Error:(27, 13) Failed to resolve: com.android.support.constraint:constraint-layout:1.0.2
<a href="install.m2.artifact">Install artifact and sync project</a><br><a href="openFile:E:/androidstudio/androidstudio_demo/location/SimpleLocation/app/build.gradle">Show in File</a><br><a href="open.dependency.in.project.structure">Show in Project Structure dialog</a>
解决办法:
android studio-->File-->settings-->Appearance&Behavior-->System Settings-->Android SDK-->SDK Tools-->Support Repository
如图下图：