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Game Development How to Make a Video Game Pickups Spawn Pickups Randomly

UnassignedReferenceException: The variable flyPrefab of FlySpawner has not been assigned.

using System.Collections; using System.Collections.Generic; using UnityEngine;

public class FlySpawner : MonoBehaviour {

private GameObject flyPrefab;

private int totalFlyMinimum = 12;

private float spawnArea = 25f;

public static int totalFlies;

// Use this for initialization
void Start () {
    totalFlies = 0;

// Update is called once per frame
void Update () {

    //While the total number of flies is less than the minimum...
    while (totalFlies < totalFlyMinimum)
        //...then increment the total number of flies...

        //...create a random position for a fly
        float positionX = Random.Range(-spawnArea, spawnArea);
        float positionZ = Random.Range(-spawnArea, spawnArea);

        Vector3 flyPosition = new Vector3(positionX, 2f, positionZ);

        //...and create a new fly.
        Instantiate(flyPrefab, flyPosition, Quaternion.identity);



not sure why it is copying/pasting like that...if you need an email or a scrn shot let me know

1 Answer

Joel Brown
Joel Brown
4,590 Points

I could be wrong but if you go to Fly Spawner (Script) when clicking on Game Manager does it say "None" in the Fly Prefab? If so, click on the fly object under prefab in the asset window and drag it to that space. Hopefully this helps.