Java 我正在尝试在我的应用程序中添加google signin，但此依赖项不起作用 app/build.gradle 无法解析“”的依赖项：app@debug/compileClasspath'：无法解析com.google.android.gms:play services auth:15.0.1。 无法解析“”的依赖项：app@debugAndroidTest/compileClasspath'：无法解析com.google.android.gms:play services auth:15.0.1。 无法解析“”的依赖项：app@debugUnitTest/compileClasspath'：无法解析com.google.android.gms:play services auth:15.0.1。 无法解析“”的依赖项：app@release/compileClasspath'：无法解析com.google.android.gms:play services auth:15.0.1。 无法解析“”的依赖项：app@releaseUnitTest/compileClasspath'：无法解析com.google.android.gms:play services auth:15.0.1。

用最新版本更新您的project gradle文件

app/build.gradle    
Unable to resolve dependency for ':app@debug/compileClasspath': Could not resolve com.google.android.gms:play-services-auth:15.0.1.
<a href="openFile:D:/DeVEloPER/Android/InternshipProjects/Watchman/app/build.gradle">Open File</a><br><a href="Unable to resolve dependency for &#39;:app@debug/compileClasspath&#39;: Could not resolve com.google.android.gms:play-services-auth:15.0.1.">Show Details</a>    
Unable to resolve dependency for ':app@debugAndroidTest/compileClasspath': Could not resolve com.google.android.gms:play-services-auth:15.0.1.
<a href="openFile:D:/DeVEloPER/Android/InternshipProjects/Watchman/app/build.gradle">Open File</a><br><a href="Unable to resolve dependency for &#39;:app@debugAndroidTest/compileClasspath&#39;: Could not resolve com.google.android.gms:play-services-auth:15.0.1.">Show Details</a> 
Unable to resolve dependency for ':app@debugUnitTest/compileClasspath': Could not resolve com.google.android.gms:play-services-auth:15.0.1.
<a href="openFile:D:/DeVEloPER/Android/InternshipProjects/Watchman/app/build.gradle">Open File</a><br><a href="Unable to resolve dependency for &#39;:app@debugUnitTest/compileClasspath&#39;: Could not resolve com.google.android.gms:play-services-auth:15.0.1.">Show Details</a>    
Unable to resolve dependency for ':app@release/compileClasspath': Could not resolve com.google.android.gms:play-services-auth:15.0.1.
<a href="openFile:D:/DeVEloPER/Android/InternshipProjects/Watchman/app/build.gradle">Open File</a><br><a href="Unable to resolve dependency for &#39;:app@release/compileClasspath&#39;: Could not resolve com.google.android.gms:play-services-auth:15.0.1.">Show Details</a>  
Unable to resolve dependency for ':app@releaseUnitTest/compileClasspath': Could not resolve com.google.android.gms:play-services-auth:15.0.1.
<a href="openFile:D:/DeVEloPER/Android/InternshipProjects/Watchman/app/build.gradle">Open File</a><br><a href="Unable to resolve dependency for &#39;:app@releaseUnitTest/compileClasspath&#39;: Could not resolve com.google.android.gms:play-services-auth:15.0.1.">Show Details</a>  

还处

 classpath 'com.android.tools.build:gradle:3.1.0'
    classpath 'com.google.gms:google-services:3.0.0'

---

在应用程序gradle依赖项的底部。

您能否显示项目的顶级

build.gradle

和应用程序级别

build.gradle

文件？

apply plugin: 'com.google.gms.google-services'