反应原生：app：transformClassesWithDexForDebug失败

Question

Suddenly I can no longer build a react native app. The task, mentioned in the question title fails with following message:

* What went wrong:
Execution failed for task ':app:transformClassesWithDexForDebug'.
> com.android.build.api.transform.TransformException: com.android.ide.common.process.ProcessException: java.util.concurrent.ExecutionException: com.android.dex.DexException: Multiple dex files define Lcom/google/android/gms/internal/zzmu;

My android/build.gradle :

// Top-level build file where you can add configuration options common to all sub-projects/modules.

buildscript {
    repositories {
        jcenter()
    }
dependencies {
    classpath 'com.android.tools.build:gradle:2.1.2'
    classpath 'com.google.gms:google-services:3.0.0'

    // NOTE: Do not place your application dependencies here; they belong
    // in the individual module build.gradle files
    }
}

allprojects {
    repositories {
        mavenLocal()
        jcenter()
        maven {
        // All of React Native (JS, Obj-C sources, Android binaries) is installed from npm
        url "$rootDir/../node_modules/react-native/android"
        }
    }
}

And dependencies section from android/app/build.gradle :

dependencies {
    compile project(':react-native-keychain')
    compile project(':react-native-fbsdk')
    compile project(':react-native-randombytes')
    compile project(':react-native-barcodescanner')
    compile project(':react-native-camera')
    compile project(':rn-splash-screen')
    compile project(':react-native-code-push')
    compile project(':react-native-vector-icons')
    compile fileTree(dir: "libs", include: ["*.jar"])
    compile "com.android.support:appcompat-v7:23.0.1"
    compile "com.facebook.react:react-native:+"  // From node_modules
    compile(project(":react-native-google-signin")){
      exclude group: "com.google.android.gms"
    }
    compile 'com.google.firebase:firebase-core:9.4.0'
    compile 'com.google.android.gms:play-services-auth:9.4.0'
    compile project(':react-native-vector-icons')
    compile project(':react-native-code-push')
    compile project(':react-native-onesignal')
}

I've heard that it occurs due to conflicts (eg google play services declared twice, or declared as a particular service in one place and as a whole in another place) But can't figure out what the problem is. What's wrong here and how can I fix it?

Answer 1

My (limited) understanding of Android tells me that you are including seperate dependencies that share a method name in some way or another. I've found these errors to typically point to a version mismatch in my dependency tree - in this case it looks like you have multiple projects depending on com.google.android.gms:play-services-auth .

The conflicts you've heard of seem to be problem... exclude group may not be working how you intend.

Take a look inside node_modules/react-native-google-signin/android/build.gradle and compare the version of play-services-auth it depends on against the play-services-auth in your project's app/build.gradle . Considering your dependency list points at version 9.4.0 you can try setting the react-native-google-signin dependency version to match, or vice-versa.

dependencies {
    compile "com.google.android.gms:play-services-auth:9.4.0"
    compile "com.facebook.react:react-native:+"
}

Answer 2

clean gradle then build again.

cd android then ./gradlew clean