Android studio 3.0: Unable to resolve dependency for :app@dexOptions/compileClasspath': Could not resolve project :animators

Question

With Android Studio 2.3(AS) the project works fine and i can able to run the App. After updating the AS to Android Studio 3.0. i too got the error as below for libraries and build types.

Unable to resolve dependency for ':app@dexOptions/compileClasspath': Could not resolve project : library_Name.

Unable to resolve dependency for ':app@release/compileClasspath': Could not resolve project : library_Name.

To Solve the issue, simply.

What ever the

buildTypes{
          debug{ ... }
          release{ ... }
    }

you have in your (app) build.gradle file, You have to include all the buildTypes{ } with same names as like

buildTypes{
      debug{ ... }
      release{ ... }
}

in to build.gradle files of All libraries/modules included in project.

clean and rebuild the project, the issue will be fixed.

Still issue not fixed, update the gradle-wrapper.properties to

distributionUrl=https\://services.gradle.org/distributions/gradle-4.1-all.zip

As stated in the official migration guide, this error is encountered when:

Your app includes a build type that a library dependency does not

android {
  buildTypes {
      release {
          ...
      }
      dexOptions {
          ...
        // release & debug is in project animators
        matchingFallbacks = ['release', 'debug']
      }
      debug {
          ...
      }
    }
}

Correct place to find the info is now this documentation

Make sure you're in your project

1. Open the Preferences, by clicking File > Settings (on Mac, Android Studio > Preferences).
2. In the left pane, click Build, Execution, Deployment >> Gradle.
3. Uncheck/disable the Offline work checkbox.
4. Click Apply or OK.

I spent a lot of time on this issue and none of above solutions work for me. The names and number of build types were also exactly equal in both app and library project.

The only mistake I was making was - In library project's build.gradle, I was using line

apply plugin: 'com.android.application'

While this line should be -

apply plugin: 'com.android.library'

After making this change, this error got resolved.