how to input a string to textfield - flutter

Question

Is it possible that the last String from a list can be input automatically to a TextField?
The list is empty for first few seconds and it is changing. It is also initialize after build context.
If yes please provide a code because I am new to flutter.
I know how to change the text from a textfield by using TextEditingController.
final TextEditingController _controller = TextEditingController();
TextField(controller: _controller)
ElevatedButton(
onPressed: () {
const newText = 'Hello World';
final updatedText = _controller.text + newText;
_controller.value = _controller.value.copyWith(
text: updatedText,
selection: TextSelection.collapsed(offset: updatedText.length),
);
},
)
but it has a button, how can I automate this?

Answer 1

Yes you can do this by TextEditingController... Let's have a code example where you have a List of String.... e.g
import 'package:flutter/material.dart';
void main() {
runApp(const MyApp());
}
class MyApp extends StatefulWidget {
const MyApp({Key? key}) : super(key: key);
#override
State<MyApp> createState() => _MyAppState();
}
class _MyAppState extends State<MyApp> {
late TextEditingController _textEditingController;
final List<String> _exampleList = [];
#override
void initState() {
Future.delayed(
const Duration(seconds: 2),
() {
if (mounted) {
setState(() {
_exampleList.add("apple");
_textEditingController = TextEditingController(text: _exampleList.last);
});
}
},
);
_textEditingController = TextEditingController(text: "Loading ...");
super.initState();
}
#override
void dispose() {
_textEditingController.dispose();
super.dispose();
}
#override
Widget build(BuildContext context) {
return MaterialApp(
debugShowCheckedModeBanner: false,
home: Scaffold(
body: Center(
child: TextFormField(
enabled: _exampleList.isNotEmpty,
controller: _textEditingController,
),
),
),
);
}
}
here is the result... this is just a simple explanation of how you can show last item of list in textfield