[SOLVED] Collision won't work

Hello, I'm sorry to post such newbi question, but I have a problem with my OnCollisionEnter2D function

So, I have an Enemy_Grunt (a polygon sprite) and a Player (a triangle sprite). Both have a box collider 2D for testing purposes. I inserted this piece of code in my PlayerController script:

Code (CSharp):

1.     private void OnCollisionEnter2D(Collision2D col)
2.     {
3.         if(col.gameObject.tag == "Enemy")
4.         {
5.             Destroy(this.transform.gameObject);
6.         }
7.     }

I have my Enemy_Grunt tagged with the "Enemy" tag, and I made sure that it was spelled correctly.

I actually wonder, what did I do wrong? Can someone help me, please?

 

Ok, so I managed to figure it out, noob mistake to miss the Rigidbody2D. But, Now, I'm running another problem with the Projectile.

I have this function in my Player controller which makes me fire up multiple instances of the projectile: (it is being called in the FixedUpdate method)

Code (CSharp):

1.     private void Shoot()
2.     {
3.  
4.         if(Input.GetButtonDown("Fire1"))
5.         {
6.             GameObject projectilePrefab;
7.  
8.             Vector2 mousePosition = Camera.main.ScreenToWorldPoint(Input.mousePosition);
9.             projectilePrefab = Instantiate(projectile, transform.position, Quaternion.Euler(0, 0, transform.eulerAngles.z)) as GameObject;
10.  
11.             Rigidbody2D projectileRigidBody = projectilePrefab.AddComponent<Rigidbody2D>();
12.             projectileRigidBody.velocity = mousePosition * projectileForce;
13.             projectileRigidBody.gravityScale = 0.0f;
14.         }
15.     }

I'm getting this error:

Code (CSharp):

1. Can't add component 'Rigidbody2D' to Projectile(Clone) because such a component is already added to the game object!
2. UnityEngine.GameObject:AddComponent()
3. PlayerController:Shoot() (at Assets/Scripts/PlayerController.cs:73)
4. PlayerController:FixedUpdate() (at Assets/Scripts/PlayerController.cs:25)

The line that is pointing me with the error is this one:

Code (CSharp):

1.             Rigidbody2D projectileRigidBody = projectilePrefab.AddComponent<Rigidbody2D>();

In the tutorial that I'm referencing this script of for my prototype, is working perfectly well. Someone could tell me why this is happening?

 

do you already have a rigidbody on the prefab?

 

In fact I did. I was adding 2 rigidbody2d's at the gameobject. I'm going to set this at solved. Thank you.