import 'package:flutter/material.dart'; class MarinePreSampling extends StatefulWidget { @override State createState() => _MarinePreSamplingState(); } class _MarinePreSamplingState extends State { final _formKey = GlobalKey(); String site = ''; String weather = ''; String tide = ''; @override Widget build(BuildContext context) { return Scaffold( appBar: AppBar(title: Text("Marine Pre-Sampling")), body: Padding( padding: const EdgeInsets.all(24), child: Form( key: _formKey, child: ListView( children: [ Text("Enter Pre-Sampling Conditions", style: TextStyle(fontSize: 18, fontWeight: FontWeight.bold)), SizedBox(height: 24), TextFormField( decoration: InputDecoration(labelText: "Site"), onChanged: (val) => site = val, validator: (val) => val == null || val.isEmpty ? "Required" : null, ), SizedBox(height: 16), TextFormField( decoration: InputDecoration(labelText: "Weather"), onChanged: (val) => weather = val, validator: (val) => val == null || val.isEmpty ? "Required" : null, ), SizedBox(height: 16), TextFormField( decoration: InputDecoration(labelText: "Tide Condition"), onChanged: (val) => tide = val, validator: (val) => val == null || val.isEmpty ? "Required" : null, ), SizedBox(height: 24), ElevatedButton( onPressed: () { if (_formKey.currentState!.validate()) { ScaffoldMessenger.of(context).showSnackBar( SnackBar(content: Text("Pre-sampling data submitted")), ); } }, child: Text("Submit"), ), ], ), ), ), ); } }