Problem :
Error:Could not find com.android.support.constraint:constraint-layout:1.0.0-alpha2.
Required by:
myapp:app:unspecified
In my case, I had a multi-module project called "app" and "sdk". The "sdk" module is the one where I had added the constraint layout library. I got the error when I tried to incorporate "sdk" into a new multi-module project called "app2". The solution was to ensure I had added the Google Maven Repository to the project-level build.gradle file for "app2". The Google Maven Repository can be added by putting "google()" under allprojects.repositories
in the project-level build.gradle file:
allprojects {
repositories {
jcenter()
google()
}
}