How to do it...

1. Open your project's .uproject file in a text editor such as Notepad or Notepad++. You can find the file inside your project folder, and it should look similar to what's shown in the following screenshot:

2. Add the bold section of text in the following snippet to the file:

{
  "FileVersion": 3,
  "EngineAssociation": "4.21",
  "Category": "",
  "Description": "",
  "Modules": [
    {
      "Name": "Chapter_10",
      "Type": "Runtime",
      "LoadingPhase": "Default"
    }, 
      { 
          "Name": "Chapter_10Editor", 
          "Type": "Editor", 
          "LoadingPhase": "PostEngineInit", 
          "AdditionalDependencies": [ 
            "Engine", 
            "CoreUObject" 
          ] 
      } 
  ]
}

Note the comma after the first module before the second set of curly braces.

3. In your Source folder, create a new folder using the same name as you specified in your uproject file (in this instance, "Chapter_10Editor"):

4. Open up the Chapter_10Editor.Target.cs file and update it to the following:

using UnrealBuildTool;
using System.Collections.Generic;

public class Chapter_10EditorTarget : TargetRules
{
  public Chapter_10EditorTarget(TargetInfo Target) : base(Target)
  {
    Type = TargetType.Editor;

    ExtraModuleNames.AddRange( new string[] { "Chapter_10Editor" } );
  }
}

5. Inside this new folder, create a blank .txt file and rename it to Chapter_10Editor.Build.cs:

6. Insert the following into the file:

using UnrealBuildTool;

public class Chapter_10Editor : ModuleRules
{
    public Chapter_10Editor(ReadOnlyTargetRules Target) : 
    base(Target)
    {
        PCHUsage = PCHUsageMode.UseExplicitOrSharedPCHs;

        PublicDependencyModuleNames.AddRange(new string[] { "Core", 
        "CoreUObject", "Engine", "InputCore", "RHI", "RenderCore", 
        "ShaderCore", "MainFrame", "AssetTools", "AppFramework", 
        "PropertyEditor"});
    
       PublicDependencyModuleNames.Add("Chapter_10");

        PrivateDependencyModuleNames.AddRange(new string[] { 
        "UnrealEd", "Slate", "SlateCore", "EditorStyle", 
        "GraphEditor", "BlueprintGraph" });

    }
}

7. Still inside of the Chapter10_Editor folder, create a new file called Chapter_10Editor.h and add the following:

#pragma once

#include "Engine.h"
#include "Modules/ModuleInterface.h"
#include "Modules/ModuleManager.h"
#include "UnrealEd.h"
 
 
class FChapter_10EditorModule: public IModuleInterface 
{ 
}; 

8. Lastly, create a new source file called Chapter_10Editor.cpp.
9. Add the following code:

#include "Chapter_10Editor.h" 
#include "Modules/ModuleManager.h"
#include "Modules/ModuleInterface.h"

IMPLEMENT_GAME_MODULE(FChapter_10EditorModule, Chapter_10Editor)

10. Finally, close Visual Studio if you have it open. Then, right-click on the .uproject file and select Generate Visual Studio Project files:

11. You should see a small window launch, display a progress bar, and then close:

12. You can now launch Visual Studio, verify that your new module is visible in the IDE, and compile your project successfully:

13. The module is now ready for the next set of recipes.

Code changes made in this editor module won't support hot-reloading in the same way that code in runtime modules does. If you get a compilation error that mentions changes to generated header files, simply close the editor and rebuild it from within your IDE instead.