报错Resolved versions for app (26.1.0) and test app (27.1.1) differ.”

问题：

Build failed：“Conflict with dependency 'com.android.support:support-annotations' in project ':mobile'. Resolved versions for app (26.1.0) and test app (27.1.1) differ.” 

mobile的build.gradle如下

解决办法：

1.

implementation 'com.android.support:appcompat-v7:26.1.0'修改为28.0.0,

compileSdkVersion和targetSdkVersion都修改为28

再删除implementation 'com.google.android.gms:play-services-wearable:+'

2.

如果需要保留implementation 'com.google.android.gms:play-services-wearable:+'

appcompat的版本不能修改为高版本，所需要为添加配置：

configurations.all {
    resolutionStrategy.force 'com.android.support:support-annotations:26.1.0'
}

再同步后rebuild