Problem with Null Reference Exception??

Question

So i have a script that activates a GUI when you press "e" on it. It's meant to pause the game when you are writing a "secret password" on the GUI. For this, i did the same that I have done with another script, I lock the camera, the movement of the character, the hability to turn the flash light on/off, etc. The problem only one thing is working, when i press "e" it gets displayed, but all the other variables that i want to transform into "false" are not responding... Here is the error:

NullReferenceException: Object reference not set to an instance of an object SafeLockOnE.Update () (at Assets/SafeLockOnE.js:38)

Here is the Script:

 var range: float = 5; 
 private var hit: RaycastHit;
 var SafeLockMeca : SafeLock;
 
 var lookAround01 : MouseLook;
 var lookAround02 : MouseLook;
 var charMotor : CharacterMotor;
 var charMotor2 : FPSWalkerEnhaced;
 var FlashlightHide : FlashLight;
 var HideCursor : HideMouseCursor;
 
 function Start ()  
 {
     SafeLockMeca = gameObject.GetComponent(SafeLock);
     
 
     lookAround01 = gameObject.GetComponent(MouseLook);
     lookAround02 = GameObject.Find("MainCamera").GetComponent(MouseLook);
     charMotor = gameObject.GetComponent(CharacterMotor);
     charMotor2 = gameObject.GetComponent(FPSWalkerEnhaced);
     FlashlightHide = GameObject.Find("FlashLight").GetComponent(FlashLight);
     HideCursor = GameObject.Find("Player").GetComponent(HideMouseCursor);
  
        SafeLockMeca.enabled = false;
  
 }
  
  
  
 function Update(){
  
   if (Input.GetKeyDown("e")){
     var ray = Camera.main.ViewportPointToRay(Vector3(0.5,0.5,0));
     if (Physics.Raycast(ray, hit, range)){
         SafeLockMeca.enabled = true;
  
         lookAround01.enabled = false;
         lookAround02.enabled = false;
         charMotor.enabled = false;
         charMotor2.enabled = false;
         FlashlightHide.enabled = false;
         HideCursor.enabled = false;
        
                     
   if (Input.GetKeyDown("KeyCode.Escape")){
 
         SafeLockMeca.enabled = false;
 
 
 }
 }
 }
 }

Tips: If i delete line 38, and everything that it's related to it, the next line does'nt work either, so only "SafeLockMeca.enabled = true;" it's working, from lookAround01.enabled = false; to HideCursor.enabled = false; is not working...:(

PS:

1) Also i don't know why but i discovered that the GUI with the password gets displayed also if i press "e" near any object with a collider...

2) I would also like if someone can show me a way to close the GUI when i press "ESC"

Answer 1

Which object is this script attached to? This code could get the right script instances only if all of them (including this script) were attached to the same object - the player, in this case. If this script (and SafeLock) are attached to a different object than the player, Start should be like this:

 function Start ()  
 {
     SafeLockMeca = GetComponent(SafeLock); // get SafeLock from this object
     var player = GameObject.Find("Player"); // get other scripts from the player
     lookAround01 = player.GetComponent(MouseLook);
     lookAround02 = Camera.main.GetComponent(MouseLook);
     charMotor = player.GetComponent(CharacterMotor);
     charMotor2 = player.GetComponent(FPSWalkerEnhaced);
     HideCursor = player.GetComponent(HideMouseCursor);
     // be careful: if there's more than one flashlight object
     // in scene, this line may return the wrong instance:
     FlashlightHide = GameObject.Find("FlashLight").GetComponent(FlashLight);
     SafeLockMeca.enabled = false;
 }

And the Raycast won't do what you expect, whatever it is: it checks for key E whenever any collider is in the middle of the screen and closer enough to the camera. What do you wanna do? Sense E when the mouse is over an existing GUIText or GUITexture? Or when the mouse is over the area where the GUI password should appear?

EDITED: Ok, so you want to enable the GUI code when the player is inside the trigger and E is pressed. You could use OnTriggerStay, but it's more efficient to have a boolean that tells whether the player has entered/exited the trigger. You should also monitor the current GUI state, and enable/disable the other scripts only when the GUI gets disabled/enabled - like this:

 private var inTrigger = false; // is player inside trigger?
 
 function OnTriggerEnter(other: Collider){
   if (other.CompareTag("Player")) inTrigger = true;
 }
 
 function OnTriggerExit(other: Collider){
   if (other.CompareTag("Player")) inTrigger = false;
 }
 
 private var guiEnabled = false; // current gui state
 
 function Update(){
   // if inside trigger and E pressed...
   if (inTrigger && Input.GetKey("e")){
     SafeLockMeca.enabled = true; // enable gui
   }
   // ESC disables gui
   if (Input.GetKey("escape")){ 
     SafeLockMeca.enabled = false;
   }
   // if GUI changed its enabled state...
   if (SafeLockMeca.enabled != guiEnabled){
     guiEnabled = SafeLockMeca.enabled; // update guiEnabled
     // disable/enable other scripts accordingly:
     lookAround01.enabled = !guiEnabled;
     lookAround02.enabled = !guiEnabled;
     charMotor.enabled = !guiEnabled;
     charMotor2.enabled = !guiEnabled;
     FlashlightHide.enabled = !guiEnabled;
     HideCursor.enabled = !guiEnabled;
   }    
 }

NOTE: In order to close the GUI when the correct password has been entered, just make SafeLock disable itself - for instance (SafeLock script):

 function OnGUI(){
   password = GUI.TextField (Rect (10, 10, 200, 20), password, 25);
   if (password == "cheat123"){
     enabled = false; // disable itself
   }
 }

The script in the trigger detects any change in SafeLock.enabled property and disables/enables the other scripts as needed.

Problem with Null Reference Exception??

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