Step 4. Add custom event

Here is my code example.

public class EventSkillAction extends AbstractEvent<SkillActionEvent> {
    @DataField(aliases = "d")
    public Direction direction; //You can handle enum constant too.
    @DataField(aliases = "w")
    public WeaponKey weaponKey;

    public EventSkillAction(QuestAdder adder, AbstractAction action) { //You must set constructor to this format: QuestAdder, T
        super(adder, action, SkillActionEvent.class);
    }

    @Override
    public void invoke(SkillActionEvent skillActionEvent) {
        if (direction != null && direction != skillActionEvent.getDirection()) return;
        if (weaponKey != null && weaponKey != skillActionEvent.getWeaponKey()) return;
        apply(skillActionEvent.getPlayer()); //Call this method to run action.
    }
}

QuestAdderAPI.getInstance().apiManager.addEvent("skillaction", EventSkillAction::class.java)

It actually works like this.

  variable:
    1:
      event: skillaction{w=LEFT}
      name: action_1
      lore: "play left attack 20 times."
      max: 20