Assign a prefab in the inspector disappear when the game start

Unity Engine
1

Hi everybody

I can´t resolve this issue by myself. To sum up: I have a prefab shot, this prefab has a script of the behaviour of the shot called shot_behaviour, a sprite renderer, an animation and a 2DpoligonColider. Then, i have an item in the world called generator_shot, the generator shot has a public method of the shot_behavior type. In the inspector, i can assign without any problem:
2127497--139921--Befor_game_Start_inspector.png
However, when the game start, the prefab disappear from the inspector:

2127497--139922--After_game_Start_inspector.png
Obviosly, when i press the fire button, the console send a message error that cant find the item:

2127497--139923--Error_message.png
2127497--139923--Error_message.png933×32 5 KB

I tried resolve this issue in two ways:

  • Instead of create a prefab with that elements, I only create a cube element in the world, i assign to it the shot_behaviour, and then assigned to the gun_shoot_generator_behaviour, but also dissapear
  • The other form is create all the elements in the script gun_shoot_generator_Behaviour, but this method implies i cant reuse this elements and always have to be at the same form. I want to create different shot type depend on who shoot.

Can someone help my to resolve this?

Thank you in advance

2

Post your code please. From the looks of your screenshots, you haven’t assigned the prefab to a GameObject variable (or other variable, as applicable), so the script doesn’t know what you want to spawn. Just a guess, but a look at your code will tell us for sure.

1 Like
3

the shoot_Behaviour script:

using UnityEngine;
using System.Collections;

public class Shoot_Behaviour : MonoBehaviour {
    public float shoot_speed;
    public float live_shoot_time;

    void Start () {
        StartCoroutine ("live_until_destroy");
    }

    void Update () {
        this.transform.position = new Vector3 (this.transform.position.x, this.transform.position.y + (shoot_speed * Time.deltaTime), this.transform.position.z);
    }

    public IEnumerator live_until_destroy(){
        yield return new WaitForSeconds (live_shoot_time);
        Destroy (this.gameObject);
    }
}

and the gun_shoot_generator_behaviour

using UnityEngine;
using System.Collections;

public class Gun_Shoot_Generator_Behaviour : MonoBehaviour {

    public Shoot_Behaviour shoot_emiter;
    private AudioSource shoot_plasma_sound;
    private bool left_right_side_selected=false;
    public float separate_between_left_right_dual_guns = 0.86f;


    // Use this for initialization
    void Start() {
        shoot_emiter = this.gameObject.GetComponent <Shoot_Behaviour> ();
        shoot_plasma_sound = this.gameObject.GetComponent <AudioSource> ();
        NotificationCenter.DefaultCenter ().AddObserver (this, "Shoot_notification_receiver");
    }

    public void Shoot_notification_receiver(Notification notificacion){
        this.shoot_plasma_sound.Play ();
        Instantiate (shoot_emiter, this.gameObject.transform.position, Quaternion.identity);
        if (left_right_side_selected == false) {
            this.gameObject.transform.localPosition = new Vector3 (this.gameObject.transform.localPosition.x+separate_between_left_right_dual_guns, this.transform.localPosition.y, this.transform.localPosition.z);
            this.left_right_side_selected = true;
        } else {
            this.gameObject.transform.localPosition = new Vector3 (this.gameObject.transform.localPosition.x-separate_between_left_right_dual_guns, this.transform.localPosition.y, this.transform.localPosition.z);
            this.left_right_side_selected = false;
        }
    }
}
4

OK, in the “gun_shoot_generator_behaviour” script it looks like you’re trying to Instantiate shoot_emitter, but shoot_emitter looks to be a “Shoot_Behavior” script, not an actual game object. You’ll need to create an actual game object with that script on it, set it up as a prefab, alter the “gun_shoot_generator_behaviour” to know that it’s a game object, and then Instantiate that prefab instead…

1 Like
5

In the Start() function you are re-assigning shoot_emiter.

Unity propably doesn’t find it and therefore sets the public variable to null.

And this:

Instantiate (shoot_emiter, this.gameObject.transform.position, Quaternion.identity);

shouldn’t work this Instantiate usually takes a GameObject, not a script like Shoot_Behaviour.

1 Like
6

that is!!! thank you very much, i do that changes, and fix the problem

using UnityEngine;
using System.Collections;

public class Gun_Shoot_Generator_Behaviour : MonoBehaviour {

    public GameObject shoot_emiter;
    private AudioSource shoot_plasma_sound;
    private bool left_right_side_selected=false;
    public float separate_between_left_right_dual_guns = 0.86f;


    // Use this for initialization
    void Start() {
        //shoot_emiter = this.gameObject.GetComponent <GameObject> ();
        shoot_plasma_sound = this.gameObject.GetComponent <AudioSource> ();
        NotificationCenter.DefaultCenter ().AddObserver (this, "Shoot_notification_receiver");
    }

    public void Shoot_notification_receiver(Notification notificacion){
        this.shoot_plasma_sound.Play ();
        Shoot_Behaviour shot = Instantiate (shoot_emiter, this.gameObject.transform.position, Quaternion.identity) as Shoot_Behaviour;
        if (left_right_side_selected == false) {
            this.gameObject.transform.localPosition = new Vector3 (this.gameObject.transform.localPosition.x+separate_between_left_right_dual_guns, this.transform.localPosition.y, this.transform.localPosition.z);
            this.left_right_side_selected = true;
        } else {
            this.gameObject.transform.localPosition = new Vector3 (this.gameObject.transform.localPosition.x-separate_between_left_right_dual_guns, this.transform.localPosition.y, this.transform.localPosition.z);
            this.left_right_side_selected = false;
        }
    }
}
1 Like
7

Wonderful! So glad it worked out :slight_smile: Have fun & happy creating!

1 Like