SBT compilation for play framework 2.x disabled by default
Solution 1:
Preferences > Languages & Frameworks > Play2
Under 'Compiler' enable 'Use Play 2 compiler for this project'
Solution 2:
I Stumbled upon this problem myself when configuring play framework for IntelliJ IDEA IDE (version: 2017.3). I overcame this problem by following the steps below.
Navigate to:
File --> Settings --> Languages and Frameworks --> Play2 --> Compiler tab
and inside the compiler tab:
put a tick to the Use Play2 compiler for this project
Hope this helped.