Ionic项目构建报错：Google ZXing相关类重复冲突

问题描述 #

构建Ionic项目时出现重复类错误，具体错误信息如下：

Duplicate class com.google.zxing.qrcode.encoder.Encoder$1 found in modules jetified-barcodescanner-release-2.1.5-runtime (:barcodescanner-release-2.1.5:) and jetified-core-3.4.0 (com.google.zxing:core:3.4.0)
Duplicate class com.google.zxing.qrcode.encoder.MaskUtil found in modules jetified-barcodescanner-release-2.1.5-runtime (:barcodescanner-release-2.1.5:) and jetified-core-3.4.0 (com.google.zxing:core:3.4.0)
Duplicate class com.google.zxing.qrcode.encoder.MatrixUtil found in modules jetified-barcodescanner-release-2.1.5-runtime (:barcodescanner-release-2.1.5:) and jetified-core-3.4.0 (com.google.zxing:core:3.4.0)
Duplicate class com.google.zxing.qrcode.encoder.QRCode found in modules jetified-barcodescanner-release-2.1.5-runtime (:barcodescanner-release-2.1.5:) and jetified-core-3.4.0 (com.google.zxing:core:3.4.0)

中文翻译 #

在模块jetified-barcodescanner-release-2.1.5-runtime（:barcodescanner-release-2.1.5:）和jetified-core-3.4.0（com.google.zxing:core:3.4.0）中发现重复类com.google.zxing.qrcode.encoder.Encoder$1
在模块jetified-barcodescanner-release-2.1.5-runtime（:barcodescanner-release-2.1.5:）和jetified-core-3.4.0（com.google.zxing:core:3.4.0）中发现重复类com.google.zxing.qrcode.encoder.MaskUtil
在模块jetified-barcodescanner-release-2.1.5-runtime（:barcodescanner-release-2.1.5:）和jetified-core-3.4.0（com.google.zxing:core:3.4.0）中发现重复类com.google.zxing.qrcode.encoder.MatrixUtil
在模块jetified-barcodescanner-release-2.1.5-runtime（:barcodescanner-release-2.1.5:）和jetified-core-3.4.0（com.google.zxing:core:3.4.0）中发现重复类com.google.zxing.qrcode.encoder.QRCode

解决方案 #

这个问题是因为项目同时引入了barcodescanner插件和com.google.zxing:core依赖，两者包含相同的Zxing编码类，导致冲突，可通过以下方法解决：

• 排除重复依赖：在项目的build.gradle文件中，给barcodescanner依赖添加排除规则，移除其自带的Zxing核心模块，保留单独引入的com.google.zxing:core：

dependencies {
    // 其他依赖...
    implementation('com.google.zxing:core:3.4.0')
    implementation(':barcodescanner-release-2.1.5:') {
        exclude group: 'com.google.zxing', module: 'core'
    }
}

• 统一依赖版本：如果不需要单独引入com.google.zxing:core，直接移除该依赖，使用barcodescanner插件自带的版本即可。

• 更新插件版本：尝试更新barcodescanner插件到最新版，新版本可能已修复依赖冲突问题，执行以下命令更新：

ionic cordova plugin update phonegap-plugin-barcodescanner
npm update @ionic-native/barcode-scanner

内容的提问来源于stack exchange，提问作者Ahmadou Adiawiakoye