Learn How to Create a Flutter Barcode Scanner with Flutter Barcode Scanner Package

Table of Contents:

I. Introduction II. Installing the Flutter Barcode Scanner Package III. Adding Required Permissions for iOS Devices IV. Creating a Builder Widget V. Scanning Barcode A. Start Barcode Scan B. Start QR Scan C. Start Barcode Scan Stream VI. Handling Scan Results VII. Conclusion

📱 How to Create a Barcode Scanner in Flutter Using Flutter Barcode Scanner Package

Have you ever wondered how to create a barcode scanner in Flutter? Look no further! In this Tutorial, I will guide you through the process of building a barcode scanner in Flutter using the Flutter Barcode Scanner Package. Let's get started!

I. Introduction

Barcode scanning has become an essential feature in many mobile apps, enabling users to quickly and efficiently scan barcodes for various purposes. With Flutter, you can easily integrate barcode scanning functionality into your app using the Flutter Barcode Scanner package.

II. Installing the Flutter Barcode Scanner Package

Before we begin, we need to install the Flutter Barcode Scanner package. To do this, follow these steps:

1. Open your pubspec.yaml file.
2. Add the following line under the dependencies section:

dependencies:
  flutter_barcode_scanner: ^x.x.x

Make sure to replace ^x.x.x with the latest version of the package. Save the file and run flutter pub get to install the package.

III. Adding Required Permissions for iOS Devices

To ensure that our app can run on iOS devices, we need to add the required permissions. Follow these steps:

1. Open the Info.plist file in your iOS project.
2. Add the following lines inside the <Dict> tag:

<key>NSCameraUsageDescription</key>
<string>Enable camera access to scan barcodes</string>

IV. Creating a Builder Widget

To lay out our UI, we will create a builder widget. This widget will return a container with the alignment set to center and a child set to a flex widget. Within the flex widget, we will create three buttons for scanning barcodes.

Container(
  alignment: Alignment.center,
  child: Flex(
    direction: Axis.vertical,
    mainAxisAlignment: MainAxisAlignment.center,
    children: [
      ElevatedButton(
        onPressed: () {
          // Scan barcode logic
        },
        child: Text("Start Barcode Scan"),
      ),
      ElevatedButton(
        onPressed: () {
          // Scan QR logic
        },
        child: Text("Start QR Scan"),
      ),
      ElevatedButton(
        onPressed: () {
          // Scan barcode stream logic
        },
        child: Text("Start Barcode Scan Stream"),
      ),
    ],
  ),
),

V. Scanning Barcode

To scan a barcode, we will implement different functions for different scan modes. Let's look at each of them:

A. Start Barcode Scan

To start the barcode scan, we will create an elevated button with the text "Start Barcode Scan". When the button is pressed, the scanBarcodeNormal function will be triggered. This function returns a Future void and uses the async keyword to wait for the scan results.

ElevatedButton(
  onPressed: () async {
    await scanBarcodeNormal();
  },
  child: Text("Start Barcode Scan"),
),

B. Start QR Scan

Similar to the barcode scan, we will create an elevated button with the text "Start QR Scan". When pressed, the scanQR function will be triggered. The difference here is that we set the scan mode to "QR" instead of "Barcode".

ElevatedButton(
  onPressed: () async {
    await scanQR();
  },
  child: Text("Start QR Scan"),
),

C. Start Barcode Scan Stream

In some cases, we may want to continuously scan barcodes without immediately displaying the results. This can be achieved using the startBarcodeScanStream function. Here, we listen to a stream from the getBarcodeStreamReceiver function provided by the Flutter Barcode Scanner package. The function accepts the same properties as the previous scan functions.

ElevatedButton(
  onPressed: () async {
    await startBarcodeScanStream();
  },
  child: Text("Start Barcode Scan Stream"),
),

VI. Handling Scan Results

After scanning a barcode, we need to handle the scan results. We can update a text widget to display the scan results. This can be done by wrapping the scanning logic in a try-catch block and checking if the widget is still in the tree. If so, we update the value of the barcodeScanResult variable with the result of the scanBarcode function.

try {
  if (mounted) {
    setState(() {
      barcodeScanResult = await scanBarcode(
        lineColor: Colors.red, // Customize line color
        cancelButtonText: "Cancel", // Customize cancel button text
        showFlashIcon: true, // Show flash icon
        scanMode: ScanMode.DEFAULT, // Set scan mode (QR, Barcode, or Default)
      );
    });
  }
} on PlatformException catch (e) {
  // Handle platform exceptions
}

VII. Conclusion

In this tutorial, we have learned how to create a barcode scanner in Flutter using the Flutter Barcode Scanner package. We covered the installation process, adding required permissions for iOS devices, creating a builder widget, and implementing different scan modes. Now you can easily integrate barcode scanning functionality into your Flutter app.

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Now go ahead and enhance your app with the power of barcode scanning!

Highlights:

• Learn how to create a barcode scanner in Flutter using the Flutter Barcode Scanner package.
• Install the Flutter Barcode Scanner package and add the required permissions for iOS devices.
• Create a builder widget for laying out the UI.
• Implement different scan modes for scanning barcodes and QR codes.
• Handle scan results and display them in your app.
• Enhance your Flutter skills with the 12-week Flutter training on HeyPlatter.com.

FAQ

Q: How do I install the Flutter Barcode Scanner package? A: To install the Flutter Barcode Scanner package, add the following line to your pubspec.yaml file and run flutter pub get:

dependencies:
  flutter_barcode_scanner: ^x.x.x

Q: Can I customize the appearance of the barcode scanner? A: Yes, you can customize the line color, cancel button text, show or hide the flash icon, and choose the scan mode (QR, barcode, or default).

Q: How can I continuously scan barcodes without displaying the results immediately? A: You can use the startBarcodeScanStream function, which continuously scans barcodes and provides a stream of scan results.

Q: How can I handle exceptions while scanning barcodes? A: Wrap the scanning logic in a try-catch block and handle any platform exceptions that may occur.