Execution failed for task ':app:checkDebugDuplicateClasses'

* What went wrong:
Execution failed for task ':app:checkDebugDuplicateClasses'.
> A failure occurred while executing com.android.build.gradle.internal.tasks.CheckDuplicatesRunnable

在 build.gradle(:daocore) 中将 compile 'com.android.support:appcompat-v7:26.+’ 替换为 implementation 'androidx.appcompat:appcompat:1.2.0’ 即可