Question Call mono method from system

I'm sure this is super simple but I can't get the right combination to call a monobehaviour method from a system.

Code (CSharp):

1. public class SomeMonoBehaviourUI : MonoBehaviour
2.     {
3.         public void DoSomething()
4.         {
5.             Debug.Log("DoSomething");
6.         }
7.     }
8.  
9.     public class Baker : Baker<SomeMonoBehaviourUI>
10.       {
11.           public override void Bake(SomeMonoBehaviourUI authoring)
12.           {
13.               var entity = GetEntity(TransformUsageFlags.None);
14.               // How do I add the SomeMonoBehaviourUI to the entity?
15.           }
16.       }
17.     public partial class SomeUISystem : SystemBase
18.     {
19.         protected override void OnUpdate()
20.         {
21.             Entities.ForEach((in SomeMonoBehaviourUI ui) =>
22.             {
23.                 ui.DoSomething();
24.             }).WithoutBurst().Run();
25.         }
26.     }

I have tried AddComponentObject(entity, ----) with a bunch of different items with no luck.

 

You can't directly attach a MonoBehaviour to an entity in a baker.

 

Ok so what’s the bridge between the system and mono behavior,,I feel like this is stupid simple but I haven’t been able to connect them

 

Hacks.

I'm being honest with you here. In my opinion, there's no clean way to do it. I've done it a couple of different ways, and I know others here have their favorite hacks. But really, they are all just hacks because there is no proper solution.

 

Interesting, they provide you a way to easily connect a mono to a system through the EntityManager but everybody (including Unity) says that you want the data to flow the other way but don't provide an easy way to do it.

 

This is just as hacky honestly.

 

Simplest (and most robust) solution is to avoid baking for this case.

If you want MonoBehaviour (or any UnityEngine.Object) attached to the entity - reverse control it.
Let MonoBehaviour author entity & keep it in the scene (not subscene).

For better non-baking authoring you could take a peek at EntitiesExt.