我尝试过 Google 的 Flutter Firebase 代码实验室。按照他们的建议添加了依赖项，但是当我将 apply plugin: 'com.google.gms.google-services' 行添加到我的 app/build.gradle 我的应用程序时停止编译并出现以下错误:
Dex: Error converting bytecode to dex:
Cause: com.android.dex.DexException: Multiple dex files define Lcom/google/android/gms/internal/zzcaw;
UNEXPECTED TOP-LEVEL EXCEPTION:
com.android.dex.DexException: Multiple dex files define Lcom/google/android/gms/internal/zzcaw;
com.android.dex.DexException: Multiple dex files define Lcom/google/android/gms/internal/zzcaw;
at com.android.dx.merge.DexMerger.readSortableTypes(DexMerger.java:661)
at com.android.dx.merge.DexMerger.getSortedTypes(DexMerger.java:616)
at com.android.dx.merge.DexMerger.mergeClassDefs(DexMerger.java:598)
at com.android.dx.merge.DexMerger.mergeDexes(DexMerger.java:171)
at com.android.dx.merge.DexMerger.merge(DexMerger.java:198)
at com.android.builder.dexing.DexArchiveMergerCallable.call(DexArchiveMergerCallable.java:61)
at com.android.builder.dexing.DexArchiveMergerCallable.call(DexArchiveMergerCallable.java:36)
at java.util.concurrent.ForkJoinTask$AdaptedCallable.exec(ForkJoinTask.java:1424)
at java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:289)
at java.util.concurrent.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1056)
at java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1692)
at java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:157)
FAILURE: Build failed with an exception.
* What went wrong:
Execution failed for task ':app:transformDexArchiveWithDexMergerForDebug'.
> com.android.build.api.transform.TransformException: com.android.dex.DexException: Multiple dex files define Lcom/google/android/gms/internal/zzcaw;
根据我对其他类似线程的研究，这个异常意味着某个东西定义了不止一次，但我很难识别那个东西，因为异常中的 zzcaw 部分每次都不同。
我的应用是一个空的新项目，除了 Codelab 建议的依赖项外，没有其他依赖项。还有一个线程提到我需要更新 Google Play 工具，但 SDK 管理器说我没有任何更新。我也试过更改 google-services 包的版本，项目开始构建版本 <=2.2.0 但应用程序不会启动:
build.gradle
buildscript {
repositories {
google()
jcenter()
}
dependencies {
classpath 'com.android.tools.build:gradle:3.0.1'
classpath 'com.google.gms:google-services:3.2.1'
}
}
allprojects {
repositories {
google()
jcenter()
maven {
url "https://maven.google.com" // Google's Maven repository
}
}
}
rootProject.buildDir = '../build'
subprojects {
project.buildDir = "${rootProject.buildDir}/${project.name}"
}
subprojects {
project.evaluationDependsOn(':app')
}
task clean(type: Delete) {
delete rootProject.buildDir
}
app/build.gradle
def localProperties = new Properties()
def localPropertiesFile = rootProject.file('local.properties')
if (localPropertiesFile.exists()) {
localPropertiesFile.withReader('UTF-8') { reader ->
localProperties.load(reader)
}
}
def flutterRoot = localProperties.getProperty('flutter.sdk')
if (flutterRoot == null) {
throw new GradleException("Flutter SDK not found. Define location with flutter.sdk in the local.properties file.")
}
apply plugin: 'com.android.application'
apply from: "$flutterRoot/packages/flutter_tools/gradle/flutter.gradle"
android {
compileSdkVersion 27
lintOptions {
disable 'InvalidPackage'
}
defaultConfig {
// TODO: Specify your own unique Application ID (https://developer.android.com/studio/build/application-id.html).
applicationId "my.app.id"
multiDexEnabled true
minSdkVersion 16
targetSdkVersion 27
versionCode 1
versionName "1.0"
testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
}
buildTypes {
release {
// TODO: Add your own signing config for the release build.
// Signing with the debug keys for now, so `flutter run --release` works.
signingConfig signingConfigs.debug
}
}
}
flutter {
source '../..'
}
dependencies {
testImplementation 'junit:junit:4.12'
androidTestImplementation 'com.android.support.test:runner:1.0.1'
androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.1'
}
apply plugin: 'com.google.gms.google-services'
正如您可能猜到的那样，我已经尝试启用 multiDexEnabled 并升级 gradle 作为 GitHub 上建议的问题之一，但无济于事。
flutter --doctor
[√] Flutter (Channel master, v0.2.10-pre.39, on Microsoft Windows [Version 10.0.16299.371], locale en-US)
• Flutter version 0.2.10-pre.39 at E:\VSProjects\Flutter\flutter
• Framework revision d121cbc80d (3 days ago), 2018-04-08 09:46:11 -0700
• Engine revision d2b69fec75
• Dart version 2.0.0-dev.46.0.flutter-09e1766e6c
[!] Android toolchain - develop for Android devices (Android SDK 26.0.3)
• Android SDK at D:\AndroidSDK
• Android NDK location not configured (optional; useful for native profiling support)
• Platform android-27, build-tools 26.0.3
• ANDROID_HOME = D:\AndroidSDK
• Java binary at: C:\Program Files\Android\Android Studio\jre\bin\java
• Java version OpenJDK Runtime Environment (build 1.8.0_152-release-915-b01)
X Android license status unknown.
[√] Android Studio (version 3.0)
• Android Studio at C:\Program Files\Android\Android Studio
X Flutter plugin not installed; this adds Flutter specific functionality.
X Dart plugin not installed; this adds Dart specific functionality.
• Java version OpenJDK Runtime Environment (build 1.8.0_152-release-915-b01)
[√] VS Code, 64-bit edition (version 1.22.1)
• VS Code at C:\Program Files\Microsoft VS Code
• Dart Code extension version 2.11.2
[√] Connected devices (1 available)
• Android SDK built for x86 64 • emulator-5554 • android-x64 • Android 7.1.1 (API 25) (emulator)
pubspec.yaml
dependencies:
flutter:
sdk: flutter
google_sign_in: "^3.0.0"
附言
我在不引用 google-services 插件的情况下构建或运行 flutter 应用程序没有问题。
最佳答案
好的，经过几天的实验，我终于弄明白了。正如@cricket_007 和@rmtmckenzie 在对问题的评论中提到的，我没有将任何 Google/Firebase 服务添加到 pubspec.yaml 文件中。
我为初学者添加了 firebase_analytics，但没有帮助。通过反复试验，我发现我必须将 com.google.gms:google-services 的版本也降低到 3.1.0。现在我可以编译并打开我的应用程序。
关于java - 转换异常 : Multiple dex files define Lcom/google/android/gms/internal/zzcaw;，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/49785150/