打包aar的库中引用了databinding的依赖，然后在主工程引入aar时，build release包会报错，debug时正常。
Task :app:mergeDexRelease
AGPBI: {"kind":"error","text":"Type androidx.databinding.DataBindingComponent is defined multiple times: D:\\as\\work\\***\\build\\app\\intermediates\\project_dex_archive\\release\\dexBuilderRelease\\out\\androidx\\databinding\\DataBindingComponent.dex, D:\\as\\work\\***\\build\\app\\intermediates\\external_libs_dex\\release\\mergeExtDexRelease\\classes.dex","sources":[{"file":"D:\\as\\work\\***\\build\\app\\intermediates\\project_dex_archive\\release\\dexBuilderRelease\\out\\androidx\\databinding\\DataBindingComponent.dex"}],"tool":"D8"}
com.android.builder.dexing.DexArchiveMergerException: Error while merging dex archives:
Learn how to resolve the issue at https://developer.android.com/studio/build/dependencies#duplicate_classes.
Type androidx.databinding.DataBindingComponent is defined multiple times: D:\as\work\***\build\app\intermediates\project_dex_archive\release\dexBuilderRelease\out\androidx\databinding\DataBindingComponent.dex, D:\as\work\***\build\app\intermediates\external_libs_dex\release\mergeExtDexRelease\classes.dex
at com.android.builder.dexing.D8DexArchiveMerger.getMergingExceptionToRethrow(D8DexArchiveMerger.java:230)
at com.android.builder.dexing.D8DexArchiveMerger.mergeDexArchives(D8DexArchiveMerger.java:218)
at com.android.build.gradle.internal.tasks.DexMergingWorkAction.merge(DexMergingTask.kt:935)
at com.android.build.gradle.internal.tasks.DexMergingWorkAction.run(DexMergingTask.kt:884)
at com.android.build.gradle.internal.profile.ProfileAwareWorkAction.execute(ProfileAwareWorkAction.kt:74)
at org.gradle.workers.internal.DefaultWorkerServer.execute(DefaultWorkerServer.java:63)
at org.gradle.workers.internal.NoIsolationWorkerFactory$1$1.create(NoIsolationWorkerFactory.java:66)
at org.gradle.workers.internal.NoIsolationWorkerFactory$1$1.create(NoIsolationWorkerFactory.java:62)
at org.gradle.internal.classloader.ClassLoaderUtils.executeInClassloader(ClassLoaderUtils.java:100)
at org.gradle.workers.internal.NoIsolationWorkerFactory$1.lambda$execute$0(NoIsolationWorkerFactory.java:62)
at org.gradle.workers.internal.AbstractWorker$1.call(AbstractWorker.java:44)
at org.gradle.workers.internal.AbstractWorker$1.call(AbstractWorker.java:41)
at org.gradle.internal.operations.DefaultBuildOperationRunner$CallableBuildOperationWorker.execute(DefaultBuildOperationRunner.java:210)
at org.gradle.internal.operations.DefaultBuildOperationRunner$CallableBuildOperationWorker.execute(DefaultBuildOperationRunner.java:205)
at org.gradle.internal.operations.DefaultBuildOperationRunner$2.execute(DefaultBuildOperationRunner.java:67)
at org.gradle.internal.operations.DefaultBuildOperationRunner$2.execute(DefaultBuildOperationRunner.java:60)
at org.gradle.internal.operations.DefaultBuildOperationRunner.execute(DefaultBuildOperationRunner.java:167)
at org.gradle.internal.operations.DefaultBuildOperationRunner.execute(DefaultBuildOperationRunner.java:60)
at org.gradle.internal.operations.DefaultBuildOperationRunner.call(DefaultBuildOperationRunner.java:54)
at org.gradle.workers.internal.AbstractWorker.executeWrappedInBuildOperation(AbstractWorker.java:41)
at org.gradle.workers.internal.NoIsolationWorkerFactory$1.execute(NoIsolationWorkerFactory.java:59)
at org.gradle.workers.internal.DefaultWorkerExecutor.lambda$submitWork$0(DefaultWorkerExecutor.java:174)
at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
at org.gradle.internal.work.DefaultConditionalExecutionQueue$ExecutionRunner.runExecution(DefaultConditionalExecutionQueue.java:194)
at org.gradle.internal.work.DefaultConditionalExecutionQueue$ExecutionRunner.access$700(DefaultConditionalExecutionQueue.java:127)
at org.gradle.internal.work.DefaultConditionalExecutionQueue$ExecutionRunner$1.run(DefaultConditionalExecutionQueue.java:169)
at org.gradle.internal.Factories$1.create(Factories.java:31)
at org.gradle.internal.work.DefaultWorkerLeaseService.withLocks(DefaultWorkerLeaseService.java:263)
at org.gradle.internal.work.DefaultWorkerLeaseService.runAsWorkerThread(DefaultWorkerLeaseService.java:127)
at org.gradle.internal.work.DefaultWorkerLeaseService.runAsWorkerThread(DefaultWorkerLeaseService.java:132)
at org.gradle.internal.work.DefaultConditionalExecutionQueue$ExecutionRunner.runBatch(DefaultConditionalExecutionQueue.java:164)
at org.gradle.internal.work.DefaultConditionalExecutionQueue$ExecutionRunner.run(DefaultConditionalExecutionQueue.java:133)
at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:539)
at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
at org.gradle.internal.concurrent.ExecutorPolicy$CatchAndRecordFailures.onExecute(ExecutorPolicy.java:64)
at org.gradle.internal.concurrent.AbstractManagedExecutor$1.run(AbstractManagedExecutor.java:48)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1136)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635)
at java.base/java.lang.Thread.run(Thread.java:840)
Caused by: com.android.tools.r8.CompilationFailedException: Compilation failed to complete, origin: D:\as\work\***\build\app\intermediates\project_dex_archive\release\dexBuilderRelease\out\androidx\databinding\DataBindingComponent.dex
at Version.fakeStackEntry(Version_8.13.6.java:0)
at com.android.tools.r8.q0.a(R8_8.13.6_1c658b3b683138d620220f6965281391a8f410eddb02f3ff35a06caf88d6c59d:1)
at com.android.tools.r8.internal.is0.a(R8_8.13.6_1c658b3b683138d620220f6965281391a8f410eddb02f3ff35a06caf88d6c59d:81)
at com.android.tools.r8.internal.is0.a(R8_8.13.6_1c658b3b683138d620220f6965281391a8f410eddb02f3ff35a06caf88d6c59d:32)
at com.android.tools.r8.internal.is0.a(R8_8.13.6_1c658b3b683138d620220f6965281391a8f410eddb02f3ff35a06caf88d6c59d:31)
at com.android.tools.r8.internal.is0.b(R8_8.13.6_1c658b3b683138d620220f6965281391a8f410eddb02f3ff35a06caf88d6c59d:2)
at com.android.tools.r8.D8.run(R8_8.13.6_1c658b3b683138d620220f6965281391a8f410eddb02f3ff35a06caf88d6c59d:11)
at com.android.builder.dexing.D8DexArchiveMerger.mergeDexArchives(D8DexArchiveMerger.java:216)
... 37 more
Caused by: com.android.tools.r8.CompilationFailedException: Compilation failed to complete, origin: D:\as\work\***\build\app\intermediates\project_dex_archive\release\dexBuilderRelease\out\androidx\databinding\DataBindingComponent.dex错误原因，
-
库工程引入了databinding的库，导致重复
-
库工程依赖的其他库，没有使用databinding的库，也需要开启databinding，然后再打包。
3.解决方法如下，在依赖的库中，全部指定依赖版本，并用compileOnly 引用。然后打包成aar，放到主工程即可compileOnly 'androidx.databinding:databinding-runtime:8.13.0' compileOnly 'androidx.databinding:databinding-adapters:8.13.0' compileOnly 'androidx.databinding:databinding-ktx:8.13.0' compileOnly 'androidx.databinding:databinding-common:8.13.0'