ModelProject/Assets/Scripts/BundleRequestAsync.cs

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

public class BundleRequestAsync : BundleRequest
{
    private AssetBundleCreateRequest _request;

    public override float progress
    {
        get
        {
            if (isDone)
                return 1;
            if (LoadState == AssetLoadState.Init)
                return 0;
            if (_request == null)
                return 1;
            return _request.progress;
        }
    }

    internal override bool Update()
    {
        if (!base.Update())
            return false;
        if(LoadState == AssetLoadState.LoadAsset)
        {
            if (_request.isDone)
            {
                assetBundle = _request.assetBundle;
                if (assetBundle == null)
                    error = string.Format("unable to load assetBundle:{0}", name);
                LoadState = AssetLoadState.Loaded;
                return false;
            }
        }
        return true;
    }
    internal override void Load()
    {
        if(_request == null)
        {
            _request = AssetBundle.LoadFromFileAsync(name);
            if(_request == null)
            {
                error = name + "LoadFromFile failed.";
                return;
            }
        }
        LoadState = AssetLoadState.LoadAsset;
    }

    internal override void Unload()
    {
        _request = null;
        LoadState = AssetLoadState.Unload;
        base.Unload();
    }

    internal override void LoadImmediate()
    {
        Load();
        assetBundle = _request.assetBundle;
        if (assetBundle != null)
        {
            Debug.LogWarning("LoadImmediate:" + assetBundle.name);
            LoadState = AssetLoadState.Loaded;
        }
    }
}