Failed to resolve: com.android.support.constraint:constraint-layout:1.0.0-alpha9
来源： Failed to resolve: com.android.support.constraint:constraint-layout:1.0.0-alpha9 <a - CSDN博客 把一个工程导入as 的时候报错，Failed to resolve: com.android.support.constraint:constraint-layout:1.0.0-alpha9， 很明