Firebase Full

import 'package:cloud_firestore/cloud_firestore.dart';
import 'package:firebaser/student.dart';
import 'package:flutter/material.dart';
import 'package:firebase_core/firebase_core.dart';
import 'package:firebaser/firebase_options.dart';

void main() async {
  WidgetsFlutterBinding.ensureInitialized();
  await Firebase.initializeApp(
    options: DefaultFirebaseOptions.currentPlatform,
  );

  runApp(MaterialApp(
    theme: ThemeData(
      brightness: Brightness.light,
      primaryColor: Colors.blue,
      colorScheme: ColorScheme.fromSwatch().copyWith(secondary: Colors.cyan),
    ),
    home: const MyApp(),
  ));
}

class MyApp extends StatefulWidget {
  const MyApp({super.key});

  @override
  State<MyApp> createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {
  TextEditingController ct1 = TextEditingController();
  TextEditingController ct2 = TextEditingController();
  TextEditingController ct3 = TextEditingController();
  TextEditingController ct4 = TextEditingController();
  CollectionReference cref = FirebaseFirestore.instance.collection("Students");

  void enterData(TextEditingController ct1, TextEditingController ct2,
      TextEditingController ct3, TextEditingController ct4) {
    String n = ct1.text;
    String i = ct2.text;
    String c = ct3.text;
    double g = double.parse(ct4.text);

    Map<String, dynamic> map = {
      "Name": n,
      "ID": i,
      "Course": c,
      "GPA": g,
    };

    cref.doc(i).set(map);
  }

  void getData(TextEditingController ct1, TextEditingController ct2,
      TextEditingController ct3, TextEditingController ct4) async {
    final element = await cref.doc(ct2.text).get();
    ct1.text = element["Name"];
    ct2.text = element["ID"].toString();
    ct3.text = element["Course"];
    ct4.text = element["GPA"].toString();
  }

  void updateData(TextEditingController ct1, TextEditingController ct2,
      TextEditingController ct3, TextEditingController ct4) async {
    String n = ct1.text;
    String i = ct2.text;
    String c = ct3.text;
    double g = double.parse(ct4.text);

    Map<String, dynamic> map = {
      "Name": n,
      "ID": i,
      "Course": c,
      "GPA": g,
    };

    cref.doc(i).set(map);
  }

  void deleteData(TextEditingController ct1, TextEditingController ct2,
      TextEditingController ct3, TextEditingController ct4) async {
    await cref.doc(ct2.text).delete();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text("Airbase inc."),
      ),
      body: Column(
        children: <Widget>[
          Padding(
            padding: const EdgeInsets.all(8.0),
            child: TextFormField(
              controller: ct1,
              decoration: const InputDecoration(
                  labelText: "Student Name",
                  fillColor: Colors.white,
                  focusedBorder: OutlineInputBorder(
                      borderSide: BorderSide(color: Colors.blue, width: 2.0))),
              onChanged: (String str) {},
            ),
          ),
          Padding(
            padding: const EdgeInsets.all(8.0),
            child: TextFormField(
              controller: ct2,
              decoration: const InputDecoration(
                  labelText: "Student ID",
                  fillColor: Colors.white,
                  focusedBorder: OutlineInputBorder(
                      borderSide: BorderSide(color: Colors.blue, width: 2.0))),
              onChanged: (String str) {},
            ),
          ), //
          Padding(
            padding: const EdgeInsets.all(8.0),
            child: TextFormField(
              controller: ct3,
              decoration: const InputDecoration(
                  labelText: "Course",
                  fillColor: Colors.white,
                  focusedBorder: OutlineInputBorder(
                      borderSide: BorderSide(color: Colors.blue, width: 2.0))),
              onChanged: (String str) {},
            ),
          ),
          Padding(
            padding: const EdgeInsets.all(8.0),
            child: TextFormField(
              controller: ct4,
              decoration: const InputDecoration(
                  labelText: "GPA",
                  fillColor: Colors.white,
                  focusedBorder: OutlineInputBorder(
                      borderSide: BorderSide(color: Colors.blue, width: 2.0))),
              onChanged: (String str) {},
            ),
          ), //
          Row(
            mainAxisAlignment: MainAxisAlignment.spaceAround,
            children: <Widget>[
              ElevatedButton(
                onPressed: () {
                  setState(() {
                    getData(ct1, ct2, ct3, ct4);
                  });
                },
                child: const Text("Read"),
              ),
              ElevatedButton(
                onPressed: () {
                  enterData(ct1, ct2, ct3, ct4);
                },
                child: const Text("Create"),
              ),
              ElevatedButton(
                onPressed: () {
                  updateData(ct1, ct2, ct3, ct4);
                },
                child: const Text("Update"),
              ),
              ElevatedButton(
                onPressed: () {
                  // enterData(ct1, ct2, ct3, ct4);
                  deleteData(ct1, ct2, ct3, ct4);
                },
                child: const Text("Delete"),
              ),
            ],
          )
        ],
      ),
    );
  }
}