When you add a folder of files to an Xcode project by choosing File > Add Files to “ProjectName”, you should see the following options at the bottom of the Open panel:
As you can see there are two options for adding folders to a project.
- Create groups
- Create folder references
What’s the difference between creating groups and folder references?
When you create a group for a folder, Xcode creates a gray folder (yellow folder in earlier Xcode versions) for the folder in the project navigator. Create a group when you need to edit the folder’s files in Xcode. If you’re adding a folder of source code files, you should create a group for the folder.
When you create a folder reference, Xcode creates a blue folder in the project navigator. The folder will also be copied to the app bundle when you build the project. Create a folder reference when you don’t need to edit the folder’s files in Xcode. If you’re adding a folder of image or sound files, you should create a folder reference.