousandSunny',
fontSize: 35,
),
color: Colors.white,
radius: 50,
tabEdge: TabEdge.left,
tabs: const [
'A',
'B',
'C',
],
children: [
Align(
alignment: Alignment.topCenter,
child: SingleChildScrollView(
padding: const EdgeInsets.all(10),
child: Column(
mainAxisAlignment: MainAxisAlignment.spaceBetween,
children: [
Row(
children: [
Expanded(
child: Padding(
padding: const EdgeInsets.fromLTRB(5, 30, 0, 0),
child: createTitleField()),
),
const Padding(
padding: EdgeInsets.fromLTRB(10, 30, 5, 0),
child: Image(
width: 50,
height: 50,
image: AssetImage('assets/images/clean.png')),
),
],
),
],
)),
),
const Text('Child 2'),
const Text('Child 3'),
],
);
Widget createTitleField() => TextFormField(
style: const TextStyle(
fontFamily: 'ThousandSunny',
fontSize: 25,
),
controller: titleController,
validator: (value) {
if (value == null || value.trim().isEmpty) {
showSnackBar(
context,
"Attenzione: non hai inserito il Titolo dell'oggetto.",
Colors.pinkAccent.shade400);
return 'Inserisci il Titolo per questo oggetto';
} else if (value.trim().length < 3) {
showSnackBar(
context,
"Attenzione: Il Titolo deve contenere almeno 3 caratteri.",
Colors.pinkAccent.shade400);
return 'Lunghezza minima 3 caratteri';
} else if (value.trim().length > 30) {
showSnackBar(
context,
"Attenzione: Il Titolo non può essere più lungo di 30 caratteri.",
Colors.pinkAccent.shade400);
return 'Lunghezza massima 30 caratteri';
}
titolo = value;
return null;
},
decoration: InputDecoration(
border: const OutlineInputBorder(),
hintText: 'Nome Ricetta',
labelText: 'Nome Ricetta',
labelStyle: const TextStyle(
fontFamily: 'ThousandSunny',
fontSize: 30,
),
hintStyle: const TextStyle(
fontFamily: 'ThousandSunny',
fontSize: 25,
),
suffixIcon: titleController.text.isEmpty
? Container(
width: 0,
)
: IconButton(
onPressed: () => titleController.clear(),
icon: const Icon(Icons.close),
)),
keyboardType: TextInputType.text,
textInputAction: TextInputAction.next,
);
}

Answer 1

Try Stop project, run flutter pub get and start project again.