Customizing registration in MonoBehaviours

This feature is specific for MonoBehaviours. For an example in pure C# see using eventbus outside of monobehaviours

See the below snippet for more info, pay attention in specific to the usage of IEventReceiver<T1, T2>.

public class OnHelloWorldEvent
{
    public string Message;
}

public partial class HelloWorldExample : MonoBehaviour, IEventReceiver<EventRegistrationAwake, EventDeregistrationOnApplicationQuit>
{
    [Listener]
    private void OnHelloWorld(OnHelloWorldEvent evnt)
    {
        Debug.Log(evnt.Message);
    }

    private void Start()
    {
        EventBus.Send(new OnHelloWorldEvent()
        {
            Message = "Hello World"
        });
    }
}

Explanation

There are several classes available for customizing when registration and de-registration happens of your listener methods. If you have a method already defined for these lifecycle methods (like Start() for example) you don't need to change your code at all. Behind the scenes the source generator will patch your Start() method to register the listeners before your code is ran.

The available options are:

Registration:

EventRegistrationAwake (when Awake() runs in the lifecycle)
EventRegistrationOnEnable (when OnEnable() runs in the lifecycle)
EventRegistrationStart (when Start() runs in the lifecycle)

Deregistration

EventDeregistrationOnApplicationQuit (when OnApplicationQuit() runs in the lifecycle)
EventDeregistrationOnDisable (when OnDisable() runs in the lifecycle)
EventDeregistrationOnDestroy (when OnDestroy() runs in the lifecycle)

Explanation​

Explanation