void _showConfirmDialog(BuildContext context) {
  showDialog(
    context: context,
    builder: (context) => AlertDialog(
      title: Text("ยืนยันการลบ"),
      content: Text("คุณแน่ใจหรือไม่ว่าจะลบข้อมูลนี้?"),
      actions: [
        TextButton(onPressed: () => Navigator.pop(context), child: Text("ยกเลิก")),
        ElevatedButton(onPressed: () => Navigator.pop(context), child: Text("ตกลง"))
      ],
    ),
  );
}

void _showSnackBar(BuildContext context, String message) {
  ScaffoldMessenger.of(context).showSnackBar(
    SnackBar(
      content: Text(message),
      duration: Duration(seconds: 2),
    ),
  );
}

import 'package:flutter/material.dart';

void main() => runApp(MyApp());

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(home: DialogDemo());
  }
}

class DialogDemo extends StatelessWidget {
  void _showConfirmDialog(BuildContext context) {
    showDialog(
      context: context,
      builder: (context) => AlertDialog(
        title: Text("ยืนยัน"),
        content: Text("คุณต้องการลบข้อมูลหรือไม่?"),
        actions: [
          TextButton(onPressed: () => Navigator.pop(context), child: Text("ยกเลิก")),
          ElevatedButton(
            onPressed: () {
              Navigator.pop(context);
              _showSnackBar(context, "ลบข้อมูลแล้ว");
            },
            child: Text("ตกลง"),
          )
        ],
      ),
    );
  }

  void _showSnackBar(BuildContext context, String message) {
    ScaffoldMessenger.of(context).showSnackBar(
      SnackBar(content: Text(message), duration: Duration(seconds: 2)),
    );
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text("Dialog & SnackBar")),
      body: Center(
        child: ElevatedButton(
          onPressed: () => _showConfirmDialog(context),
          child: Text("แสดงการแจ้งเตือน"),
        ),
      ),
    );
  }
}