Unity Addressable 预加载方案

发表于 更新于 分类于 Waline：

之前有一篇关于 Unity Addressable 文章介绍了一下它的概念和使用方式，使用它可以将Unity的资源进行拆分，将部分资源放到远程，在需要时再进行加载。

但是如果远程资源比较大的时候，我们可能需要预加载，以及在游戏启动时进行资源的检查和更新。

这篇博客简单记录下如何资源的检查和更新。

首先放上完整的代码

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.AddressableAssets;
using UnityEngine.AddressableAssets.ResourceLocators;
using UnityEngine.ResourceManagement.AsyncOperations;
using UnityEngine.UI;

public class InitEnvironment : MonoBehaviour
{
    private AsyncOperationHandle downloadDependencies;
    private string str;
    private List<object> _updateKeys;

    // Start is called before the first frame update
    void Start()
    {
        _updateKeys = new List<object>();
        UpdateCatalog();
    }

    public async void UpdateCatalog()
    {
        str = "";
        //开始连接服务器检查更新
        await Addressables.InitializeAsync().Task;
        var handle = Addressables.CheckForCatalogUpdates(false);
        await handle.Task;
        Debug.Log("check catalog status " + handle.Status);
        ShowLog("check catalog status " + handle.Status);
        if (handle.Status == AsyncOperationStatus.Succeeded)
        {
            List<string> catalogs = handle.Result;
            if (catalogs != null && catalogs.Count > 0)
            {
                foreach (var catalog in catalogs)
                {
                    Debug.Log("catalog  " + catalog);
                    ShowLog("catalog  " + catalog);
                }
                Debug.Log("download catalog start ");
                str += "download catalog start \n";
                outputText.text = str;
                var updateHandle = Addressables.UpdateCatalogs(catalogs, false);
                await updateHandle.Task;
                foreach (var item in updateHandle.Result)
                {
                    Debug.Log("catalog result " + item.LocatorId);
                    ShowLog("catalog result " + item.LocatorId);
                    foreach (var key in item.Keys)
                    {
                        Debug.Log("catalog key " + key);
                        ShowLog("catalog key " + key);
                    }
                    _updateKeys.AddRange(item.Keys);
                }
                Debug.Log("download catalog finish " + updateHandle.Status);
                ShowLog("download catalog finish " + updateHandle.Status);
                DownLoad();
            }
            else
            {
                Debug.Log("dont need update catalogs");
                ShowLog("dont need update catalogs");
            }
        }
        Addressables.Release(handle);
    }
    /// <summary>
    /// 主界面显示Log
    /// </summary>
    /// <param name="textStr"></param>
    private void ShowLog(string textStr)
    {
        str += textStr + "\n";
        outputText.text = str;
    }

    public IEnumerator DownAssetImpl()
    {
        var downloadsize = Addressables.GetDownloadSizeAsync(_updateKeys);
        yield return downloadsize;
        Debug.Log("start download size :" + downloadsize.Result);
        ShowLog("start download size :" + downloadsize.Result);
        if (downloadsize.Result > 0)
        {
            var download = Addressables.DownloadDependenciesAsync(_updateKeys, Addressables.MergeMode.Union);//, Addressables.MergeMode.Union
            yield return download;
            //await download.Task;
            Debug.Log("download result type " + download.Result.GetType());
            ShowLog("download result type " + download.Result.GetType());
            foreach (var item in download.Result as List<UnityEngine.ResourceManagement.ResourceProviders.IAssetBundleResource>)
            {
                var ab = item.GetAssetBundle();
                Debug.Log("ab name " + ab.name);
                ShowLog("ab name " + ab.name);
                foreach (var name in ab.GetAllAssetNames())
                {
                    Debug.Log("asset name " + name);
                    ShowLog("asset name " + name);
                }
            }
            Addressables.Release(download);
        }
        Addressables.Release(downloadsize);
    }
    /// <summary>
    /// 下载资源
    /// </summary>
    public void DownLoad()
    {
        str = "";
        StartCoroutine(DownAssetImpl());
    }
}

这段代码中有一个需要注意的点，就是如果不先InitializeAsync ,CheckForCatalogUpdates的返回值一定是的Count一定是0，也就是检查不出更新。