Utils/SingletonComponent.cs
Generic singleton Component base class for s&box game code. It stores a static Instance of the derived type, sets it on awake if the component is active, clears it on destroy, and participates in hotload management by saving/restoring whether this instance was active across hotloads.
public abstract class SingletonComponent<T> : Component, IHotloadManaged
where T : SingletonComponent<T>
{
public static T Instance { get; private set; }
protected override void OnAwake()
{
if (Active)
{
Instance = (T)this;
}
}
void IHotloadManaged.Destroyed(Dictionary<string, object> state)
{
state["IsActive"] = Instance == this;
}
void IHotloadManaged.Created(IReadOnlyDictionary<string, object> state)
{
if (state.GetValueOrDefault("IsActive") is true)
{
Instance = (T)this;
}
}
protected override void OnDestroy()
{
if (Instance == this)
{
Instance = null;
}
}
}