How to build a QR code generator and reader in FlutterFlow?

 

Building a QR Code Generator and Reader in FlutterFlow

 

Creating a QR code generator and reader involves understanding FlutterFlow's capabilities and integrating custom Flutter code for the functionality. Below is a comprehensive guide detailing the steps involved.

 

Prerequisites

 

• Have a FlutterFlow account with a project ready for QR code integration.
• Understand Flutter widgets and FlutterFlow's visual application builder.
• Basic knowledge of using external packages in a Flutter project.

 

Setting Up Your FlutterFlow Project

 

• Log into your FlutterFlow account and open your project where you want to implement the QR code functionality.
• Ensure that your project is set to the latest version of Flutter to use the most updated libraries and functions efficiently.

 

QR Code Generation

 

• Identify the part of your application where users will generate QR codes.
• Add a text input in the widget tree to allow users to enter information that will be converted into a QR code.
• Use the Custom Actions feature to write custom Dart code that leverages a QR code generation package like qr\_flutter.

 

Integrating QR Code Generation Package

 

• Within the FlutterFlow custom actions, add necessary dependencies in your pubspec.yaml file for the qr\_flutter package:

      dependencies:
        qr\_flutter: ^4.0.0
      

• Create a Custom Widget that utilizes the package to generate a QR code from user input:

      import 'package:flutter/material.dart';
      import 'package:qr_flutter/qr_flutter.dart';
  
  class QRCodeGenerator extends StatelessWidget {
    final String data;
    QRCodeGenerator({required this.data});
  
    @override
    Widget build(BuildContext context) {
      return QrImage(
        data: data,
        version: QrVersions.auto,
        size: 200.0,
      );
    }
  }
  </pre>
  
    

• Integrate this widget into your FlutterFlow UI where needed to display the QR code and bind it to the user input.

 

QR Code Reader

 

• Determine the part of your application where you need to scan QR codes.
• Add a button in the FlutterFlow UI that will trigger a QR code scanning feature.

 

Integrating QR Code Scanning Package

 

• Utilize the qr_code_scanner package for scanning functionality. Add it to your pubspec.yaml:

      dependencies:
        qr_code_scanner: ^0.4.0
      

• Create a custom widget with camera permissions asking functionality and scanning ability:

      import 'package:flutter/material.dart';
      import 'package:qr_code_scanner/qr_code_scanner.dart';
  
  class QRCodeScanner extends StatefulWidget {
    @override
    _QRCodeScannerState createState() => _QRCodeScannerState();
  }
  
  class \_QRCodeScannerState extends State<QRCodeScanner> {
    final GlobalKey qrKey = GlobalKey(debugLabel: 'QR');
    QRViewController? controller;
  
    @override
    Widget build(BuildContext context) {
      return Scaffold(
        body: Column(
          children: [
            Expanded(
              child: QRView(
                key: qrKey,
                onQRViewCreated: \_onQRViewCreated,
              ),
            ),
          ],
        ),
      );
    }
  
    void \_onQRViewCreated(QRViewController controller) {
      this.controller = controller;
      controller.scannedDataStream.listen((scanData) {
        print(scanData); 
        // Handle scanned data.
      });
    }
  
    @override
    void dispose() {
      controller?.dispose();
      super.dispose();
    }
  }
  </pre>
  
    

• Link this widget to your FlutterFlow interface, ensuring the button triggers the scanner view.

 

Configuring Permissions

 

• Ensure your app has the necessary camera permissions. For Android, include the following in AndroidManifest.xml:

      <uses-permission android:name="android.permission.CAMERA" />
      

• For iOS, edit your Info.plist to add camera usage description:

      <key>NSCameraUsageDescription</key>
      <string>We need camera access to scan QR codes.</string>
      

 

Testing and Validation

 

• Ensure that all functionalities for generating and scanning QR codes work as expected in FlutterFlow's preview mode.
• Test on physical devices to validate camera and scanning functionalities.
• Debug any issues using Flutter's integrated debugging tools and console outputs.

 

Deploying Your QR Code Functional App

 

• After successful testing, prepare your app for deployment by ensuring all custom functions and packages are correctly integrated.
• Check for compatibility across various devices and platform orientations to ensure a smooth user experience.

 

By following this guide, you should be able to implement robust QR code generation and reading functionalities in your FlutterFlow app, enabling a versatile interaction avenue for your users.