Gradle无法解析com.firebaseui:firebase-ui-auth:3.2.1问题求助

我最近碰到了Gradle同步失败的问题，报错提示无法解析com.firebaseui:firebase-ui-auth:3.2.1。我已经做了这些常规排查但问题还是没解决：

• 用了Firebase和Google Play Services的最新依赖（版本11.8.0）
• 在Firebase控制台里启用了对应的登录选项
• 已经把google-services.json正确放在了app目录下

我的Gradle配置文件 #

app/build.gradle

apply plugin: 'com.android.application'
android {
    compileSdkVersion 27
    buildToolsVersion '26.0.2'
    defaultConfig {
        applicationId 'com.google.firebase.example.fireeats'
        minSdkVersion 16
        targetSdkVersion 27
        versionCode 1
        versionName '1.0'
        vectorDrawables.useSupportLibrary true
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}
dependencies {
    // Firestore
    compile 'com.google.firebase:firebase-firestore:11.8.0'
    // Other Firebase/Play services deps
    compile 'com.google.firebase:firebase-auth:11.8.0'
    compile 'com.google.android.gms:play-services-auth:11.8.0'
    // FirebaseUI (for authentication)
    compile 'com.firebaseui:firebase-ui-auth:3.2.1'
    // ButterKnife (for sample code brevity)
    compile 'com.jakewharton:butterknife:8.7.0'
    annotationProcessor 'com.jakewharton:butterknife-compiler:8.7.0'
    // Support Libs
    compile 'com.android.support:appcompat-v7:27.0.1'
    compile 'com.android.support:animated-vector-drawable:27.0.1'
    compile 'com.android.support:cardview-v7:27.0.1'
    compile 'com.android.support:customtabs:27.0.1'
    compile 'com.android.support:design:27.0.1'
    compile 'com.android.support:recyclerview-v7:27.0.1'
    // Android architecture components
    compile 'android.arch.lifecycle:runtime:1.0.0-alpha9'
    compile 'android.arch.lifecycle:extensions:1.0.0-alpha9'
    annotationProcessor 'android.arch.lifecycle:compiler:1.0.0-alpha9'
    // Third-party libraries
    compile 'me.zhanghai.android.materialratingbar:library:1.0.2'
    compile 'com.github.bumptech.glide:glide:3.7.0'
}
apply plugin: 'com.google.gms.google-services'

project/build.gradle

// Top-level build file where you can add configuration options common to all sub-projects/modules.
buildscript {
    repositories {
        mavenCentral()
        jcenter()
        google()
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:2.3.0'
        classpath 'com.google.gms:google-services:3.1.0'
    }
}
allprojects {
    repositories {
        maven { url 'https://maven.google.com' }
        jcenter()
        google()
        mavenLocal()
    }
}
task clean(type: Delete) {
    delete rootProject.buildDir
}

解决方案 #

虽然FirebaseUI官方GitHub文档里标注3.2.1版本对应Firebase/Play Services 11.8.0，但这个版本组合在我的项目里无法正常解析依赖。我尝试把FirebaseUI版本从3.2.1降级到3.1.3后，Gradle同步就成功完成了。

内容的提问来源于stack exchange，提问作者Akash Raj