Android构建时报错：Execution failed fo

今天在引入 butterknife (compile 'com.jakewharton:butterknife:7.0.1') 后构建项目时遇到一个错误：

Error:Execution failed for task ':app:javaPreCompileDebug'.

> Annotation processors must be explicitly declared now.  The following dependencies on the compile classpath are found to contain annotation processor.  Please add them to the annotationProcessor configuration.

    - butterknife-7.0.1.jar (com.jakewharton:butterknife:7.0.1)

  Alternatively, set android.defaultConfig.javaCompileOptions.annotationProcessorOptions.includeCompileClasspath = true to continue with previous behavior.  Note that this option is deprecated and will be removed in the future.

  See https://developer.android.com/r/tools/annotation-processor-error-message.html for more details.

百度后找到的解决方案是

在app的build中

android {

    ...

    defaultConfig {

        ...

        //添加如下配置就OK了

        javaCompileOptions { annotationProcessorOptions { includeCompileClasspath = true } }

    }

    ...

}