Barcode Scanner

A flutter plugin for scanning 2D barcodes and QR codes.

This provides a simple wrapper for two commonly used iOS and Android libraries:

iOS: https://github.com/mikebuss/MTBBarcodeScanner

Android: https://github.com/dm77/barcodescanner

Features

• Scan 2D barcodes
• Scan QR codes
• Control the flash while scanning
• Permission handling

Getting Started

Android

For Android, you must do the following before you can use the plugin:

• Add the camera permission to your AndroidManifest.xml

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

• This plugin is written in Kotlin. Therefore, you need to add Kotlin support to your project. See installing the Kotlin plugin.

Edit your project-level build.gradle file to look like this:

buildscript {
    ext.kotlin_version = '1.3.61'
    // ...
    dependencies {
        // ...
        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
    }
}
// ...

Edit your app-level build.gradle file to look like this:

apply plugin: 'kotlin-android'
// ...
dependencies {
    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
    // ...
}

Now you can depend on the barcode_scan plugin in your pubspec.yaml file:

dependencies:
    # ...
    barcode_scan: any

Click "Packages get" in Android Studio or run flutter packages get in your project folder.

iOS

To use on iOS, you must add the the camera usage description to your Info.plist

<dict>
    <!-- ... -->
    <key>NSCameraUsageDescription</key>
    <string>Camera permission is required for barcode scanning.</string>
    <!-- ... -->
</dict>

Usage

import 'package:barcode_scan/barcode_scan.dart';

void main() async {
  var result = await BarcodeScanner.scan();
  
  print(result.type); // The result type (barcode, cancelled, failed)
  print(result.rawContent); // The barcode content
  print(result.format); // The barcode format (as enum)
  print(result.formatNote); // If a unknown format was scanned this field contains a note
}

Advanced usage

You can pass options to the scan method:

import 'package:barcode_scan/barcode_scan.dart';

void main() async {
  
  var options = ScanOptions(
    // set the options
  );

  var result = await BarcodeScanner.scan(options: options);
  
  // ...
}

Supported options

Option	Type	Description	Supported by
strings.cancel	String	The cancel button text on iOS	iOS only
strings.flash_on	String	The flash on button text	iOS + Android
strings.flash_off	String	The flash off button text	iOS + Android
restrictFormat	BarcodeFormat[]	Restrict the formats which are recognized	iOS + Android
useCamera	int	The index of the camera which is used for scanning (See BarcodeScanner.numberOfCameras)	iOS + Android
autoEnableFlash	bool	Enable the flash when start scanning	iOS + Android
android.aspectTolerance	double	Enable auto focus on Android	Android only
android.useAutoFocus	bool	Set aspect ratio tolerance level used in calculating the optimal Camera preview size	Android only

Development setup

Setup protobuf

Mac:

$ brew install protobuf
$ brew install swift-protobuf

Windows / Linux: https://github.com/protocolbuffers/protobuf#protocol-compiler-installation

Activate the protobuf dart plugin: $ pub global activate protoc_plugin

Install theProtobuf Support plugin for IDEA / Android Studio or vscode-proto3 for VS Code

If you changed the protos.proto you've to execute the ./generate_proto.sh to update the dart / swift sources

Common problems

Android "Could not find org.jetbrains.kotlin:kotlin-stdlib-jre..."

Change org.jetbrains.kotlin:kotlin-stdlib-jre to org.jetbrains.kotlin:kotlin-stdlib-jdk (StackOverflow)