Question Help fixing 'variable not assigned' error

Hi,

This code works, but it pumps out non-gamebreaking errors during play. It's "The variable JumpingPlatform of JumpCollisionDetector has not been assigned."

The line throwing the error is Line 23: if (JumpingPlatform.CompareTag("JumpingPlatform") && (EnteredTrigger == true))

Can someone please help me modify the code to stop the error? As I said, it doesn't affect the game, but I'm not a good enough coder to fix it myself.

Thanks kindly!

Code (CSharp):

1. using System.Collections;
2. using System.Collections.Generic;
3. using UnityEngine;
4.  
5. public class JumpCollisionDetector : MonoBehaviour
6. {
7.     public bool EnteredTrigger;
8.     public GameObject JumpingPlatform;
9.  
10.     public void OnTriggerEnter(Collider col)
11.     {
12.         if (col.gameObject.CompareTag("JumpingPlatform"))
13.         {
14.             EnteredTrigger = true;
15.             JumpingPlatform = col.gameObject;
16.             JumpingPlatform.GetComponent<Collider>().isTrigger = true;
17.         }
18.     }
19.  
20.     IEnumerator OnTriggerExit(Collider col)
21.     {
22.  
23.         if (JumpingPlatform.CompareTag("JumpingPlatform") && (EnteredTrigger == true)) --- ERROR
24.          {
25.             yield return new WaitForSeconds(.3f);
26.             EnteredTrigger = false;
27.             JumpingPlatform.GetComponent<Collider>().isTrigger = false;
28.         }
29.     }
30. }
31.  

 

How to fix a NullReferenceException error

https://forum.unity.com/threads/how-to-fix-a-nullreferenceexception-error.1230297/

Three steps to success:
- Identify what is null <-- any other action taken before this step is WASTED TIME
- Identify why it is null
- Fix that

 

Thanks.

Honestly, I've come a long way this year...from not scripting, to scripting! Admittedly, it's been difficult and I'm not very good. I've tried working out why...several times. I honestly just need some help.

 

Have assigned your public variable JumpingPlatform in the inspector?

 

It gets assigned when it detects a viable platform. So I don't assign the public variable manually...it gets done runtime.

A quick explanation...the script attaches to an object parented to the player to detect platforms above the player.

 

Then either one of two things needs to be true:

1) you must guarantee enter gets hit BEFORE exit and that the code runs as expected,

OR

2) you need to check if it is null before trying to use it.

 

As you are calling this on the OnTriggerExit callback, I am guessing the variable is not assigned at that time. If it is working fine just do

Code (CSharp):

1. if(JumpingPlatform == null) return;

on line 22

 

Return didn't do it, but Yield break did

Many thanks to you both for helping me along.

 

My bad, missed you were in a IEnumerator, must sleep