Firebase create, update, delete Flutter Updated

import 'package:cloud_firestore/cloud_firestore.dart';
import 'package:flutter/material.dart';

class DatabaseBasic extends StatefulWidget {
  const DatabaseBasic({Key? key}) : super(key: key);

  @override
  _DatabaseBasicState createState() => _DatabaseBasicState();
}

class _DatabaseBasicState extends State<DatabaseBasic> {

  TextEditingController name = TextEditingController();
  TextEditingController email = TextEditingController();

  create() async {
    try{
      await FirebaseFirestore.instance.collection('user').doc(email.text).set(
        {
          'name': name.text,
          'email': email.text
        }
      );
    } catch(e){
      print(e);
    }
  }

  update() async {
    try{
      await FirebaseFirestore.instance.collection('user').doc(email.text).update({
        'name': name.text
      });

    } catch(e){
      print(e);
    }
  }

  delete() async {
    try{
      await FirebaseFirestore.instance.collection('user').doc(email.text).delete();
    } catch(e){
      print(e);
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text("Database Basic"),
        centerTitle: true,
      ),
      body: Padding(
        padding: const EdgeInsets.all(10),
        child: Column(
          children: [
            _customTextField(name, "Name"),
            SizedBox(height: 10,),
            _customTextField(email, "Email"),
            SizedBox(height: 10,),
            Row(
              mainAxisAlignment: MainAxisAlignment.center,
              children: [
                _customElevatedButton(onPressed: create, btnLabel: "Create"),
                SizedBox(width: 10,),
                _customElevatedButton(onPressed: update, btnLabel: "Update"),
                SizedBox(width: 10,),
                _customElevatedButton(onPressed: delete, btnLabel: "Delete"),
              ],
            ),
            SizedBox(height: 10,),
            Expanded(
              child: Container(
                child: StreamBuilder(
                  stream: FirebaseFirestore.instance.collection('user').snapshots(),
                  builder: (context, AsyncSnapshot<QuerySnapshot> snapshot) {
                    if(snapshot.hasData){
                      return ListView.builder(
                        shrinkWrap: true,
                        physics: BouncingScrollPhysics(),
                        primary: true,
                        itemCount: snapshot.data!.docs.length,
                        itemBuilder: (context, index){
                          QueryDocumentSnapshot networkData = snapshot.data!.docs[index];
                          return Card(
                            child: ListTile(
                              onLongPress: (){
                                setState(() {
                                  name.text = networkData['name'];
                                  email.text = networkData['email'];
                                });
                              },
                              title: Text(networkData['name']),
                              subtitle: Text(networkData['email']),
                              trailing: IconButton(
                                onPressed: (){
                                  showDialog(
                                    context: context,
                                    builder: (context){
                                      return AlertDialog(
                                        title: Text("Confirm!!!"),
                                        content: Text("Are you sure you?"),
                                        actions: [
                                          ElevatedButton(
                                            onPressed: (){
                                              name.text = networkData['name'];
                                              email.text = networkData['email'];
                                              delete();
                                              name.clear();
                                              email.clear();
                                              Navigator.pop(context);
                                            },
                                            child: Text("Yes")),
                                          ElevatedButton(
                                            onPressed: (){
                                              Navigator.pop(context);
                                            },
                                            child: Text("No")),
                                        ],
                                      );
                                    }
                                  );
                                },
                                  icon: Icon(Icons.delete, color: Colors.red,),
                              ),
                              // leading: Text(networkData['test']),
                            ),
                          );
                        }
                      );
                    }
                    return const Center(child: CircularProgressIndicator());
                  }
                ),
              ),
            ),
          ],
        ),
      ),
    );
  }

  Widget _customTextField(TextEditingController controller, String label){
    return TextField(
      controller: controller,
      decoration: InputDecoration(
        label: Text(label),
        border: OutlineInputBorder(
            borderSide: BorderSide(color: Colors.red, width: 2),
            borderRadius: BorderRadius.circular(15)
        ),
        enabledBorder: OutlineInputBorder(
            borderSide: BorderSide(color: Colors.red, width: 2),
            borderRadius: BorderRadius.circular(15)
        ),
        focusedBorder: OutlineInputBorder(
            borderSide: BorderSide(color: Colors.red, width: 2),
            borderRadius: BorderRadius.circular(15)
        ),
      ),
    );
  }

  /// [onPressed] : Give the function that needs to call on pressing the button.
  ///
  /// [btnLabel] : Give the name of the Button.
  Widget _customElevatedButton({required VoidCallback? onPressed, required String btnLabel})  {
    return ElevatedButton(
      onPressed: (){
        onPressed!();
        setState(() {
          name.clear();
          email.clear();
        });
      },
      child: Text(btnLabel),
    );
  }
}