Instantiate Prefab from within class

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1

I’m having a bit of difficulty figuring this out, but I think I am overlooking something simple.

I had my script for a level generator which would instantiate prefabs to build the level. It followed this pattern, just in the root of the .js file which I attached to a blank object in the scene.

public var wall : Transform;

function Start () {
	for (var x = 0; x < 10; x++){
		var newTile : Transform;
		newTile = wall;
		var instTile : Transform = Instantiate(newTile, Vector3(x, 0,0),Quaternion.identity);
	}
}

At which point I drag the prefab onto the script variables area in the Inspector.

However, I want to create a class that will do the instantiating. I know that I need to use GameObject.Instantiate, but my issue comes from not having the Prefabs available within the class.

If I create a class and try to access the prefabs, it says it cannot recognize the prefabs.

Here is an example of what I was trying using classes:

public var wall : Transform;

    class area{
    	
    	function area(){
    		var newTile : Transform;
            	newTile = wall;
            	var instTile : Transform = GameObject.Instantiate(newTile, Vector3(x, 0,0),Quaternion.identity);
    	}
    
    }
    
    function start(){
    
    	var currentZone = new area();
    
    }

Which tells me that there is no such object as “wall”. If I declare the prefabs within the class, I can no longer drag them onto the script in the Inspector Panel.

Am I missing something obvious here?

2 Answers

2
2

There is two ways to spawn some prefab on the fly.

First one :
Use a list of public members which describe each prefab you need for your level and spawn them in the start or awake function. For example (sorry, but I can’t write js script… I hope you are able to translate C#):

public class LevelLoader : MonoBehavior
{
  public Transform WallPrefab;
  public Transform EnnemyPrefab;

  protected void Start()
  {
    GameObject wallObject1 = GameObject.Instanciate(this.WallPrefab);
    GameObject wallObject2 = GameObject.Instanciate(this.WallPrefab);
  
    // ...
  }
}

Or you can use the Resources.Load() method. Put your wall prefab in the Resources folder and then use the load function to instanciate your prefab.

Hope it’s helped…

cheers,
Thor

3

As far as I understand, an inner class is not able to access the outer class’ variables implicitly in UnityScript.
You can access them by supplying the outer instance explicitly, it’s not so elegant though.

Here’s a fixed script:

public var wall : Transform;

class area{
    var outer;
    function area(_outer) {
        outer = _outer;
        var newTile : Transform;
        newTile = outer.wall;
        var instTile : Transform = GameObject.Instantiate(newTile, Vector3(0, 0,0),Quaternion.identity);
    }

}

function Start(){

    var currentZone = new area(this);
    
}