Unity Coroutine not working across scenes

问题

I am calling a Coroutine shown below, which is attached to a DontDestroyOnLoad objects that persists across scenes.

IEnumerator InitMaxScore()
{
    Debug.Log("will wait for some time");
    yield return new WaitForSeconds(1);
    GameObject[] coins = GameObject.FindGameObjectsWithTag("Coin");
    Debug.Log("coins length == " + coins.Length);
    if (coins.Length > 0)
    {
        maxScoreInitialized = true;
        maxScore = score + coins.Length * 10;
        foreach (GameObject healthPickup in GameObject.FindGameObjectsWithTag("Health"))
        {
            maxScore += healthPickup.GetComponent<Pickups>().pointsForLifePickup;
        }
        Debug.Log("maxScore inti == " + maxScore);
    }
    yield return null;
}

This Coroutine is called in the OnLevelWasLoaded event of the said gameobject which is set to DontDestroyOnLoad on awake as shown below.

private void Awake()
{
    int numGameSessions = FindObjectsOfType<GameSession>().Length;
    if (numGameSessions > 1)
    {
        Destroy(gameObject);
    }
    else
    {
        DifficultyManagement.setDifficulty(Difficulty.One); // start the game with diff one always
        DontDestroyOnLoad(this.gameObject);
    }
}

While the log "will wait for some time" in the Coroutine is getting printed, Debug.Log("coins length == " + coins.Length) is not getting printed all the times. I am certainly not destroying the said gameobject for the entire duration of my game that might have caused the Coroutine to behave this way. The behaviour is not consistent either, sometimes it works, sometimes it does not, and I am like why can't you make up your mind.

I have been banging my head on this for a long time and could not seem to fix this, any leads would be appreciated to lift my mental block :/

回答1:

OnLevelWasLoaded is deprecated, consider using sceneLoaded event:

using UnityEngine.SceneManagement;

private void Awake()
{
    int numGameSessions = FindObjectsOfType<GameSession>().Length;
    if (numGameSessions > 1)
    {
        Destroy(gameObject);
    }
    else
    {
        DifficultyManagement.setDifficulty(Difficulty.One); // start the game with diff one always
        DontDestroyOnLoad(this.gameObject);
        SceneManager.sceneLoaded += (scene, mode) => StartCoroutine(InitMaxScore());
    }
}

来源：https://stackoverflow.com/questions/55488344/unity-coroutine-not-working-across-scenes

标签

unity3d

coroutine