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Give a screen or flow its own state machine

How to drive a UI screen or a local flow (idle → loading → active → done) through named states with enter/exit callbacks, using StateManager instead of a pile of booleans.

Steps​

  1. Spawn one for the screen or flow that needs it. StateManager ships as one of TsVRC's own default factory entries, so there's nothing to register on the Configure window first. Give each screen its own instance rather than sharing one across unrelated screens:

    public class SettingsScreen : TsBehaviour
    {
        private const int StateIdle = 0;
        private const int StateLoading = 1;
        private const int StateReady = 2;

        [SerializeField] private GameObject _panel;
        [SerializeField] private GameObject _spinner;
        private StateManager _state;

        protected override void TsStart()
        {
            _state = _ts.CreateStateManager(transform);
            _state.RegisterState(StateIdle, this, enterMethod: nameof(OnEnterIdle));
            _state.RegisterState(StateLoading, this, enterMethod: nameof(OnEnterLoading), exitMethod: nameof(OnExitLoading));
            _state.RegisterState(StateReady, this, enterMethod: nameof(OnEnterReady));
            _state.SetState(StateIdle);
        }

        public void OnEnterIdle() => _panel.SetActive(false);
        public void OnEnterLoading() => _spinner.SetActive(true);
        public void OnExitLoading() => _spinner.SetActive(false);
        public void OnEnterReady() => _panel.SetActive(true);
    }

  2. Trigger transitions from wherever your own logic decides, not from inside another state's own enter/exit method chain:

    public void StartLoadingSettings() => _state.SetState(StateLoading);

  3. If something outside this screen needs to react to every transition generically (analytics, a shared loading spinner), subscribe to the state manager's own event instead of duplicating calls at every SetState call site:

    _state.TsSubscribe(this, "OnStateChanged", nameof(_OnAnyStateChanged));

Why one instance per screen​

A StateManager instance only knows the states you've registered on it. Sharing one across unrelated screens means their state numbers collide (StateLoading = 1 on one screen is a different concept than StateLoading = 1 on another) unless you're careful to give every screen's states globally unique numbers. A fresh instance per screen avoids that entirely, and costs nothing extra: _ts.CreateStateManager is a cheap, local, non-networked spawn.

Why this shape​

See StateManager's reference page for what happens if an enter/exit method or a subscriber throws mid-transition, how a reentrant SetState call from inside an enter/exit method is queued rather than interleaved, and why StateManager needs no TsConstruct at all if you want to skip the factory and use one completely manually.