IEnumerator OnCollisionEnter2D not waiting-CodePudding

I am trying to set a gameobject to active on collision, wait a second and then set it to inactive again, but after the WaitForSeconds() line the execution seems to stop. I have no experience with C# and Unity so this may be a beginner mistake. Any idea why this could be happening?

private IEnumerator OnCollisionEnter2D(Collision2D collidedWith) {
        
        if (collidedWith.gameObject.tag == "Shape") {
            collidedWith.transform.GetChild(0).gameObject.SetActive(true);
            Object.Destroy(this.gameObject);
            yield return new WaitForSeconds(1);
            Debug.Log("Should have waited for 1 second");
            collidedWith.transform.GetChild(0).gameObject.SetActive(false);
        }
}

CodePudding user response：

You do

Object.Destroy(this.gameObject);

on this object which is running the Coroutine -> The routine is interrupted in that very same moment (when it reaches the first yield statement) -> it never actually starts to wait ;)

You should rather have a component on the object you collide with and make sure the Coroutine is run on that one instead.

E.g. like

// Have this on your Shape objects
public class Shape : MonoBehaviour
{
    private bool isCollided;

    public void Collided()
    {
        if(!isCollided) StartCoroutine(Routine());
    }

    private IEnumerator Routine()
    {
        if(isCollided) yield break;

        isCollided = true;

        var child = transform.GetChild(0).gameObject;
        
        child .SetActive(true);
        yield return new WaitForSeconds(1);
        child.SetActive(false);

        isCollided = false;
    }
}

and then rather do e.g.

private void OnCollisionEnter2D(Collision2D collidedWith) 
{
    if (collidedWith.gameObject.TryGetComponent<Shape>(out var shape)) 
    {
        shape.Collided();
        Destroy(gameObject);
    }
}