Develop Reference

Unity C# interfaces causing "script class cannot be found"

I am using Unity 2019.3.13f1 and Visual Studio Community 2019 version 16.5.4. I have the script InterfaceContainer.cs as follows:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class InterfaceContainer : MonoBehaviour {
// Start is called before the first frame update
void Start() {
}
// Update is called once per frame
void Update() {
}
}
public interface IItem {
public string Name { get; }
public string Path { get; }
public GameObject Icon { get; }
public void Open();
}
Visual Studio gives no compilation errors.
In Unity the inspector of the script says "No MonoBehaviour scripts in the file, or their names do not match the file name." And when I drag the script into a GameObject, it says "Can't add script component "InterfaceContainer" because this script class cannot be found. Make sure that there are no compile errors and that the file name and the class name match."
The names definitely match, because when I deleted the interface part the error didn't exist anymore.
I also tried deleting the class part. It didn't help.
Any subsequent scripts added had the exact same error, whether or not they contain any interfaces, or reference this script.
The weird thing is when I deleted the interface part of this script, refreshed Unity, added this part again, and refreshed Unity again, the error disappears. However all subsequently added scripts still have the same error.
I have no idea what causes this error, and have googled for a long time with no avail. Any help will be greatly appreciated.
EDIT: The error isn't gone when I removed the interface part and added it again; I can still drag the script as a component, when when I try entering playmode it asks me to fix all compiler errors.

Try this:
Right click in the Project Panel of Unity
Import New Asset... and select InterfaceContainer.cs
Try add this script as component again.

One thing I would try is to check if it happens in earlier versions of unity. With the unity hub its easy to have different versions of unity to check this kind of things. Its useful if you are working with one of the latests.
I can confirm that in 2018.4.12, I attach my monobehaviours with interfaces with no problem.
On the other hand you dont implement the Interface you define in your monobehaviour, although that should not be causing any problem, have you tried if implementing the interface in your monobehaviour if you got the error?
Hope that helps

PlayerPrefs working on unity editor but not in build

I've looking for info to try to solve my problem and I just can't figure out what it's causing it. Player Prefs seem to work fine in unity editor, but once i make a build for Android or PC they are all gone. I have PlayerPrefs.deleteAll no where in my project.
I have 3 scenes: Menu, Game and GameOver. When I start the Menu scene, I run this script attached to the MainCamera:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class prefs : MonoBehaviour
{
public static int bestRecord;
// Start is called before the first frame update
void Start()
{
bestRecord = PlayerPrefs.GetInt("K", 1);
Debug.Log(PlayerPrefs.GetInt("K").ToString());
}
}
When I go into the Game scene, my score is a TextMeshProUGUI that is constantly update by an InvokeRepeating:
public TextMeshProUGUI points;
void Start()
{
stop = false;
InvokeRepeating("subirMetros", 0f, 0.01f);
}
private void subirMetros()
{
if (stop == false)
{
points.SetText(Math.Round(character.transform.position.x, 0) + "");
}
}
//GameOver is called when the player dies
public void GameOver()
{
stop = true;
CancelInvoke("subirMetros");
int finalPoints = Int32.Parse(points.text);
int recordActual = PlayerPrefs.GetInt("K");
if (recordActual < finalPoints)
{
PlayerPrefs.SetInt("K", finalPoints);
}
SceneManager.LoadScene("GameOver");
}
}
Finally, when starting the GameOver scene, I get once again the PlayerPrefs that are supposedly saved before I get to the scene:
public TextMeshProUGUI record;
void Start()
{
record.text = PlayerPrefs.GetInt("K").ToString();
}
The weird thing is that this is working in the unity editor, but not when i build it. I would be very grateful if someone could help me, thanks.

I know this is an old post (forgive me for necro) but it came up as a google search result, and i ran into the same issue.
I had the same issue with playerprefs, i was saving an encrypted file where i used a playerprefs together with a generated key for a hash value. When i saved the game in the editor and ran in the build i couldnt load my save file. This was for windows though. After some debugging and digging I found out that unity saves playerprefs two different places for both editor and application builds:
according to this article
https://virtual-reality-piano.medium.com/solved-where-is-unitys-playerprefs-stored-on-windows-d61d504585e9
Your unity editor saves it at the path: ‘HKEY_CURRENT_USER\SOFTWARE\Unity\UnityEditor\CompanyName\ProjectName’
But, when you build your application, the player prefs are saved at:
'HKEY_CURRENT_USER\SOFTWARE\CompanyName\ProjectName' (where Company name is the name of your company, and project name is the name of your project).
I had to go in and delete the registry files in both places, because say i was saving a Save File with the name DefaultPlayer, then the editor would associate that save with the registry file from the editor. But when i build to an application, the save file would still persist in Application.PersistentPath, but it's registry file would not exist, because it wasn't created yet in the application's registry file.
Sorry for the confusing post and necro, but this is what fixed save file problems for me from editor to application builds. (note this is on windows so dont know if it applies to android as well). Hope it helps anyone else running into the same problem
note you would have to delete both files everytime you test in editor and on builds, or as someone suggested in a comment above, use the #if UNITY_EDITOR pragma to avoid the error

I read your post and I have a similar problem with this.
Before I have built an apk file but it was not working on the emulator.
But it was working on Unity Editor well.
I couldn't find the reason for this problem but I think there is a problem when the scene is loading using SceneManager.LoadScene().
When I don't use this function, the error was fixed.
If you fix this problem, please post how did you do.
And I think it is better to avoid errors than fixing errors.
Good luck.

DLL: Library of Images [duplicate]

I cannot get Unity Assetbundles working in an iOS build.
In Unity I build the assetbundles:
using UnityEditor;
public class CreateAssetBundles
{
[MenuItem("Assets/Build AssetBundles")]
static void BuildAllAssetBundles()
{
BuildPipeline.BuildAssetBundles("Assets/AssetBundles", BuildAssetBundleOptions.None, BuildTarget.iOS);
}
}
And they work fine in Unity. using them with
AssetBundle bundleLoadRequest = AssetBundle.LoadFromFile("file://" + Application.dataPath + "/AssetBundles/iOS/" + myassetbundlename.ToString());
and/or
WWW wwww = WWW.LoadFromCacheOrDownload("file://" + Application.dataPath + "/AssetBundles/iOS/" + myassetbundlename.ToString(), 4);
(Without the "file://" prefix, the bundles won't work in Unity nor Xcode)
I build the project to Xcode and run it in Xcode and receive this error:
Unable to open archive file:
/Users/user/Documents/Workspaces/unityproject/Assets/AssetBundles/iOS/lchairanimations
It might be related somehow to setting the correct path, but as I have copied the assetbundle folder afterwards to Xcode project, the problem persists.

In this example below, I will demonstrate how to add new asset called "dog" to our AssetBundle named "animals" and build it then load it during run-time.
Setting Up Build Folders:
1. Select the asset such as image file. In this case, that's the "dog.jpeg" file. See the menu in the "Inspector" tab. Sometimes, the AssetBundle option it is hidden, drag it up to show it. See the animated gif below for how to do this. The default AssetBundle is "None". Click on the "None" option then go to the "New" option and create new AssetBundle and name it "animals"
2. Create a folder named StreamingAssets in the Assets folder. This is the folder we are going to build the AssetBundle into. Spelling counts and it's case sensitive so make sure to name it correctly.
3. Create sub-folder in the StreamingAssets folder to hold the AssetBundle. For this example, name this folder AssetBundles so that you can use it to recognize what's in it.
Building AssetBundle:
4. Below is the build script.
A. Create a script named ExportAssetBundles and put it in a folder named "Editor" in the Assets folder then copy the code below inside it:
using System.IO;
using UnityEditor;
using UnityEngine;
public class ExportAssetBundles
{
[MenuItem("Assets/Build AssetBundle")]
static void ExportResource()
{
string folderName = "AssetBundles";
string filePath = Path.Combine(Application.streamingAssetsPath, folderName);
//Build for Windows platform
BuildPipeline.BuildAssetBundles(filePath, BuildAssetBundleOptions.None, BuildTarget.StandaloneWindows64);
//Uncomment to build for other platforms
//BuildPipeline.BuildAssetBundles(filePath, BuildAssetBundleOptions.None, BuildTarget.iOS);
//BuildPipeline.BuildAssetBundles(filePath, BuildAssetBundleOptions.None, BuildTarget.Android);
//BuildPipeline.BuildAssetBundles(filePath, BuildAssetBundleOptions.None, BuildTarget.WebGL);
//BuildPipeline.BuildAssetBundles(filePath, BuildAssetBundleOptions.None, BuildTarget.StandaloneOSX);
//Refresh the Project folder
AssetDatabase.Refresh();
}
}
B. Build your AssetBudle by going to Assets --> Build AssetBundle menu.
You should see the built AssetBundles inside the Assets/StreamingAssets/AssetBundles directory. If not, refresh the Project tab.
Loading the AssetBundle during run-time:
5. When loading it, Application.streamingAssetsPath should be used to access the StreamingAssets folder. To access all the folders use, Application.streamingAssetsPath + "/AssetBundle/" + assetbunlenameWithoutExtension;. The AssetBundle and AssetBundleRequest API are used to load the AssetBundle. Since this is an image, Texture2D is passed to them. If using a prefab, pass GameObject instead then instantiate it. See comment in code for where these changes should be made. It is recommended to use Path.Combine to combine path names so the code below should use that instead.
Below is a simple loading function:
IEnumerator LoadAsset(string assetBundleName, string objectNameToLoad)
{
string filePath = System.IO.Path.Combine(Application.streamingAssetsPath, "AssetBundles");
filePath = System.IO.Path.Combine(filePath, assetBundleName);
//Load "animals" AssetBundle
var assetBundleCreateRequest = AssetBundle.LoadFromFileAsync(filePath);
yield return assetBundleCreateRequest;
AssetBundle asseBundle = assetBundleCreateRequest.assetBundle;
//Load the "dog" Asset (Use Texture2D since it's a Texture. Use GameObject if prefab)
AssetBundleRequest asset = asseBundle.LoadAssetAsync<Texture2D>(objectNameToLoad);
yield return asset;
//Retrieve the object (Use Texture2D since it's a Texture. Use GameObject if prefab)
Texture2D loadedAsset = asset.asset as Texture2D;
//Do something with the loaded loadedAsset object (Load to RawImage for example)
image.texture = loadedAsset;
}
Things to before loading note:
A. Name of Assetbundle is animals.
B. Name of the asset/object we want to load from the animals Assetbundle is dog This is a simple jpg of a dog.
C. The loading is simple as this:
string nameOfAssetBundle = "animals";
string nameOfObjectToLoad = "dog";
public RawImage image;
void Start()
{
StartCoroutine(LoadAsset(nameOfAssetBundle, nameOfObjectToLoad));
}

I have a suggestion as well that might be more accommodating to developers like me who want something more .Net based. You might consider building a "Launcher" using Unity. I would build it using Unity so it remains cross platform. Next, consider bundling your updates in a DLL since Unity supports .Net framework or store them as a image in a web folder. You can grab your data using Webclient. Article here:
https://learn.microsoft.com/en-us/dotnet/api/system.net.webclient.downloadfile?view=netframework-4.8#System_Net_WebClient_DownloadFile_System_Uri_System_String_
A launcher might be a better way to grab or update your content. I've been toying with the idea every since I played Lord of the Rings Online and I like their Launcher. So I wanted to make one for my own games. In your code you would use "DownloadFile(Uri, String)" to get your data. I would use an API or something to first check your current version of the game or DLL etc. Then check the data base for laest version. Finally the API or something could build a list of new files needed or updated files needed and just loop through requesting the files and download what you need.

Unity "The associated script can not be loaded" and "Win32Exception: The system cannot find the file specified"

so I'm new to Unity and I've been trying to test the scene with the script attatched to a character. However, it keeps saying "The associated script cannot be loaded. Please fix any compile errors and assign a valid script." It also says that the name of the file could be different from the name in the code but it isnt, and also it says that the code could be missing MonoBehaviour Scripts. It wont even allow me to attach the script to characters because it cant find the script class.
I've copied and downloaded character movement codes from the internet but they didnt work either. I've also tried deleting and re-making the CS files but that didnt work either. Even adding empty scripts to characters didnt work unless i do it from "Add component"
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class Movement : MonoBehaviour
{
SpriteRenderer sprite;
Rigidbody2D rigid;
// Start is called before the first frame update
void Start()
{
sprite = GetComponent<SpriteRenderer>();
rigid = GetComponent<Rigidbody2D>();
}
private void FixedUpdate()
{
if (Input.GetKey("d"))
rigid.velocity = new Vector2(2, 0);
else if (Input.GetKey("a"))
rigid.velocity = new Vector2(-2, 0);
}
}
There are also these errors in Unity if that helps

I think your class name is different from file name.

Unity apparently can't handle apostrophes (single-quote ') in the directory name of the editor. You need to get rid of the apostrophe in your directory name. Once you make that change, Unity should be able to build the scripts as intended.
Edit: This has been fixed in more recent versions - see https://issuetracker.unity3d.com/issues/scripts-do-not-get-compiled-if-the-unity-editor-path-contains-apostrophes for reference

First, it is recommended to use "Add component" to create a script, if you want to attach it to a GameObject, as it automatically imports necessary libraries. Implementing MonoBehaviour is necessary for adding a script to a GameObject.
Second, FixedUpdate() should not be set to private, it does not need an access modifier, just like Start(), see https://docs.unity3d.com/ScriptReference/MonoBehaviour.FixedUpdate.html.
Third, the errors in your first screenshot seem to imply that there is a problem with your Unity installation. Try reinstalling it and make sure that the Editor you install matches your operating system (64 or 32 bit?).
Fourth, the second screenshot is shown when you use any obsolete libraries or classes, which does not seem to be the case in the script you shared.
Hope that helps.

It's basically because you deleted some script or renamed it or degraded unity version. you might have to reassign the script at the required position/component.
Note: Make sure that class name is the same as the script name in unity.

Unity asset bundle server automation

I am developing an application in Unity where users can upload their own 3d-models. I have been searching for ways to implement this and the best way to load models from all types seems to be asset bundles. To create these bundles on a server i want to run Unity in batch mode and create the bundles from a static method.
The problem I'm facing is that it seems to be impossible to include objects in a asset bundle from script. In the editor you just select the asset bundle name but to automate this, that won't be possible.

Found the answer using the AssetImporter as i intended in the first place. For some reason I tought I had to instantiate the object in order to bundle it. That was a false assumption and by just adding the project path you can assign a bundlename to a asset.
foreach (string file in filesInFolder)
{
if (!file.Contains(".meta"))
{
AssetImporter importer = AssetImporter.GetAtPath("Assets/models/" + file);
if (importer != null)
{
importer.assetBundleName = BundleName;
Debug.Log("assetBundlesAssigned");
}
else
{
Debug.Log("No asset selected");
complete = false;
}
}
}
When all the assets are assigned you can build them as usual like so.
public static void ExecBuildAssetBundles()
{
Debug.Log("Building bundle");
BuildPipeline.BuildAssetBundles("Assets/AssetBundles", BuildAssetBundleOptions.None, BuildTarget.Android);
}