Object Refernce not set to an instance of an object error.

Hello. I am extreamly new to coding, but as far as I can tell this script should work.

Code (CSharp):

1.    
2.     public class HeartsGUI2 : MonoBehaviour {
3.        
4.        
5.         public GameObject Player22;
6.        
7.         public GUITexture image2;
8.         public Texture2D Image_1;
9.         public Texture2D Image_2;
10.         public Texture2D Image_3;
11.         public Texture2D Image_4;
12.         public Texture2D Image_5;
13.         public Texture2D Image_6;
14.         public int hp = 5;
15.        
16.         public bool isEnemy = true;
17.         void Awake()
18.         {
19.             Player22 = GameObject.Find("Player2");
20.         }
21.        
22.        
23.        
24.         void Update()
25.         {
26.          if (Player22.GetComponent<Health>().hp == 5) {
27.                 image2.guiTexture.texture = Image_1;
28.             }
29.             if (Player22.GetComponent<Health>().hp == 4) {
30.                 image2.guiTexture.texture = Image_2;
31.             }
32.            
33.             if (Player22.GetComponent<Health>().hp == 3) {
34.                 image2.guiTexture.texture = Image_3;
35.             }
36.            
37.             if (Player22.GetComponent<Health>().hp == 2) {
38.                 image2.guiTexture.texture = Image_4;
39.             }
40.            
41.             if (Player22.GetComponent<Health>().hp == 1) {
42.                 image2.guiTexture.texture = Image_5;
43.             }
44.            
45.            
46.            
47.             if (Player22.GetComponent<Health>().hp <= 0) {
48.                 image2.guiTexture.texture = Image_6;
49.             }
50.            
51.            
52.            
53.            
54.             {
55.                
56.                
57.                
58.             }
59.         }
60.     }
61.    
62.    
63.    

Basically the code is supposed to change the image displayed on a hearts GUI every time Player2 is shot to show how much health it has left. I made the same code referencing my Player1 and it works fine but when I copy pasted it over and renamed everything it no longer worked. Unity came up with an enormous amount of errors all saying the same thing. NullReferenceException: Object reference not set to an instance of an object
HeartsGUI2.Update () (at Assets/Scripts/HeartsGUI2.cs:28). Please help. Thank you.

 

Add

Code (CSharp):

1. if(!player22)
2. {
3. Debug.LogError("Couldn't find Player 2");
4. }

inside your Awake function after you try to assign Player22. If this shows in the console as an error, the gameobject "Player2" is not in the scene

 

Ok I am an idiot for not noticing I accidentally named it Player 2 instead of Player2. The script still isn't working though although it now shows no errors. I don't understand why it doesn't work here but does on Player1. I will post my first script. See if you can find what the difference is between the 2. Thank you.

Code (CSharp):

1. using System.Collections;
2.  
3. public class HeartsGUI : MonoBehaviour {
4.  
5.  
6.     public GameObject Player1;
7.  
8.         public GUITexture image;
9.         public Texture2D Image_01;
10.         public Texture2D Image_02;
11.         public Texture2D Image_03;
12.         public Texture2D Image_04;
13.         public Texture2D Image_05;
14.         public Texture2D Image_06;
15.         public int hp = 5;
16.      
17.         public bool isEnemy = true;
18.     void Awake()
19.     {
20.         Player1 = GameObject.Find("Player");
21.     }
22.      
23.  
24.  
25.     void Update()
26.     {
27.         if (Player1.GetComponent<Health>().hp == 5) {
28.                         image.guiTexture.texture = Image_01;
29.                     }
30.         if (Player1.GetComponent<Health>().hp == 4) {
31.                         image.guiTexture.texture = Image_02;
32.                     }
33.                  
34.         if (Player1.GetComponent<Health>().hp == 3) {
35.                         image.guiTexture.texture = Image_03;
36.                     }
37.                  
38.         if (Player1.GetComponent<Health>().hp == 2) {
39.                         image.guiTexture.texture = Image_04;
40.                     }
41.                  
42.         if (Player1.GetComponent<Health>().hp == 1) {
43.                         image.guiTexture.texture = Image_05;
44.                     }
45.                  
46.                  
47.                  
48.         if (Player1.GetComponent<Health>().hp <= 0) {
49.                         image.guiTexture.texture = Image_06;
50.                 }
51.                      
52.                      
53.                      
54.                      
55.                         {
56.                          
57.                          
58.                          
59.                         }
60.                     }
61.                 }
62.      
63.              
64.        

 

Probably the Health component is not attached to your player2.
Just so you're aware also, you can store a reference to your Health component on Awake() also. Which will clean your code up a bit.

Code (CSharp):

1. using System.Collections;
2. public class HeartsGUI : MonoBehaviour {
3.     public GameObject Player1;
4.       private Health m_health;
5.         public GUITexture image;
6.         public Texture2D Image_01;
7.         public Texture2D Image_02;
8.         public Texture2D Image_03;
9.         public Texture2D Image_04;
10.         public Texture2D Image_05;
11.         public Texture2D Image_06;
12.         public int hp = 5;
13.  
14.         public bool isEnemy = true;
15.     void Awake()
16.     {
17.         Player1 = GameObject.Find("Player");
18.        m_health = Player1.GetComponent<Health>();
19.        if(!m_health)
20.        {
21.         Debug.LogError("Health component not attached");
22.        }
23.     }
24.  
25.     void Update()
26.     {
27.        if (m_health.hp == 5) {
28.                         image.guiTexture.texture = Image_01;
29.                     }
30.         if (m_health.hp == 4) {
31.                         image.guiTexture.texture = Image_02;
32.                     }
33.              
34.         if (m_health.hp == 3) {
35.                         image.guiTexture.texture = Image_03;
36.                     }
37.              
38.         if (m_health.hp == 2) {
39.                         image.guiTexture.texture = Image_04;
40.                     }
41.              
42.         if (m_health.hp == 1) {
43.                         image.guiTexture.texture = Image_05;
44.                     }
45.              
46.              
47.              
48.         if (m_health.hp <= 0) {
49.                         image.guiTexture.texture = Image_06;
50.                 }
51.                  
52.                  
53.                  
54.                  
55.                         {
56.                      
57.                      
58.                      
59.                         }
60.                     }
61.                 }
62.  
63.          
64.        

Also, are all of your Image_ the same texture? Are you just trying to draw a heart for every hp you have?

 

No. I have 6 images that I want to show on the GUI Texture depending on the health. My Health script is attached to player2 as well. I got the script to work now. Thank you for your help

 

How are you drawing them? Maybe they are positioned on top of each other so it looks like only 1 set is drawing.

Your code design is also not great. You should really only have 1 HeartsGUI component. Then your player class would reference this and feed it it's own health. When I get back from work I may give you an example code.