java - NoClassDefFoundError: ... R$styleable when using Robolectric with Android Library (AAR) -

we developing library provides activity, , able perform functional testing on activity.

my build.gradle includes:

dependencies {     compile filetree(dir: 'libs', include: ['*.jar'])     compile 'com.android.support:appcompat-v7:22.1.1'      testcompile 'org.mockito:mockito-core:1.+'     testcompile 'junit:junit:4.12'     testcompile('org.robolectric:robolectric:3.0-rc2') {         exclude group: 'commons-logging', module: 'commons-logging'         exclude group: 'org.apache.httpcomponents', module: 'httpclient'     }     testcompile('org.robolectric:shadows-httpclient:3.0-rc2') {         exclude group: 'commons-logging', module: 'commons-logging'         exclude group: 'org.apache.httpcomponents', module: 'httpclient'     }     testcompile('org.robolectric:shadows-support-v4:3.0-rc2') {         exclude group: 'commons-logging', module: 'commons-logging'         exclude group: 'org.apache.httpcomponents', module: 'httpclient'     } } 

and libraryactivitytest includes:

@runwith(robolectricgradletestrunner.class) public class libraryactivitytest {      @test     public void testoncreate() throws exception {         libraryactivity libraryactivity = robolectric.buildactivity(libraryactivity.class).create().get();       } } 

myrobolectricgradletestrunner overrides getappmanifest restore ability specify test-specific androidmanifest.xml instead of using application version.

when attempt run testoncreate android studio or gradle command line, class def not found error android/support/v7/appcompat/r$styleable:

android/support/v7/appcompat/r$styleable java.lang.noclassdeffounderror: android/support/v7/appcompat/r$styleable     @ android.support.v7.app.appcompatdelegateimplbase.oncreate(appcompatdelegateimplbase.java:109)     @ android.support.v7.app.appcompatdelegateimplv7.oncreate(appcompatdelegateimplv7.java:146)     @ android.support.v7.app.appcompatactivity.oncreate(appcompatactivity.java:59)     @ com.moxiesoft.mylibrary.libraryactivity.oncreate(libraryactivity.java:13)     @ android.app.activity.performcreate(activity.java:5133)     @ org.robolectric.util.reflectionhelpers$3.run(reflectionhelpers.java:144)     @ org.robolectric.util.reflectionhelpers.traverseclasshierarchy(reflectionhelpers.java:241)     @ org.robolectric.util.reflectionhelpers.callinstancemethod(reflectionhelpers.java:138)     @ org.robolectric.util.activitycontroller$1.run(activitycontroller.java:122)     @ org.robolectric.shadows.shadowlooper.runpaused(shadowlooper.java:309)     @ org.robolectric.shadows.coreshadowsadapter$2.runpaused(coreshadowsadapter.java:47)     @ org.robolectric.util.activitycontroller.create(activitycontroller.java:118)     @ org.robolectric.util.activitycontroller.create(activitycontroller.java:129)     @ com.moxiesoft.mylibrary.libraryactivitytest.testoncreate(libraryactivitytest.java:20)     @ org.junit.runners.model.frameworkmethod$1.runreflectivecall(frameworkmethod.java:50)     @ org.junit.internal.runners.model.reflectivecallable.run(reflectivecallable.java:12)     @ org.junit.runners.model.frameworkmethod.invokeexplosively(frameworkmethod.java:47)     @ org.junit.internal.runners.statements.invokemethod.evaluate(invokemethod.java:17)     @ org.robolectric.robolectrictestrunner$2.evaluate(robolectrictestrunner.java:235)     @ org.junit.runners.parentrunner.runleaf(parentrunner.java:325)     @ org.junit.runners.blockjunit4classrunner.runchild(blockjunit4classrunner.java:78)     @ org.junit.runners.blockjunit4classrunner.runchild(blockjunit4classrunner.java:57)     @ org.junit.runners.parentrunner$3.run(parentrunner.java:290)     @ org.junit.runners.parentrunner$1.schedule(parentrunner.java:71)     @ org.junit.runners.parentrunner.runchildren(parentrunner.java:288)     @ org.junit.runners.parentrunner.access$000(parentrunner.java:58)     @ org.junit.runners.parentrunner$2.evaluate(parentrunner.java:268)     @ org.robolectric.robolectrictestrunner$1.evaluate(robolectrictestrunner.java:168)     @ org.junit.runners.parentrunner.run(parentrunner.java:363)     @ org.gradle.api.internal.tasks.testing.junit.junittestclassexecuter.runtestclass(junittestclassexecuter.java:86)     @ org.gradle.api.internal.tasks.testing.junit.junittestclassexecuter.execute(junittestclassexecuter.java:49)     @ org.gradle.api.internal.tasks.testing.junit.junittestclassprocessor.processtestclass(junittestclassprocessor.java:69)     @ org.gradle.api.internal.tasks.testing.suitetestclassprocessor.processtestclass(suitetestclassprocessor.java:48)     @ org.gradle.messaging.dispatch.reflectiondispatch.dispatch(reflectiondispatch.java:35)     @ org.gradle.messaging.dispatch.reflectiondispatch.dispatch(reflectiondispatch.java:24)     @ org.gradle.messaging.dispatch.contextclassloaderdispatch.dispatch(contextclassloaderdispatch.java:32)     @ org.gradle.messaging.dispatch.proxydispatchadapter$dispatchinginvocationhandler.invoke(proxydispatchadapter.java:93)     @ com.sun.proxy.$proxy2.processtestclass(unknown source)     @ org.gradle.api.internal.tasks.testing.worker.testworker.processtestclass(testworker.java:105)     @ org.gradle.messaging.dispatch.reflectiondispatch.dispatch(reflectiondispatch.java:35)     @ org.gradle.messaging.dispatch.reflectiondispatch.dispatch(reflectiondispatch.java:24)     @ org.gradle.messaging.remote.internal.hub.messagehub$handler.run(messagehub.java:360)     @ org.gradle.internal.concurrent.defaultexecutorfactory$stoppableexecutorimpl$1.run(defaultexecutorfactory.java:64)     @ java.util.concurrent.threadpoolexecutor.runworker(threadpoolexecutor.java:1142)     @ java.util.concurrent.threadpoolexecutor$worker.run(threadpoolexecutor.java:617)     @ java.lang.thread.run(thread.java:745) 

it's worth noting installation , configuration seems reasonable, tests don't involve activitycontroller.create seem work fine.

how can resolve error?

so root of problem seems how gradle (or not) handle creating android/support/v7/appcompat/r.java com.android.library modules.

with clues here able things working both command line , android putting chunk in build.gradle

def package_namespace = "com.moxiesoft.netagent.androidchatcustomerclient" def package_namespace_path = package_namespace.replaceall("\\.", "/")  afterevaluate { project ->     android.libraryvariants.each { variant ->         // workaround missing r class aar dependencies         def copytaskname = "copy${variant.name.capitalize()}appcompat"         task(copytaskname, type:copy) {             dependson "process${variant.name.capitalize()}resources"             "build/generated/source/r/${variant.name}/$package_namespace_path" //            "build/generated/source/r/${variant.name}/android/support/v7/appcompat"             "src/test/java/android/support/v7/appcompat"             include 'r.java'             filter { line -> line.contains("package ${package_namespace};") ? 'package android.support.v7.appcompat;' : line }             outputs.uptodatewhen { false }         }         tasks.getbyname("compile${variant.name.capitalize()}unittestjava") dependson copytaskname     } } 

basically it's copying generated application r.java file tests build folder gets picked test compilation phase. tried putting copy generated sources folder, test compile phase doesn't seem pick there.