render cube problem

when i make this script

Code (csharp):

1. var nxtlvl : boolean = false;
2.  
3.  
4.  
5. function React ()
6.  
7. {
8.     nxtlvl = true;
9. }
10.  
11. function Update ()
12. {
13.     if(nxtlvl)
14.     {
15.     GetComponent (MeshRenderer);
16.     }
17. }

i know the boolean works but the getcomponent doesn't work because i need a cube to render any ideas?