Wave Spawner not working ｜Does not detect if an object is destroyed

Questions & Answers
1

Hey, I have a question regarding this script.
I have watched this tutorial several times but I can’t detect the error. Can someone help me?
The script is spawning 2 Enemies like i said it should do, but its not detecting if delete these Enemies.
I appreciate any answer. Thanks in advance!
Finn
Part 1

Part 2

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class WaveSpawner : MonoBehaviour {


    public enum SpawnState { Spawning, Waiting, Counting } // state of the Wave

    [System.Serializable]
    public class Wave
    {


        public string name; //wave name: Easy
        public Transform enemy; //Which Prefab should be spawned: Enemy
        public int count; //how much Enemys should be spawned per wave: 6
        public float rate; //how often the count of enemies should spawn

    }

    public Wave[] waves;
    private int nextWave = 0;

    public float timeBetweenWaves = 5f; //Time between waves: 5f = 5seconds
    public float waveCountdown; //time Counting down to next wave: 3... 2... 1...
    private float searchCountdown = 1f; // how long to search for alive enemies
    private SpawnState state = SpawnState.Counting;
    void Start()
    {
        waveCountdown = timeBetweenWaves;
    }

    void Update()
    {
        if (state == SpawnState.Waiting) //starts method to check if enemies are still alive
        {
            searchCountdown = 1f; //search countdown 1s
            if (!EnemyIsAlive())
            {
                //begin a new Wave
                Debug.Log("Wave Completed!");
                return;
            }
            else
            {
                return;
            }

        }




        if (waveCountdown <= 0) //ask if ready for new Wave
        {
            if (state != SpawnState.Spawning) //ask if Waves are already spawning
            {
                StartCoroutine( SpawnWave ( waves[nextWave] ) ); //start Spawning Routine
            }
        }
        else
        {
            waveCountdown -= Time.deltaTime; //if not count down
        }
    }

    bool EnemyIsAlive() //method to search for living enemies
    {
        searchCountdown -= Time.deltaTime; //count down search time
        if (searchCountdown <= 0f) //if search countdown = 0
        {
            if (GameObject.FindGameObjectWithTag("Enemy") == null) //check if enemy is alive
            {
                return false; //enemies arent allive
            }

        }
        return true; // enemies are allive
    }





    IEnumerator SpawnWave (Wave _wave) //Spawning Routine
    {
    Debug.Log("Spawning Wave: " + _wave.name);
        state = SpawnState.Spawning; //State: Spawning
        
        for (int i = 0; i < _wave.count; i++) //loop through amount of enemy
        {
            SpawnEnemy(_wave.enemy); //spawn enemy Method
            yield return new WaitForSeconds(1f / _wave.rate); //time between spawning of each enemy
        }
        state = SpawnState.Waiting; //State: Waiting
    yield break; //stop
    }

    void SpawnEnemy (Transform _enemy) //spawn enemy Method
    {
    Debug.Log("Spawning Enemy: " + _enemy.name);
    Instantiate(_enemy, transform.position, transform.rotation);
    }
}
2

I think EnemyIsAlive() is returning the wrong value, I’ve made some changes and adjustments, hope it helps.

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;

public class WaveSpawner: MonoBehaviour
{

    public enum SpawnState { Spawning, Waiting, Counting, Finished } // State of the wave

    [System.Serializable] public class Wave
    {
        public string name = "Easy";      // Wave name: Easy
        public Transform enemy = null;    // Which prefab should be spawned: Enemy
        public int count = 6;             // How much enemys should be spawned per wave: 6
        public float rate = 3;            // How often the count of enemies should spawn
    }

    public Wave[] waves = null;
    public float timeBetweenWaves = 5f;   // Time between waves: 5f = 5 seconds
    public int countdownFrom = 3;         // The number which countdown starts from
    public int waveCountdown = 0;         // Time Counting down to next wave: 3... 2... 1...

    private int waveIndex = 0;
    private int enemyIndex = 0;
    private float timer = 0;
    private SpawnState state = SpawnState.Counting;
    private string enemyTag = "Enemy";

    private void Start()
    {
        waveIndex = 0;
        enemyIndex = 0;
        state = SpawnState.Waiting;
        waveCountdown = 0;
        timer = 0;
        if(waves == null || waves.Length == 0)
        {
            state = SpawnState.Finished;
        }
    }

    void Update()
    {
        if(state == SpawnState.Finished)
        {
            return;
        }

        switch (state)
        {
            case SpawnState.Spawning:
                if(enemyIndex >= waves[waveIndex].count)
                {
                    enemyIndex = 0;
                    waveIndex++;
                    state = SpawnState.Waiting;
                    Debug.Log("Wave spawned.");
                    if (waveIndex < waves.Length)
                    {
                        Debug.Log("Waiting for the next wave.");
                    }
                    else
                    {
                        Debug.Log("That was the last wave.");
                    }
                }
                else
                {
                    if(timer >= waves[waveIndex].rate)
                    {
                        timer = 0;
                        waveCountdown = countdownFrom;
                        enemyIndex++;
                        SpawnEnemy(waves[waveIndex].enemy);
                    }
                    else
                    {
                        timer += Time.deltaTime;
                    }
                }
                break;
            case SpawnState.Waiting:
                if (waveIndex >= waves.Length)
                {
                    if (!EnemyIsAlive())
                    {
                        state = SpawnState.Finished;
                        Debug.Log("All Waves Completed. Level finished.");
                    }
                }
                else
                {
                    if (timer >= timeBetweenWaves)
                    {
                        timer = 0;
                        waveCountdown = countdownFrom;
                        state = SpawnState.Counting;
                        Debug.Log("Countdown started.");
                    }
                    else
                    {
                        timer += Time.deltaTime;
                    }
                }
                break;
            case SpawnState.Counting:
                if (timer >= countdownFrom)
                {
                    timer = 0;
                    waveCountdown = 0;
                    state = SpawnState.Spawning;
                    Debug.Log("Countdown finished. Spawning new wave.");
                }
                else
                {
                    timer += Time.deltaTime;
                    waveCountdown = countdownFrom - Mathf.FloorToInt(timer);
                }
                break;
        }
    }

    private bool EnemyIsAlive() // Method to search for living enemies
    {
        GameObject[] objects = GameObject.FindGameObjectsWithTag(enemyTag);
        return objects != null && objects.Length > 0;
    }
    
    private void SpawnEnemy(Transform _enemy) // Spawn enemy Method
    {
        Transform enemy = Instantiate(_enemy, transform.position, transform.rotation);
        enemy.tag = enemyTag;
        Debug.Log("Enemy spawned: " + _enemy.name);
    }

}