Invalid constant value.dart(invalid_constant) - flutter

Question

in the bellow code I got the error on " controller: urlController," this line
var url;
final urlController = TextEditingController();
#override
void dispose() {
urlController.dispose();
super.dispose();
}
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
backgroundColor: const Color(0xff16352A),
title: const Text(
'Downloader',
style: TextStyle(color: Color(0xffEDAB24)),
),
),
body: Container(
padding: const EdgeInsets.all(20.0),
child: Column(
crossAxisAlignment: CrossAxisAlignment.center,
children: [
const SizedBox(height: 50.0),
const TextField(
controller: urlController,
decoration: InputDecoration(
border: OutlineInputBorder(),
labelText: 'Paste URL',
),
),
const SizedBox(height: 20.0),
Row(
mainAxisAlignment: MainAxisAlignment.spaceAround,
children: [
TextButton(
onPressed: () {},
child: const Text(
'Download',
style: TextStyle(fontSize: 30.0),
),
style: TextButton.styleFrom(
primary: Colors.white,
backgroundColor: const Color(0xff284635),
),
),
const SizedBox(width: 20.0),
TextButton(
onPressed: () {
setState(() {
url = urlController.text;
});
},
child: const Text(
'Clear',
style: TextStyle(fontSize: 30.0),
),
style: TextButton.styleFrom(
primary: Colors.white,
backgroundColor: const Color(0xff284635),
),
),
],
)
],
),
),
);
}
}

Answer 1

Just remove const value in front of TextField
TextField(
controller: urlController,
decoration: InputDecoration(
border: OutlineInputBorder(),
labelText: 'Paste URL',
),
)

Answer 2

Whenever you face Invalid constant value error, It sounds like you're using the const keyword but are not providing a constant value.
The fix is to remove the const keyword