How to make inventory system for mobile game

Hi guys so I currently make an inventory system from this tutorial. He is using json (LitJSON) in his inventory system. It worked well on pc, and then I tried it for mobile game but unluckily it didn't work. The item doesn't show in the slots. But I think we can use json on android.
Anyone know why his inventory system didn't work on android ? Or maybe you guys have any recommendation to make an inventory system for android ? Thanks.

 

do ScriptableObjects work on mobile?

 

hmm.. I don't think ScriptableObjects can be used for in game save purpose. From what I know ScriptableObject is for Editor only

 

Yes, scriptableobjects work on mobile. No, they are not editor only. No, they aren't to be used for saving (directly). JSON works on everything.

What doesn't work? Have you profiled it? Are there errors? Gonna need some more details to provide any usable advice.

 

I don't have any errors on my script. The items didn't show up on slots in mobile but it shows up in pc version. In his tutorial, the tutor create the json file in a folder named StreamingAssets and that folder placed under Assets folder. And when I build it for pc, there is a folder also named StreamingAssets that has a json file on it.
I don't have any experience in using json for mobile, but I'm guessing that maybe for mobile we need to create a json file via script and place it using

Code (CSharp):

1. Application.persistentDataPath

. Am I guessing right ?
If so how do I create a json file via script ?

 

Streaming assets are handled differently for different platforms:
https://docs.unity3d.com/Manual/StreamingAssets.html

But as long as you use Application.streamingAssetsPath, it will point to the right location.
If you are not seeing errors, you should add some debugging to your application, to help you find out what is going on. It can help you find out exactly where things are going wrong, like is the file loading, is it parsing, is it parsing the way you expect. Profiling it will help isolate the problem.

 

To be honest I just knew that StreamingAssets is a special folder from Unity. I thought that's just a normal folder.
So if I placed json file under that folder, I can access it using Application.streamingAssetsPath ? I will give it a try now.

I'm sorry I'm afraid that I don't know how to debug it on mobile.

 

So I've tried to get the json file in StreamingAssets folder using Application.streamingAssetsPath. It worked on the Editor but it still didn't work on android. I have no clue what's cause this problem.

 

Add some debug.log s around your methods that are doing the loading and check to see if it is loaded and what the content is.

Attach the debugger to see what it is outputting.
Here's how to debug on device:
https://docs.unity3d.com/Manual/AttachingMonoDevelopDebuggerToAnAndroidDevice.html

 

I have tried so many times to attach the debugger by following the instruction you give to me but I still can't connect my device with adb until know. No luck at all.

 

I come back sir. So I have checked if the json file is exist or not in StreamingAssets folder and show it using Text UI. And the result is false. There are 2 probabilities, the file is moved to another directory or the file is destroyed when it was installed.
And then I found this guy faced similar problem with json and solved it. But I tried his solution and still failed.

 

Code (CSharp):

1. using UnityEngine;
2. using System.Collections;
3. using LitJson;
4. using System.Collections.Generic;
5. using System.IO;
6.  
7. public class ItemDatabase : MonoBehaviour {
8.  
9.     private List<Item> _database = new List<Item>();
10.     private JsonData _itemData;
11.  
12.     void Start() {
13.         Debug.Log(Application.streamingAssetsPath);
14.         if(Application.isMobilePlatform){
15.             StartCoroutine("Mobile");
16.         }
17.         else if(Application.isEditor){
18.             if(File.Exists(Application.streamingAssetsPath + "/Items.json")){
19.                 Debug.Log("Exists");
20.             }
21.             _itemData = JsonMapper.ToObject(File.ReadAllText(Application.streamingAssetsPath + "/Items.json"));
22.         }
23.         ConstructItemDatabase();
24.     }
25.  
26.     IEnumerator Mobile() {
27.         WWW loadDb = new WWW(Application.streamingAssetsPath + "/Items.json");
28.         while(!loadDb.isDone){
29.             yield return loadDb;
30.             File.WriteAllBytes(Application.persistentDataPath + "/Items.json", loadDb.bytes);
31.         }
32.         _itemData = JsonMapper.ToObject(File.ReadAllText(Application.persistentDataPath + "/Items.json"));
33.     }
34.  
35.     public Item FetchItemByID(int id) {
36.         for(int i = 0; i < _database.Count; i++){
37.             if(_database[i].ID == id){
38.                 return _database[i];
39.             }
40.         }
41.         return null;
42.     }
43.  
44.     void ConstructItemDatabase() {
45.         for(int i = 0; i < _itemData.Count; i++){
46.             _database.Add(new Item(
47.                 (int)_itemData[i]["id"], _itemData[i]["title"].ToString(),
48.                 (int)_itemData[i]["value"], _itemData[i]["description"].ToString(),
49.                 (bool)_itemData[i]["stackable"], _itemData[i]["slug"].ToString()));
50.         }
51.     }
52. }
53.  
54. public class Item {
55.  
56.     public int ID { get; set; }
57.     public string Title { get; set; }
58.     public int Value { get; set; }
59.     public string Description { get; set; }
60.     public bool Stackable { get; set; }
61.     public string Slug { get; set; }
62.  
63.     public Item(int id, string title, int value, string description, bool stackable, string slug) {
64.         this.ID = id;
65.         this.Title = title;
66.         this.Value = value;
67.         this.Description = description;
68.         this.Stackable = stackable;
69.         this.Slug = slug;
70.     }
71.  
72.     public Item() {
73.         this.ID = -1;
74.     }
75. }

By the way this is the script that I used to communicate with json file.