1.A value of type 'Future<dynamic>' can't be returned from the method 'showDilong' because it has a return type of 'Future<void> Function()?'.dart

err.dart

import 'package:flutter/material.dart';

class ScreenComment extends StatelessWidget {
  
  Future<void> Function()? showDilong(BuildContext context) {
    final TextEditingController _textFieldController = TextEditingController();

    return showDialog(
        context: context,
        builder: (context) {
          return AlertDialog(
            title: Text('TextField in Dialog'),
            content: TextField(
              onChanged: (value) {},
              controller: _textFieldController,
              decoration: InputDecoration(hintText: "Text Field in Dialog"),
            ),
          );
        });
  }

  void _showAlertDialog(BuildContext context) {
    showDialog(
      context: context,
      builder: (BuildContext context) {
        return AlertDialog(
          title: const Text('Alert Dialog Title'),
          content: const Text('This is the content of the alert dialog.'),
          actions: <Widget>[
            TextButton(
              child: const Text('Cancel'),
              onPressed: () {
                Navigator.of(context).pop();
              },
            ),
            TextButton(
              child: const Text('Confirm'),
              onPressed: () {
                // Handle the confirm action
              },
            ),
          ],
        );
      },
    );
  }

  @override
  Widget build(BuildContext context) {
    final List<String> listing = <String>[
      'Build My website(nginx + Front)',
      'Write the todo code(diesel + postgresql)',
      'cargo publish todo app'
    ];

    final len = listing.length;
    return Scaffold(
      appBar: AppBar(
        title: Text('Comment'),
      ),
      body: CustomScrollView(
        slivers: [
          SliverList(
            delegate: SliverChildBuilderDelegate(
              (context, index) => ListTile(title: Text('${listing[index]}')),
              childCount: len,
            ),
          ),
        ],
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: _showAlertDialog(context),
        child: const Icon(Icons.add),
      ),
    );
  }
}