Schedulers

There are two types of schedulers in ducklib, TriggerSchedulers and CommandSchedulers.

TriggerScheduler

The TriggerScheduler handles running actions on a trigger's rising edge and falling edge. This can be used to bind actions to gamepad inputs, state changes, and similar things.

For example, using the gamepad extension API:

driver[ButtonInput.A]
    .onceOnTrue({ servo.position = 0.5 }.instant(servo))
    .onceOnFalse({ servo.position = 0.0 }.instant(servo))

Here, a command is created inline and bound to a trigger.

CommandScheduler

The CommandScheduler handles running commands, and gracefully handling requirement conflicts as they arise.

DuckyScheduler

DuckyScheduler is the default implementation of both of these in ducklib. It fully implements the priority and requirement systems in ducklib.

You can use the companion instance:

// the rest of the imports are omitted
import com.escapevelocity.ducklib.core.command.scheduler.DuckyScheduler
import com.escapevelocity.ducklib.core.command.scheduler.DuckyScheduler.Companion.onceOnFalse
import com.escapevelocity.ducklib.core.command.scheduler.DuckyScheduler.Companion.onceOnTrue
import com.escapevelocity.ducklib.core.command.scheduler.DuckyScheduler.Companion.schedule

class MyOpMode : OpMode {
    fun initialize() {
        val cmd = NoOpCommand()
        // uses the DuckyScheduler companion instance
        cmd.schedule()
    }
}

or make your own:

import com.escapevelocity.ducklib.core.command.scheduler.DuckyScheduler
import com.escapevelocity.ducklib.core.command.scheduler.DuckyScheduler.Companion.onceOnFalse
import com.escapevelocity.ducklib.core.command.scheduler.DuckyScheduler.Companion.onceOnTrue
import com.escapevelocity.ducklib.core.command.scheduler.DuckyScheduler.Companion.schedule

class MyOpMode : OpMode {
    val cs = DuckyScheduler()

    fun initialize() {
        val cmd = NoOpCommand()
        // uses the custom instance
        with (cs) {
            cmd.schedule()
        }
    }
}

This is commonly done for thread-safety, since DuckyScheduler isn't thread-safe by itself.