我正在制作一款TurnBased游戏，我想使用协程来控制游戏流程。
为什么我添加了“yield return null”，游戏正常，当我去掉“yield return null”后，游戏就抛出异常
这是BattleRole中的错误代码
public IEnumerator ActionRoutine(){
yield return new WaitForSeconds(1f);
Debug.Log(gameObject + " Action Done!");
IamDead();
//yield return null; // Have thie one line will no error, else cause error
}
public void IamDead(){
OnDead?.Invoke(this, EventArgs.Empty);
Destroy(gameObject);
}
错误信息
MissingReferenceException: The object of type 'BattleRole' has been destroyed but you are still trying to access it.
Your script should either check if it is null or you should not destroy the object.
BattleRole+\<ActionRoutine\>d__19.MoveNext () (at Assets/Scripts/Player/BattleRole.cs:58)
UnityEngine.SetupCoroutine.InvokeMoveNext (System.Collections.IEnumerator enumerator, System.IntPtr returnValueAddress) (at \<f712b1dc50b4468388b9c5f95d0d0eaf\>:0)
这是我的 TurnBasedManager：
using System;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
[RequireComponent(typeof(LevelManager))]
public class TurnBasedManager : Singleton<TurnBasedManager>
{
public event EventHandler OnTurnStart;
// turn Gaming is a flag that point out if the turn based cycle is done
private bool turnGaming = true;
private bool isTurnEnd = false;
private void Start() {
StartCoroutine(MainCoroutine());
RoleManager.Instance.OnNoRoleAlive += (_, _) => {
turnGaming = false;
};
RoleManager.Instance.OnActionsDone += (_, _) => {
isTurnEnd = true;
};
}
// The Main Corotine that turn based have
private IEnumerator MainCoroutine(){
// Init the game
yield return InitGame();
// Start run the Turn based logic
yield return TurnBasedCycle();
}
// I think there is no the key that cause problem
private IEnumerator InitGame(){
// Init the scene
LevelManager.Instance.LoadSceneInfo();
// Sign up all the BattleRole in Scene
yield return RoleManager.Instance.InitRoles();
}
private IEnumerator TurnBasedCycle(){
// One while cycle is one Turn in game
while(turnGaming){
isTurnEnd = false;
OnTurnStart?.Invoke(this, EventArgs.Empty);
BattleRole nextRole;
while((nextRole = RoleManager.Instance.GetNextActionRole()) != null){
// Wait until the role action done
yield return nextRole.ActionRoutine();
}
if (isTurnEnd){
// Tell the RoleManager to update the action order of roles
RoleManager.Instance.UpdateActionOrder();
}
}
yield return null;
}
}
这是我的角色管理器
using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
using UnityEngine;
public class RoleManager : Singleton<RoleManager>
{
// OnActionsDone is Invoke when all role's action done
public event EventHandler OnActionsDone;
public event EventHandler OnNoRoleAlive;
// Use Linked list to define action queue, because roles may die
private LinkedList<BattleRole> actionQueue = new LinkedList<BattleRole>();
// The "head" and "end" is two sentinels
private LinkedListNode<BattleRole> currentActionNode, head = new(null), end = new(null);
private List<BattleRole> allRoles = new List<BattleRole>();
public IEnumerator InitRoles(){
// Wait one frame till all the role Inited
yield return null;
}
private void Start() {
TurnBasedManager.Instance.OnTurnStart += (_, _) => {
UpdateActionOrder();
};
}
public void AddOneRole(BattleRole role){
if (!allRoles.Contains(role)){
allRoles.Add(role);
role.OnDead += (_, _) => {
allRoles.Remove(role);
// Can not delete role node in actionQueue, because "role" may be the current actino role
};
}
}
public List<BattleRole> GetEnemies(){
return allRoles.Where(entry => entry.IsFriend == false).ToList();
}
public List<BattleRole> GetFriends(){
return allRoles.Where(entry => entry.IsFriend == true).ToList();
}
public void UpdateActionOrder(){
actionQueue.Clear();
var orderedRoles = allRoles.OrderByDescending(entry => entry.Param.agi);
foreach (var role in orderedRoles)
{
actionQueue.AddLast(role);
}
actionQueue.AddFirst(head);
actionQueue.AddLast(end);
currentActionNode = head;
}
// Get the next Action Role
public BattleRole GetNextActionRole(){
// Onle sentinels in queue, so there is no alives, invoke the event
if (actionQueue.Count <= 2){
OnNoRoleAlive?.Invoke(this, EventArgs.Empty);
return null;
}
while(currentActionNode == head ||
(currentActionNode != end && currentActionNode.Value.IsDead)){
currentActionNode = currentActionNode.Next;
}
if(currentActionNode == end){
OnActionsDone?.Invoke(this, EventArgs.Empty);
}
return currentActionNode.Value;
}
}
这是我的战斗角色
using System;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
// Something like HP, agi,
[Serializable]
public class RoleParameter{
...
}
//
public class BattleRole : MonoBehaviour
{
public event EventHandler OnDead;
[SerializeField]
private RoleParameter param;
/*
Something does not matter I think
...
*/
private void Start() {
// Sign up self to RoleManager
RoleManager.Instance.AddOneRole(this);
}
// The routine that action
public IEnumerator ActionRoutine(){
yield return new WaitForSeconds(1f);
Debug.Log(gameObject + " Action Done!");
IamDead();
// yield return null // If have no this line code, will cause error
}
public void IamDead(){
OnDead?.Invoke(this, EventArgs.Empty);
Destroy(gameObject);
}
}
我期望回合制游戏运行，每个角色在其动作完成后都会摧毁自己，直到所有角色都被摧毁。
我尝试添加和删除该行“yield return null”，添加“yield return null”将正常运行，但是如果我删除该行，它将破坏第一个角色并且不再进行处理，任何人都可以告诉我为什么？
这部分：
while((nextRole = RoleManager.Instance.GetNextActionRole()) != null){
// Wait until the role action done
yield return nextRole.ActionRoutine();
}
如果没有这一行，你会在销毁当前角色后立即检索下一个角色，尽管我不知道
IsDeadif(!currentRole)if(currentRole == null)