Put method doesnt work in Flutter but perfectly ok in Postman

I tried an API endpoint with Postman and the Put Method works perfectly but In flutter, it doesn't update the field in textfromfield. tried every possible solution, A life-changing help

  void UpdateTask(int id, String a, String b) {
    var updateUrl =
        Uri.parse('https:........./api/update/${id}/');
    setState(() {
      widget.client.put(
        updateUrl,
        headers: <String, String>{
          'Content-Type': 'application/json; charset=UTF-8',
        },
        body: jsonEncode({
          "Title": a,
          "Desc": b,
        }),
      );
    });

    Navigator.pop(context);
  }

import 'package:flutter/material.dart';
import 'package:http/http.dart';
class UpdatePage extends StatefulWidget {
  final String title;
  final String Desc;
  final int idoftask;
  final Client client;

  const UpdatePage({
    super.key,
    required this.title,
    required this.Desc,
    required this.idoftask,
    required this.client,
  });

  @override
  State<UpdatePage> createState() => _UpdatePageState();
}

class _UpdatePageState extends State<UpdatePage> {
  TextEditingController taskEditingController = TextEditingController();
  TextEditingController desEditingController = TextEditingController();

  @override
  void initState() {
    taskEditingController.text = widget.title;
    desEditingController.text = widget.Desc;

    super.initState();
  }

  void UpdateTask(int id, String a, String b) {
    var updateUrl =
        Uri.parse('https://-------/api/update/${id}/');
    setState(() {
      widget.client.put(
        updateUrl,
        headers: <String, String>{
          'Content-Type': 'application/json; charset=UTF-8',
        },
        body: jsonEncode({
          "Title": a,
          "Desc": b,
        }),
      );
    });

    Navigator.pop(context);
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      backgroundColor: Colors.yellow[200],
      appBar: AppBar(
        title: const Text(
          'UPDATE THE TASK',
          style: TextStyle(color: Colors.brown),
        ),
        elevation: 0,
        centerTitle: true,
      ),
      body: Padding(
        padding: const EdgeInsets.symmetric(vertical: 18, horizontal: 25),
        child: Column(
          children: [
            TextFormField(
              controller: taskEditingController,
              decoration: InputDecoration(
                hintText: 'Task',
                hintStyle: TextStyle(color: Colors.grey),
              ),
            ),
            SizedBox(height: 15),
            TextFormField(
              controller: desEditingController,
              decoration: InputDecoration(
                hintText: 'Description',
                hintStyle: TextStyle(color: Colors.grey),
              ),
            ),
            SizedBox(height: 20),
            ElevatedButton(
              onPressed: (() => UpdateTask(
                    widget.idoftask,
                    taskEditingController.text,
                    desEditingController.text,
                  )),
              child: Text('Edit '),
            ),
          ],
        ),
      ),
    );
  }
}

changes based on other @Idriss and other SOF threads.Now working

Future<void> UpdateTask(int id, String a, String b) async {
var updateUrl =
    Uri.parse('https://todobackenda.herokuapp.com/api/update/${id}/');
final response = await widget.client.put(
  updateUrl,
  headers: <String, String>{
    'Content-Type': 'application/json; charset=UTF-8',
  },
  body: jsonEncode({
    "Title": a,
    "Desc": b,
  }),
);
if (response.statusCode == 200) {
  print(response.body);
  setState(() {});
}
Navigator.pop(context);

}

  onPressed: (() async {
                await UpdateTask(
                  widget.idoftask,
                  taskEditingController.text,
                  desEditingController.text,
                );
              }),`enter code here`

Add all other methods ( GET. DELETE. CREATE . )works but the PUT .. aLSO put method works in Postman. aLSO, put method works in Postman

You have to await your api call, after that you can reload your page.

SO you have to do :

  onPressed: (() async {
       var response = await widget.client.put(
       updateUrl,
       headers: <String, String>{
          'Content-Type': 'application/json; charset=UTF-8',
       },
       body: jsonEncode({
       "Title": a,
            "Desc": b,
       }),
    ); 
    if (response.statusCode == 200){
       setState(() { 
         ...
       }  
     }
  }