How to Create a NFC Reader and Writer Flutter Application

Last Updated : 25 Feb, 2025

NFC that stands for Near Field Communication, is a very short range wireless technology that allows us share small amount of data between devices. Through this technology we can share data between an NFC tag and an android device or between two android devices. A maximum of 4 cm distance is required to establish this connection. In this articles, we will be developing a basic application that involved communicating between an Android Device and a NFC Tag.

Prerequisites

NFC-Enabled Android Device - Your device must support NFC.
Android Studio or Visual Studio Code- Install Android Studio or Visual Studio Code in your System.
Basic Knowledge of Flutter & dart - We will be developing this app using the Flutter & Dart.
NFC Tag - You must have a NFC tag, sticker or a card for testing purposes.

Steps to Create a NFC Reader and Writer Android Application

Step 1: Create a New Project in Android Studio or Visual Studio Code.

To create a new project in Android Studio please refer to Creating a Simple Application in Flutter.

Step 2: In your flutter project open pubspec.yaml and under dependencies add the following packages:

dependencies:
   flutter:
         sdk: flutter
   nfc_manager: ^3.5.0

To know more about package refer : nfc_manager

Step 3: Adding Permissions in Manifest File

Navigate to android > app > src > main > AndroidManifest.xml and add the following permissions under the manifest tag.

<uses-permission android:name="android.permission.NFC"  />
<uses-feature android:name="android.hardware.nfc"  android:required ="true"  />

Step 3: Working with main.dart

main.dart include 3 primary functionalities to execute NFC in flutter application.

Check the device is compatible with NFC or Not
Read data using NFC
Write data using NFC

- Check the device is compatible with NFC or not.

Dart

 NfcManager.instance.isAvailable().then((isAvailable) {     if (isAvailable) {         print("availble"); // Start NFC session if available     } else {         print("unavailble"); // Show error message if NFC is not available       } });

- Read data using NFC

Dart

// Function to read NFC tag void _readNfcTag() {     //Start NFC session     NfcManager.instance.startSession(onDiscovered: (NfcTag tag) async {       Ndef? ndef = Ndef.from(tag);       if (ndef != null) {         // Read message from tag         NdefMessage? message = await ndef.read();          //Code to Store the fetched data from tag         ....       }       // Stop NFC session       NfcManager.instance.stopSession();      });   }

- Write data using NFC

Dart

void _writeNfcTag() {     // Start NFC session     NfcManager.instance.startSession(onDiscovered: (NfcTag tag) async {       // Example of writing data to the tag       Ndef? ndef = Ndef.from(tag);       if (ndef != null && ndef.isWritable) {         // Create NDEF message with input text         NdefMessage message = NdefMessage([           NdefRecord.createText(String_data),          ]);         // Write message to tag         await ndef.write(message);        }       // Stop NFC session       NfcManager.instance.stopSession();      }); }

The whole Application code for this is provided below:

main.dart:

Dart

import 'package:flutter/material.dart'; import 'package:nfc_manager/nfc_manager.dart';  void main() {        // Start the app   runApp(const MyApp());  }  class MyApp extends StatelessWidget {   const MyApp({super.key});    @override   Widget build(BuildContext context) {     return MaterialApp(       debugShowCheckedModeBanner: false, // Hide the debug banner       home: NfcScreen(), // Set the home screen to BitCoinTracker     );   } }  // Main class for the NFC screen class NfcScreen extends StatefulWidget {   @override   _NfcScreenState createState() => _NfcScreenState(); }  // State class for the NFC screen class _NfcScreenState extends State<NfcScreen> {   // Variable to store NFC data   String _nfcData = 'No data';       // Controller for text input   final TextEditingController _textController = TextEditingController();       @override   void initState() {     super.initState();          // Check if NFC is available     NfcManager.instance.isAvailable().then((isAvailable) {       if (isAvailable) {         // Start NFC session if available       }        else {         setState(() {                         // Update UI if NFC is not available            _nfcData = 'NFC is not available';          });       }     });   }    // Function to start NFC session   void _writeNfcTag() {            // Start NFC session     NfcManager.instance.startSession(onDiscovered: (NfcTag tag) async {              // Example of writing data to the tag       Ndef? ndef = Ndef.from(tag);              if (ndef != null && ndef.isWritable) {                  // Create NDEF message with input text         NdefMessage message = NdefMessage([           NdefRecord.createText(_textController.text),         ]);         try {           // Write message to tag           await ndef.write(message);           setState(() {               // Update UI on success               _nfcData = 'Write successful!';            });         } catch (e) {           setState(() {               // Update UI on failure               _nfcData = 'Write failed: $e';            });         }       }              // Stop NFC session       NfcManager.instance.stopSession();     });   }    // Function to read NFC tag   void _readNfcTag() {     NfcManager.instance.startSession(onDiscovered: (NfcTag tag) async {       Ndef? ndef = Ndef.from(tag);       if (ndef != null) {         // Read message from tag         NdefMessage? message = await ndef.read();                  setState(() {                        // Store payload in temp variable           var rawData = message.records.first.payload;                       // Convert payload to string           String textData = String.fromCharCodes(rawData);                       // Update UI with read data           _nfcData = textData.substring(3);          });       }              // Stop NFC session       NfcManager.instance.stopSession();     });   }    @override   Widget build(BuildContext context) {     return Scaffold(       appBar: AppBar(         title: Text('NFC Screen'), // App bar title       ),       body: Padding(         padding: const EdgeInsets.all(20),         child: Column(           mainAxisAlignment: MainAxisAlignment.center,           children: [             TextField(               controller: _textController,               decoration: InputDecoration(                 labelText: 'Enter data to write', // Input field label               ),             ),             ElevatedButton(               onPressed: _writeNfcTag,               child: Text('Write to NFC'), // Button to write to NFC             ),             ElevatedButton(               onPressed: _readNfcTag,               child: Text('Read from NFC'), // Button to read from NFC             ),             SizedBox(height: 20),             Text(_nfcData), // Display NFC data           ],         ),       ),     );   } }

Output:

Note : default NFC reader can pop-up in your screen. So, the solution is preventing default Android NFC reader.

Solution of the above Problem

If you get any uneven behavior of the app like opening a default pop-up in the middle of the process then to control that behavior add below code in android > app > src > main > kotlin > com > example > oyo > MainActivity.kt.

MainActivity.kt:

Kotlin

package com.example.yourapp import android.app.PendingIntent import android.content.Intent import android.nfc.NfcAdapter import io.flutter.embedding.android.FlutterActivity  class MainActivity: FlutterActivity() {      // This method is called when the     // activity is resumed     override fun onResume() {         super.onResume()                  // Create an intent to restart         // this activity         val intent = Intent(context, javaClass).addFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP)                  // Create a pending intent to be         // used by the NFC adapter         val pendingIntent = PendingIntent.getActivity(this, 0, intent, PendingIntent.FLAG_IMMUTABLE)                  // Enable NFC foreground dispatch         // to handle NFC tags when the app         // is in the foreground         NfcAdapter.getDefaultAdapter(context)?.enableForegroundDispatch(this, pendingIntent, null, null)     }      // This method is called when the     // activity is paused     override fun onPause() {         super.onPause()         // Disable NFC foreground dispatch         // when the app is not in the foreground         NfcAdapter.getDefaultAdapter(context)?.disableForegroundDispatch(this)     } }

For GitHub link for the repository for the application is refer to this link.

Creating a Simple Application in Flutter

vinaylaop3z

Improve

Article Tags :

How to Create a NFC Reader and Writer Flutter Application

Steps to Create a NFC Reader and Writer Android Application

Step 1: Create a New Project in Android Studio or Visual Studio Code.

Step 2: In your flutter project open pubspec.yaml and under dependencies add the following packages:

Step 3: Adding Permissions in Manifest File

Step 3: Working with main.dart

Solution of the above Problem

Similar Reads