Android开发中遇到的坑

1. android studio升级3.0后新建项目报错：

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

> Conflict with dependency 'com.android.support:support-annotations' in project ':app'. Resolved versions for app (26.1.0) and test app (27.1.1) differ. See https://d.android.com/r/tools/test-apk-dependency-conflicts.html for details.

解决方法：

在build.gradle文件中添加：

android {
    configurations.all {
        resolutionStrategy.force 'com.android.support:support-annotations:27.1.1'
    }
}