what's Textfield and How to create TextField in Flutter ?

A TextField or TextBox

is an input element which holds the alphanumeric data, such as name, password, address, etc. It is a GUI control element that enables the user to enter text information using a programmable code. It can be of a single-line text field (when only one line of information is required) or multiple-line text field (when more than one line of information is required). TextField in Flutter is the most commonly used text input widget that allows users to collect inputs from the keyboard into an app. We can use the TextField widget in building forms, sending messages, creating search experiences, and many more. By default, Flutter decorated the TextField with an underline.

Example:

import 'package:flutter/material.dart';  
  
void main() {  
  runApp(MaterialApp( home: MyApp(),));  
}  
  
class MyApp extends StatefulWidget {  
  @override  
  _State createState() => _State();  
}  
  
class _State extends State<MyApp> {  
  @override  
  Widget build(BuildContext context) {  
    return Scaffold(  
        appBar: AppBar(  
          title: Text('Flutter TextField Example'),  
        ),  
        body: Padding(  
            padding: EdgeInsets.all(15),  
            child: Column(  
              children: <Widget>[  
                Padding(  
                  padding: EdgeInsets.all(15),  
                  child: TextField(  
                    decoration: InputDecoration(  
                      border: OutlineInputBorder(),  
                      labelText: 'User Name',  
                      hintText: 'Enter Your Name',  
                    ),  
                  ),  
                ),  
                Padding(  
                  padding: EdgeInsets.all(15),  
                  child: TextField(  
                    obscureText: true,  
                    decoration: InputDecoration(  
                      border: OutlineInputBorder(),  
                      labelText: 'Password',  
                      hintText: 'Enter Password',  
                    ),  
                  ),  
                ),  
                RaisedButton(  
                  textColor: Colors.white,  
                  color: Colors.blue,  
                  child: Text('Sign In'),  
                  onPressed: (){},  
                )  
              ],  
            )  
        )  
    );  
  }  
}