Unity - Can't add script behaviour CallbackExecutor [duplicate] - unity3d

Yesterday I updated unity from unity5 to 2018.2.2f1. Unity scripts are not loading after Update 2018.2.2f1.
Once I try to play the Scene the scripts are not loaded and I can't add the script again it gives this error:
Can't add script component 'CubeScript' because the script class
cannot be found. Make sure that there are no compile errors and that
the file name and class name match.

If you still have the old copy of the project, upgrade the Unity project to Unity 2017 first then to 2018.2.2f1.
Here are the few possible reasons you may get this error(Ordered from very likely)
1.Script name does not match class name.
If script name is called MyClass, the class name must be MyClass. This is also case-sensitive. Double check to make sure that this is not the issue. To make sure that's not the issue, copy the class name and paste it as the script name to make sure that this is not the issue.
Note that if you have have multiple classes in one script, the class name that should match with the script name is the class that derives from MonoBehaviour.
2.There is an error in your script. Since this is an upgrade, there is a chance you're using an API that is now deprecated and removed. Open your script with Visual Studio and see if there is an error there then fix it. There is usually a red line under a code that indicates there is an error.
3.Bad import with the Unity importer and its automatic upgrade script.
Things to try:
A.The first thing to do is restart the Unity Editor.
B.Right click on the Project Tab then click "Reimport All"
C.If there is still issue, the only left is deleting the problematic script and creating a new one. There is an easier way to do this if the script is attached to many GameObjects in your scene.
A.Open the script, copy its content into notepad.
B.From the Editor and on the Project tab right click on the script "CubeScript", select "Find References In Scene".
C.Unity will now only show all the GameObjects that has this script attached to them. Delete the old script. Create a new one then copy the content from the notepad to this new script. Now, you can just drag the new script to all the filtered GameObject in the scene. Do this for every script effected. This is a manual work but should fix your issues when completed.

Here, is some reason why that's heaping.
1. Your Script Name And your class name isn't same.
2. May be there is an error in your script.
Here, is the few way to resolve it.
1. Make a same name of script and class in to this script.
2. find there is the error? and try to resolve it.

Posting here for historic purposes and if someone from Google ends up here, I strictly had the same problem (I'm on Windows 10) and here's how I fixed it :
If you click on the Console, you should see a blank error. Don't worry, it's a Editor bug, and you can see the Editor Log by selecting the console's window dropdown and selecting Open Editor Log.
For me, the problem was that "Tools\Roslyn\csc" could not be found, something that Unity uses to compile C# files.
I opened C:\Program Files\Unity\Hub\Editor\2019.2.14f1\Editor\Data\Tools\RoslynScripts\unity_csc.bat and I added ".exe" to the line "%APPLICATION_CONTENTS%\Tools\Roslyn\csc" /shared %*
(This line should now be : "%APPLICATION_CONTENTS%\Tools\Roslyn\csc.exe" /shared %*)
Now it works perfectly.

I'm completely new to Unity and game development, but I found that making the error true by entering an incorrect name, then entering the right one seems to "trick" Unity into fixing its error.

I had the same error show up but for different reasons (in case someone ends up here from google).
I was a beginner and named my file with a space in it. I got the same error after that. Make sure to NOT include spaces in your C# script.

One more thing which might help apart from other answers
Make the class which inherits from the MonoBehaviour the first class in the file. It fixed this issue for me.

Checking the console bugs and fix them is a good way to solve the problems "Can't add script component because the script class cannot be found?", although the bug seems to be irrelevant.
This works for me when I fix a bug in the other script.

for me I found out it was a script that I wasn't using which was linked to the player and other scripts that I deleted.

For me, the problem was that there was an error in another script.
Once I fixed the error, I could FINALLY attach my other scripts onto my gameobjects.

I just had this issue where I had a perfect script, no errors, and the same name as it should be but no matter what it wouldn't let me add it to a gameObject.
There was another script that was completely unrelated but it had an error in that and somehow that prevented me from adding my good new script.

Like some folks already posted here - the issue might be of a different code.
I was trying to add a script that was referenced by another one which had errors - it doesn't tell you that is the reason, although visual studio kinda suggests it by showing you the errors in the open script.
Just delete the bigger (errored) script and start adding to the unity project from the basic ones.

I had this issue where I had a good script, no errors, good name, restarting unity, following a tutorial exactly but still had this issue.
The way I fixed this is just deleting this buggy script file and creating it again. It fixed my problem perfectly! Now I could add the script to my game object with no such errors!
Hope this helps you! Cheers!

Related

Issue with errors in Unity on launch

I am having an issue in Unity where every time I launch the editor it asks me to enter in safe mode because there are a lot of errors and when I press ignore it launches and I can see in the console a lot of errors with the UI and I found out that I cant create UI elements directly in the hierarchy. I tried to update from 2020.3.13f1 to 2020.3.14f1 and for the first launch everything was fine, with no errors, and I could create UI elements but then when I restarted to make sure everything was actually fine, all the errors popped up again and I cant create UI. Why does this happen and does anyone have a fix because I can't find it anywhere online.
Try not to enter Safe Mode. Enter the editable project. There go to Assets-Reimport All.
It did it to me too, it's probably a Unity bug, this method fixes it. Practically it reimports the whole project by itself, avoiding that the bug gives you problems (such as those like UnityEngine.UI does not exist or Monobehavior does not exist, etc.)
Obviously you will not lose any assets and everything will be fine as before receiving the errors.
Have this issue with any template 2020+ versions
Always shows 2 empty errors on console at first run ,even on an empty project
Will try to install 2019 and hopefully work again
in my case some side app ran caused some error in the installation of Unity.
Nothing amid aboves helped.
Thus I decided to fully reinstall it from scratch to default one.
Now it worksok. But before that . To wipe out the Unity thorowly you need in:
uninstalling Unity and UnityHub in windows' settings
remove all related/remained folders in "C:\Program Files"
remove related/remained folders in "C:\Users\myname\AppData\Local "
in Register Editor go to clean unity like folders in "Computer\HKEY_CURRENT_USER\SOFTWARE"
optionally, remove sample projects in "C:\Users\myname"
You're very likely simply opening the wrong folder, it's a common mistake
Or, you have possibly moved around the folders that you cannot move
Also - it's a nuisance but it's best to install the "hub"

Cucumber-eclipse-maven- project

I have a question and I have been looking for a lot of reviews and nothing seems to work.
I am trying to run my project in my mac.
And always than I put in my cucumber file for example:
example:
only the line where I use "<>" show the next message : "step does not have a matching glue code.
and I totally sure that the same name is connected with his method in my page objects.
The weird thing is that in my windows computer the project run perfectly. I don't know why occurs this.
I hope you can help me.

error cs2001 source file could not be found 2018

Ever since i open my project in unity today every script existed/Created have been given me
Error cs2001 source file "ScriptName.Cs" could not be found
I have reinstalled Unity, Tried Updating it and even created a new project. Still same outcome.
Ever time i tried attached my scripts to a object, it's have given me the error
Can't add script behaviour VisualContainerAsset",Can't Add Script "The script needs to derive from MonoBehaviour!"
Here is some pics how it's looks after i create a C# Script.
Sorry if i sound a bit confused!
UPDATE!:
Malware Bytes was the problem, it would't allow mono developed.
Could you show me one of the scripts? Maybe it misses some of the imports (using UnityEngine;) at the top. Or maybe they don't inherit from MonoBehaviour (classname: MonoBehaviour). It's strange nonetheless...

Unity built-in Packages Compiler Errors

I just started learning how to use Unity to make a simple 3D game.
It's working fine when it comes to creating the environment, but once I imported the built-in Character package it gave me a compiler error and wouldn't run (All compiler errors have to be fixed before you can enter playmode!).
Removing the imported package removes the error and it can run, I tried using other built-in packages like 2D or Cameras but same problem occurred.
After adding 2D package, here's the console (error with no text):
After adding a character from the package, here's what the Inspector says (the associated script cannot be loaded. please fix all compiler errors and assign a valid script):
As shown in the pictures I'm using unity 5.6.0f3 64-bit.
I tried uninstalling and re-downloading it again but that didn't work.
I tried creating a new empty project, import a package and hit run, still didn't work.
A working solution from this post.
Hi, I reported this as a bug and I just got the response from Unity today. Try changing system locale to not Arabic. Go to Control Panel > Change date, time or number format> Administrative tab> Change system locale
Check if the script file name is the same as the class name in the file? They should be the same.
UPDATE
See this part of the picture.
No Monobehaviour scripts in the file, or the names do not match the file name.
And from here,
MonoBehaviours inside namespaces break, if they have a method with a default parameter (such as public void Foo(bool bar=true)).
See also here.
And it seems an identical issue of Compile Error with empty message.
Solution from the post:
Could get a Error message on another computer and it's the same as
mentioned in this Thread:
Creating managed DLL for Unity fails with error when importing into Unity
Which lead to this:
http://forum.unity3d.com/threads/5-2-1p3-mono-cecil-assemblyresolutionexception-unityengine-ui-dll.361666/
I could actually solve it with manually deleting all remains of Unity
and Monodevelop after the deinstallation (ex.
C:\Users[YourUserName]\AppData\Local etc. ) and then reinstalling
5.2.3f.

Groovy debugger out of sync

I am having a difficulty while attempting to debug some code in grails. It is difficult to put into text, so I have posted a screencast showing exactly what the problem is here. In short, while I am debugging the debugger starts jumping from place to place and not following the program logic I have in place. The only other similar question I have found is a year old, had no solution, and can be found here.
The best guess I have so far is that the debugger is displaying the text I have typed in, but is actually executing an older version of the class file which it has cached somewhere. Therefore, I tried:
cleaning the project
manually deleting all of the class files from the target folder and from the target-eclipse folder
Searching my entire hdd for additional files with similar names
removing my project from the workspace and re-adding it
closing and reopening the IDE
grails refresh-dependencies
Importing the project into a new IDE (I was using GGTS, I switched to IntelliJ)
None of those solutions had any effect. I realized that the issue was in a .groovy file, and I was writing almost pure Java, so I deleted the .groovy file, and re-created the class in a .java file. That solved my problem. Unfortunately I am having the problem again, and this time it is in a controller that heavily relies on the grails framework, so that solution is not an option. Other than also being in a .groovy file, another similarity is that the code breaks on an if statement.
My next steps:
Verify that the application is not executing the code I see by using print functions to monitor actual execution flow.
comment out the entire function and re-add functionality one line at a time to see if I can see what breaks it.
Delete the .groovy file, and re-create it as another .groovy file.
Any help is appreciated, and since I can't find any answers online I will continue to update this question as I learn more.
See my comment on the jira issue that you raised. You have found a problem with the groovy compiler and how it calculates line numbers. This is not a problem with executing the wrong class files or using a broken debugger. The debugger is doing exactly what it is expected to do. It is the compiler that is providing erroneous line number information.
The next step, as described in the issue, is to provide a simple project that recreates the bug. I tried to do so myself, but could not. So, please supply something that we can work with. Then we can notify the groovy compiler team.