Make Unity add it for you.
The problem
Assuming it's there.
public class Mover : MonoBehaviour{ void Start() { GetComponent<Rigidbody>().useGravity = false; }}
No Rigidbody on the GameObject? GetComponent returns null and this line throws.
The fix
Declare what you need.
[RequireComponent] tells Unity this script can't work without another component.
[RequireComponent]→added automatically
The fix in code
One attribute.
[RequireComponent( typeof( Rigidbody ) )]public class Mover : MonoBehaviour{ void Start() { GetComponent<Rigidbody>().useGravity = false; }}
Add Mover and Unity adds a Rigidbody too. It won't let you remove it while Mover needs it.
Watch out
It only runs when you add the script.
Objects that already had Mover before you added the attribute won't get a Rigidbody.
- New objects
- component added ✓
- Existing objects
- re-add the script
The rule
Declare dependencies. Skip the null checks.
- Needs a component
- [RequireComponent]
- Unity adds it
- with the script
- Old objects
- re-add the script