How can I add randomly instantiated gameobjects to a list?

I'm trying to generate randomly selected enemies in a room.

The catch is I need the instantiated enemy gameobjects to be added to my Enemies list. This is because I need to count how many enemies are left to open the doors of the room.

Here's what I've got for the enemy counter:

Code (CSharp):

1. using System.Collections;
2. using System.Collections.Generic;
3. using UnityEngine;
4.  
5. public class RoomCenter : MonoBehaviour
6. {
7.     public bool openWhenEnemiesCleared;
8.  
9.     public List<GameObject> enemies = new List<GameObject>();
10.  
11.     public Room theRoom;
12.  
13.     // Start is called before the first frame update
14.     void Start()
15.     {
16.         if (openWhenEnemiesCleared)
17.         {
18.             theRoom.closeWhenEntered = true;
19.         }
20.     }
21.  
22.     // Update is called once per frame
23.     void Update()
24.     {
25.         if (enemies.Count > 0 && theRoom.roomActive && openWhenEnemiesCleared)
26.         {
27.             for (int i = 0; i < enemies.Count; i++)
28.             {
29.                 if (enemies[i] == null)
30.                 {
31.                     enemies.RemoveAt(i);
32.                     i--;
33.                 }
34.             }
35.  
36.             if (enemies.Count == 0)
37.             {
38.                 theRoom.OpenDoors();
39.             }
40.  
41.         }
42.     }
43. }
44.  

And this is what I'm looking to create for my random enemy spawner:

Code (CSharp):

1. using System.Collections;
2. using System.Collections.Generic;
3. using UnityEngine;
4.  
5. public class MonstersSpawnerControl : MonoBehaviour {
6.  
7.     public Transform[] spawnPoints;
8.     public GameObject[] monsters;
9.     int randomSpawnPoint, randomMonster;
10.     public static bool spawnAllowed;
11.  
12.     // Use this for initialization
13.     void Start () {
14.         spawnAllowed = true;
15.         InvokeRepeating ("SpawnAMonster", 0f, 1f);
16.     }
17.  
18.     void SpawnAMonster()
19.     {
20.         if (spawnAllowed) {
21.             randomSpawnPoint = Random.Range (0, spawnPoints.Length);
22.             randomMonster = Random.Range (0, monsters.Length);
23.             Instantiate (monsters [randomMonster], spawnPoints [randomSpawnPoint].position,
24.                 Quaternion.identity);
25.         }
26.     }
27.  
28. }
29.  

So my question is how to add the instantiated gameobjects from the "monsters" array into the "enemies" list.


TLDR - I want to add instantiated enemy gameobjects to my Enemies list.

 

In RoomCenter.cs

Code (csharp):

1. public void AddEnemyToList(GameObject newEnemy)
2. {
3. enemies.Add(newEnemy);
4. }

In MonstersSpawnerControl, change line 23 to

Code (csharp):

1. GameObject spawnedEnemy = Instantiate(monsters[randomMonster], spawnPoints[randomSpawnPoint].position, Quaternion.identity);
2. roomCenter.AddEnemyToList(spawnedEnemy);

You'll need to declare a new variable at the top to cache the reference to RoomCenter.

Code (csharp):

1. private RoomCenter roomCenter;
2.  
3. private void Start()
4. {
5. roomCenter = FindObjectOfType<RoomCenter>();
6. }

 

Ok, YOU are a genius!

One issue I'm encountering -- it seems the enemies are instantiating at spawn points every second. I'm a little new to InvokeRepeating, but I'm wondering if it's the right thing. I only want one enemy to spawn once, and that's it.

Any tips?

 

Actually it seems I have figured it out.

I just used SpawnEnemy() instead of InvokeRepeating.

I also changed the private RoomCenter roomcenter to public, and just made sure I connected in the inspector. Looks like it's working for now! I'll check back if I encounter another issue.

Thank you!

 

If you're doing it that way, make sure to remove the line from Start(), otherwise it will overwrite what you assign.

 

Done, thanks!