FTC Programming with ElectronVolts

Let's say you have a state machine drawing that looks like this:

 _______        ____________        ______
|       \      |            |      /      \
| START  \ ==> |  wait for  | ==> |  STOP  |
|        /     |  1 second  |     |        |
|_______/      |____________|      \______/

To create a state machine based on this diagram, first create an enum that implements [StateName](The State Interface.md) with your list of states:

enum S implements StateName {
    WAIT,
    STOP
};

Then create a StateMachineBuilder, giving it the state to start with:

StateMachineBuilder b = new StateMachineBuilder(S.WAIT);

Add all the states to the builder:

//add a wait state named WAIT for 1000 milliseconds, then go to the state named STOP
b.addWait(S.WAIT, S.STOP, 1000);

//add a stop state named STOP
b.addStop(S.STOP);

Build the state machine and save it to a variable.

StateMachine stateMachine = b.build();

Add the following to a loop method to run the state machine:

stateMachine.act();

//use this for the FTC app:
telemetry.addData("State", stateMachine.getCurrentStateName());

//use this for other usages:
System.out.println("State: " + stateMachine.getCurrentStateName());

On the telemetry of the FTC app, or the console in other applications, this will be displayed:

State: WAIT
State: WAIT
State: WAIT
State: WAIT
...
State: WAIT
State: WAIT
State: STOP
State: STOP
State: STOP
State: STOP
...

Congratulations! You made your first state machine!

The next step is to create Custom States.