How to Load a list or ienumerable of AssetReference with standart asynchronous operation handler?

Is there a built-in way to load list of AssetReferences or List Of AssetAddress with standart operation handler?

I can write something like

Code (CSharp):

1.  
2.     public IEnumerator LoadAll( List<AssetReference> assets , Action completed)
3.     {
4.        
5.         Debug.Log("Started");
6.         var tStart = Time.realtimeSinceStartup;
7.        
8.         var completionindex = 0;
9.         foreach (var assetReference in assets)
10.         {
11.             assetReference.LoadAssetAsync<Object>().Completed +=
12.                   handle => completionindex += 1;
13.         }
14.  
15.         yield return new WaitUntil(()=> completionindex == assets.Count);
16.        
17.         //completed?.Invoke();
18.         var tEnd = Time.realtimeSinceStartup;
19.  
20.         Debug.Log("Completed");
21.         Debug.Log(tEnd - tStart);
22.        
23.     }

But this do not have standart operation handler.

 

AFAIK, AssetReference is a synthetic sugar. Behind the scenes it calls the same kind of Addressables.Instantiate(key), so in theory iterating through the ContentCatalog would be the way to do what you want.

Code (CSharp):

1. var asyncCatalogLoad = Addressables.LoadContentCatalogAsync(catalogPath);
2. while (!asyncCatalogLoad.IsDone)
3. {
4.     yield return new WaitForEndOfFrame();
5. }
6. foreach (var k in asyncCatalogLoad.Result.Keys)
7. {
8.       // your code
9. }

 

Most likely it will not assign Asset field of AssetReferences presented in a list ( AssetReferenceField.LoadAssetAsync<Object>() will assign its Asset variable, and I am looking for similar methods but for collection of asset references).
I have a field which is a List<AssetReference> Assets some there in the script and the content of that list could be changed at runtime. You are referring to some "catalogPath" where do I find that?

 

LoadAssetsAsync ?

 

I have tried Addressable.LoadAssetAsynchroous(assetsAsKeyList, assetAction, mergeAssets) but that did not assign Asset variable of Each AssetReferencesPresented in List (because it is a list of keys).


For example, I have a list of possible assetsReferences as possible itemDefenitions.
Then I randomly generate let say 10 of them a copy them into chest inventory (also list of assetReferences). Now I need to load them all at once and make that so Asset variable of assetReferences in Chest is assigned by whose loaded objects.
Then I need to draw the content of that chest by accessing chests inventory and getting data out of Asset variable of AssetReference ((ItemInChest.Asset as ItemClass).Image/Name so on).

Looks like some function like AddressableAssets.LoadAssetsAsync should be added. I think it is common to load a collection of assets. (not bundle).

 

I meant, this method is already there. It returns a single async op that gives a result of a list of object, so after yield returning the async op then you can access its .Result that contains all objects. I believe you have to use the merge mode Union.

 

I have additionaly tested that function by below code.

Code (CSharp):

1. using System;
2. using System.Collections.Generic;
3. using System.Linq;
4. using UnityEngine;
5. using UnityEngine.AddressableAssets;
6. using Object = UnityEngine.Object;
7.  
8. public class TestSerialise : MonoBehaviour
9. {
10.    
11.     public AssetReference Single;
12.     public List<AssetReference> Multiple;
13.  
14.     public void Start()
15.     {
16.         // Loading AssetReference Directly will asign "Asset" field of Single reference
17.         Single.LoadAssetAsync<Object>().Completed += handle => Debug.Log(Single.Asset);
18.        
19.         // Loading AssetReferences will not assign "Asset" fields
20.         var keys = Multiple.Select(e => e.RuntimeKey).ToList();
21.         var operation = Addressables.LoadAssetsAsync(
22.             keys,
23.             (Action<Object>) Debug.Log,
24.             Addressables.MergeMode.Union);
25.        
26.         operation.Completed += handle =>
27.         {
28.             Debug.Log("COMPLETED");
29.             foreach (var o in Multiple)
30.                 Debug.Log(o.Asset);
31.         };
32.     }
33.  
34.  
35. }
36.  

Example.
I have a list List<AssetReference> ITEMS which may contain same assigned values.
I need to asynchronously load them at ones preferably with AsyncOperationHandle.
Also, it needs either to assign Asset field of each ITEM (ITEMS[x].Asset = LoadedObject)
or perform as many actions as ITEMS.Count.
Because I need to iterate through ITEMS and access each corresponded loaded object.

With Addressables.LoadAssetsAsync I can not match each ITEM and the loadedObject
because if Items contain duplicated assets then this method will return only unique loaded objects.

The solution I provided above loads each ITEM and Assigns ITEM.Asset object field automatically but I do not have benefits of AsyncOperationHandle return type. Then I can iterate through the original list and use corresponded loaded object. (even if that would not happen automatically I could just add objects in the temp object list and return it on completion and it would be the same size so I could match original and loaded lists)

Something like Addressables.LoadAssetsAsync would be usable in that case but only if it would return a list of objects of the same size or perform as much actions.

Is there a way?

 

If you want to iterate per single object you might use Task so result is awaited and you can have control over it.
if you want to use a list of certain assets you might first set the base like relationships and set labels (categories).

In my code I have labels(categories) that represent a list of objects and per each object there is a relationship with certain asset.

the name of the sprite matches the name of the prefab so if I need to load the object I can do it with the name of the sprite following a specific path.

i.e.
Group Models
Models/{category}/prefab(s) . each folder with label model and other label with the specific category.
Group modelicons
Modelicon/{category}/sprite(s) each folder with label modelicons and other label with the specific category.

I hope this can help you as a reference.

Code (CSharp):

1.   List<string> GetActivityCategories3D()
2.     {
3.    
4.         List<string> categories = new List<string>();
5.  
6.         if (categories.Count == 0)
7.             categories.Add("Recycle");
8.  
9.         return categories;
10.     }
11.  
12.     void SetCatsAddressables3d()
13.     {
14.         var activity_cats = GetActivityCategories3D();//get list of allowed cats
15.  
16.         for (int i = 0; i < activity_cats.Count; i++)
17.         {
18.    
19.             var cats = new List<object> { "selectable", "category", $"{activity_cats[i]}" };
20.             int valor = i;
21.             Addressables.LoadAssetsAsync<Texture2D>(cats, null, Addressables.MergeMode.Intersection).Completed += (obj) =>
22.             {
23.                 HandlerCatsLoaded(obj, valor==(activity_cats.Count-1));
24.             };
25.         }
26.        
27.        
28.     }
29.     Cat3dInventory inventory;
30.  
31.     async Task HandlerCatsLoaded(AsyncOperationHandle<IList<Texture2D>> obj, bool isLast)
32.     {
33.         try
34.         {
35.             var catsAllowed = GetActivityCategories3D();//get list of allowed
36.             for (var i = 0; i < obj.Result?.Count; i++)
37.             {
38.                 var sp = Imagine.GetSprite(obj.Result[i]);
39.              
40.                 //filter cats from activity or project
41.                 if (catsAllowed.Contains(sp.name))
42.                 {
43.                     Cat3dInventoryCategory category = new Cat3dInventoryCategory(sp.name, sp);
44.  
45.                     var result = await Addressables.LoadAssetsAsync<Texture2D>(
46.                         new List<object> { "modelicon", sp.name.ToLower() },
47.                         null,
48.                         Addressables.MergeMode.Intersection).Task;
49.  
50.  
51.                     for (int d = 0; d < result?.Count; d++)
52.                     {
53.                         var modelicon = Imagine.GetSprite(result[d]);
54.                         Debug.Log("model icon " + modelicon.name);
55.  
56.                         var prefab = await Addressables.LoadAssetAsync<GameObject>($"Models/{sp.name}/{modelicon.name}.prefab").Task;//load models from modelicons from category
57.                         //iterate over object like prefab.layer = 1
58.  
59.  
60.  
61.                         category.Items.Add(new Cat3dInventoryItem(modelicon.name, modelicon, prefab));
62.                     }
63.                     if(result?.Count>0)
64.                         Addressables.Release(result);
65.  
66.  
67.                     inventory.Categories.Add(category);
68.  
69.                     if (isLast)
70.                     {
71.                  
72.                         BundleLoader._Instance.LoadBundleStreaming("ToolEditor3d", LoadSceneMode.Additive, OnCat3DInitialized);
73.                     }
74.                 }
75.  
76.             }
77.             Addressables.Release(obj.Result);
78.             Cat3DManager.SetInventory(inventory);
79.         }
80.         catch (System.Exception ex)
81.         {
82.             Debug.Log($"couldn't load icon models  {ex.Message}");
83.         }
84.     }