Accessing Joystick Axes in Command-Based Robot

[Sparkyshires]

Hello all,

This is my first time programming in the command-based template, and I've made it pretty far until I've hit a dead wall - I can't send joystick control to the motors. As the motors are controlled in the subsystem class, and the joysticks are instantiated in the OI class, how can they communicate to each other? I'm just trying to do a basic "if button is pressed, send stick1 y-axis to motor output" with a drive command, drivetrain class, and joystick variable.

Any help is appreciated, thank you very much!