Not able to copy configurations dependencies after upgrading Gradle plugin for Android Studio to 3.0.1 and Gradle to 4.1

Question

I used to copy 'compile' dependencies to a specific folder using this simple gradle task :

task copyLibs(type: Copy) {
    from configurations.compile
    into "$project.rootDir/reports/libs/"
}

But it stopped working just after upgrading my Android project using gradle plugin 3.0.1 for Android Studio and Gradle tool to 4.1. As the dependency configuration 'compile' is now deprecated by https://developer.android.com/studio/build/gradle-plugin-3-0-0-migration.html#new_configurations I changed it to 'implementation'. However, I am not able to use my copyLibs task as resolving configuration 'implementation' directly is not allowed as per Gradle build error output :

$ ./gradlew.bat clean build

FAILURE: Build failed with an exception.

* What went wrong:
Could not determine the dependencies of task ':app:copyLibs'.
> Resolving configuration 'implementation' directly is not allowed

* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output.

* Get more help at https://help.gradle.org

BUILD FAILED in 1s

See following my current build.gradle file for app module : apply plugin: 'com.android.application'

android {
    compileSdkVersion 26
    defaultConfig {
        applicationId "newgradle.com.testingnewgradle"
        minSdkVersion 21
        targetSdkVersion 26
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    implementation 'com.android.support:appcompat-v7:26.1.0'
    implementation 'com.android.support:support-v4:26.1.0'
    implementation 'com.android.support:design:26.1.0'
    implementation 'com.android.support.constraint:constraint-layout:1.0.2'
    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'
}

task copyLibs(type: Copy) {
    from configurations.implementation
    into "$project.rootDir/reports/libs/"
}
build.dependsOn copyLibs

If I use 'compile' it works but I would like to be compliant with the latest recommendation on this plugin the usage.

I need help to upgrade my copyLibs task in order to work as before upgrading my enviromment. I was using gradle plugin 2.2.3 for Android Studio and Gradle tool 2.14.1.

Answer 1

instead of using configurations.implementation, the best option is to use: configurations.runtimeClasspath

you can also think about: compileClasspath default