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i want to get a component value from the game object which collides with my trigger's object script. this is my code on the trigger:

 void OnTriggerEnter (Collider obj){
     if(obj.GetComponent<motor>().enabled == true){
         passed = true;
     }
 }

and this is the error i get:

NullReferenceException: Object reference not set to an instance of an object
 cp.OnTriggerEnter (UnityEngine.Collider obj) (at Assets/Scripts/cp.cs:15)

also when changing the code on the trigger:

 motor mObj = obj.gameObject.GetComponent();
    if(mObj != null){
         //code here
         Debug.Log("mObj not null");
     }else{
             Debug.Log("mObj is null");
     }

it returns

mObj is null

but the parent obj does have that 'motor' script, other scripts in the car which enter the trigger can access it

share|improve this question
    
<motor> is case sensitive? –  dnk drone.vs.drones Aug 25 at 13:02
    
the script name is all lowercase @dnkdrone.vs.drones –  Bill Bodkin Aug 25 at 13:03
    
try "motor m = obj.GetComponent<motor>();" –  dnk drone.vs.drones Aug 25 at 13:05
    
tred that: 'code' motor mObj = obj.gameObject.GetComponent(); if(mObj != null){ //code here Debug.Log("mObj not null"); }else{ Debug.Log("mObj is null"); } 'code' returned 'code' mObj is null 'code' –  Bill Bodkin Aug 25 at 13:09

2 Answers 2

up vote 0 down vote

i found that it must be the wheel collides or some other child causing the issue anyway here is the code i now use

    void OnTriggerEnter (Collider obj){


    motor mObj = obj.transform.parent.gameObject.GetComponent<motor>();
    if(mObj != null){
        //code here
        Debug.Log("mObj not null");
        if(mObj.enabled == true){
            Debug.Log("cp passed");
        passed = true;
        }
    }else{
        Debug.Log("mObj is null");
    }

}

thank you for helping

share|improve this answer
    
No probs :)...... –  Hash Buoy Aug 25 at 16:11
up vote 0 down vote

Make the following changes to the code.

    motor mObj = obj.gameObject.GetComponent<motor>(); 
    if(mObj != null){
         //code here
         Debug.Log("mObj not null");
     }else{
             Debug.Log("mObj is null");
     }

On trigger will only work if the game object to which this script is attached have a collider. It won't work if only the children have colliders.

share|improve this answer
    
returns "mObj is null" –  Bill Bodkin Aug 25 at 13:12
    
the object to enter the trigger is a car with only a colder on its body (currently just a cube) and wheel collides, would the wheel collides be the issue? –  Bill Bodkin Aug 25 at 13:16

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