安卓工作室: 级别同步失败: 无法启动“ ...”。从服务器接收到状态代码502: 坏网关

After updating the Android Studio to 3.1.0 ,

I just had the same problem, i resolved it using

 maven {   url "https://maven.google.com"  }

to the TopMost buildScript like this in project-level gradle :-

 buildscript {
repositories {
.....
...
maven {   url "https://maven.google.com"   }

For reference take a sample of the project-level gradle:-

buildscript {


repositories {
google()
jcenter()
maven { url 'https://maven.fabric.io/public' }
maven { url 'https://jitpack.io' }
mavenCentral()
maven { url 'https://maven.fabric.io/public' }
maven {  url "https://maven.google.com"  }
}
dependencies {
classpath 'com.android.tools.build:gradle:3.1.0'
classpath 'io.fabric.tools:gradle:1.24.4'
}
}


allprojects {
repositories {
google()
jcenter()
}
}


task clean(type: Delete) {
delete rootProject.buildDir
}

Note :- One more thing:-

In gradle-wrapper.properties use this :-

  distributionUrl=https\://services.gradle.org/distributions/gradle-4.4-all.zip

Instead of 4.1-all.zip .

Edit :- If you want to resolve the issue fast , you can also try adding these - according to Omar's answer :-

 maven { url "http://dl.bintray.com/riteshakya037/maven" }

along with

  maven { url "https://maven.google.com" }

I've just clicked Disable Gradle 'offline mode' and sync project and Android Studio downloaded all the needed files.

jcenter is having issues at the moment, please check http://status.bintray.com/

EDIT: it looks like the link above was sunset, new link at: https://status.gradle.com/

Thanks to everyone for the quick answers!

It seems like temporary network issues on the "jcenter.bintray.com" website. I just clicked "Try Again" many times and in the end everything was updated.

Also, if you open the links in the browser - from time to time you will receive a "Service Error" message. So the problem is not on your side.

Ok, I slove it by:

In your build.gradle project level, add this:

buildscript {
...
repositories {
google()
jcenter()
maven { url 'https://maven.fabric.io/public' }
maven { url 'https://jitpack.io' }
mavenCentral()
maven { url "https://maven.google.com" }
}
dependencies {
classpath 'com.android.tools.build:gradle:3.1.0' // Updated from 3.0 to 3.1.0


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

Note that I've updated gradle from 3.0 to 3.1.0

Next: add the same previous links to allprojects's repository body:

allprojects {
repositories {
google()
jcenter()
mavenCentral()
maven { url 'https://jitpack.io' }
maven { url "https://maven.google.com" }
maven { url 'https://maven.fabric.io/public' }
}

}

One more thing:

In gradle-wrapper.properties use this :

distributionUrl=https://services.gradle.org/distributions/gradle-4.4-all.zip

After that, just sync again, and it will work.

For me after applying Santanu Sur's answer The error hapenned again but with another library I have check project's gradle and I found this line maven { url "http://dl.bintray.com/riteshakya037/maven" } in

allprojects {
repositories {
maven { url "http://dl.bintray.com/riteshakya037/maven" }
maven { url "https://jitpack.io" }
jcenter()
google()
}
}

I deleted it, and everything is good now

It's a server response error. Keep trying by pressing "Try Again" after some time. It will be ok automatically.

Tip:
When you get your project to build correctly the once enable offline-mode so AS don't have to connect to jcenter every gradle refresh.

Uninstalling and Download & install from Developer site solved the issue for me.