Unity Crashes when using this script (NullReference?!)

i wanted to make an arkanoid 2d game that instantiate balls every 5 seconds and when it instantiates, waits 1 second and then falls to the ground. here are the ball and ballSpawner Script:

Code (CSharp):

1. using System.Collections;
2. using System.Collections.Generic;
3. using UnityEngine;
4. using System;
5.  
6. public class Ball : MonoBehaviour
7. {
8.  
9.     Rigidbody2D rb2d;
10.     float startAngle = 20f;
11.  
12.     Timer ballDeathTimer;
13.     BallSpawner ballSpawner;
14.     Timer addForceTimer;
15.     bool deadInScreen = false;
16.     Vector2 colliderLowerLeft;
17.     Vector2 colliderUpperRight;
18.    
19.     // Start is called before the first frame update
20.     void Start()
21.     {
22.        
23.  
24.        
25.        
26.         ballSpawner = Camera.main.GetComponent<BallSpawner>();
27.  
28.        ballDeathTimer = gameObject.AddComponent<Timer>();
29.         ballDeathTimer.Duration = ConfigurationUtils.BallLifeTime;
30.         ballDeathTimer.Run();
31.  
32.         addForceTimer = gameObject.AddComponent<Timer>();
33.         addForceTimer.Duration = 1f;
34.         addForceTimer.Run();
35.      
36.      
37.     }
38.  
39.    
40.  
41.     public void SetDirection(Vector2 direction)
42.     {
43.  
44.         rb2d.velocity = - direction * rb2d.velocity.magnitude;
45.     }
46.     // Update is called once per frame
47.     void Update()
48.     {
49.      
50.             if (addForceTimer.Finished)
51.             {
52.                 AddForceToBall();
53.                 RestoreForceTimer();
54.             }
55.        
56.  
57.        
58.         if(ballDeathTimer.Finished)
59.         {
60.             Destroy(gameObject);
61.             deadInScreen = true;
62.             ballSpawner.SpawnABall();
63.             addForceTimer.Run();
64.          
65.         }
66.  
67.        
68.     }
69.  
70.     void AddForceToBall()
71.     {
72.         float startAngleRadian = 270 * Mathf.Deg2Rad;
73.         Vector2 vectorForce = new Vector2(Mathf.Cos(startAngleRadian), Mathf.Sin(startAngleRadian));
74.  
75.         rb2d = GetComponent<Rigidbody2D>();
76.         rb2d.AddForce(vectorForce * ConfigurationUtils.BallImpulseForce);
77.     }
78.  
79.     void RestoreForceTimer()
80.     {
81.         Destroy(addForceTimer);
82.         addForceTimer = gameObject.AddComponent<Timer>();
83.         addForceTimer.Duration = 1f;
84.     }
85.     private void OnBecameInvisible()
86.     {
87.         if (!deadInScreen)
88.         {
89.             Destroy(gameObject);
90.            // ballSpawner.SpawnABall();
91.             RestoreForceTimer();
92.  
93.         }
94.     }
95.  
96.  
97.    
98. }
99.  

Code (CSharp):

1. using System.Collections;
2. using System.Collections.Generic;
3. using UnityEngine;
4.  
5. public class BallSpawner : MonoBehaviour
6. {
7.  
8.     [SerializeField]
9.     GameObject ball;
10.  
11.  
12.  
13.     Timer spawnSeconds;
14.    
15.     float spawnX, spawnY;
16.     BoxCollider2D boxCol2D;
17.     Vector2 colliderLowerLeft;
18.     Vector2 colliderUpperRight;
19.    
20.  
21.  
22.     private void Start()
23.     {
24.        
25.         GameObject ballTemp = Instantiate(ball, Vector3.zero, Quaternion.identity);
26.         boxCol2D = ballTemp.GetComponent<BoxCollider2D>();
27.         colliderLowerLeft = (Vector2)transform.position - new Vector2(boxCol2D.size.x/2, boxCol2D.size.y/2);
28.         colliderUpperRight = (Vector2)transform.position + new Vector2(boxCol2D.size.x/2, boxCol2D.size.y/2);
29.         Destroy(ballTemp);
30.  
31.      
32.  
33.         spawnSeconds = gameObject.AddComponent<Timer>();
34.         spawnSeconds.Duration = Random.Range(ConfigurationUtils.MinSpawnSecond,ConfigurationUtils.MaxSpawnSecond);
35.         spawnSeconds.Run();
36.        
37.        
38.     }
39.    
40.  
41.     private void Update()
42.     {
43.        if(spawnSeconds.Finished)
44.         {
45.             SpawnABall();
46.            
47.            
48.         }
49.  
50.      
51.     }
52.  
53.  
54.     public void SpawnABall()
55.     {
56.  
57.            
58.         GameObject ballSpawn = Instantiate(ball,RandomPosition(), Quaternion.identity);
59.         while(Physics2D.OverlapArea(colliderLowerLeft, colliderUpperRight) != null)
60.         {
61.             Destroy(ballSpawn);
62.             ballSpawn = Instantiate(ball, RandomPosition(), Quaternion.identity);
63.             Debug.Log("trying again!");
64.         }
65.  
66.              
67.     }
68.  
69.     Vector2 RandomPosition()
70.     {
71.         spawnX = Random.Range(ScreenUtils.ScreenLeft, ScreenUtils.ScreenRight);
72.         spawnY = Random.Range(ScreenUtils.ScreenBottom, ScreenUtils.ScreenTop);
73.  
74.         Vector2 positionSpawn = new Vector2(spawnX, spawnY);
75.  
76.         return positionSpawn;
77.     }
78.  
79.  
80.    
81. }

please use my code for a circle and try if you want. i get null Reference for timers, and the timer script is something standard i used it a lot. when it runs unity hangs, when opening task manager memory consumptions rise up every second and says its not responding.

 

What is the exact error and line number? You can use Debug.Log to determine if an object is null during a debug session.

 

Code (CSharp):

1.    if (addForceTimer.Finished)
2.             {
3.                 AddForceToBall();
4.                 RestoreForceTimer();
5.             }

the if line, i get nullreferenece in every update execution. but now it just crashes.and i cant debug anymore.

 

Ok i just used a ball object and debug.log and i figured out that the problem is not timer; but in an instant a whole lot of ball just instantiates one after another like crazy and it crashes unity

 

ok i found out the proble, thanks a lot jeff that sentence you told me about debug.log was just something i knew but it gave me insight into my problem.
when timer finishes it should run again but i forgot to write that line. a simple line wasted my goddamn 3 days.

 

well that piece of code is for finding collision-free space in screen. if you spawn a ball in a place there is another ball it just spawns another ball in a random place. it does not cause problem i tested it in a different scene and it worked fine.

do you have any advice for that?

and no im not saying its unity's fault maybe i posted in a wrong place, i certainly knew it was my problem. im new here.if im in a same problem, where should i post it?