问题
when build , show this error :
Unable to resolve dependency for ':app@debug/compileClasspath': Could not resolve com.android.support:appcompat-v7:27.1.1.
回答1:
Just add google() under repositories as highlighted in attached picture to your project gradle, as google has move its repositories to maven you have to add this way, hope this helps you!!! or read this official doc Support Library Setup
Another nice asnwer by Gabriele Mariotti Using google() as a repository doesn't work
来源：https://stackoverflow.com/questions/49854833/unable-to-resolve-dependency