With Xcode 4, what is the proper way have a main project + a shared code project?

Question

Currently I have an iPhone app that is just one large project. It has hundreds of code files. I have one folder called "Helper" that includes all of my classes that I have created. I'm going to be making a second app that also needs to use the exact same code that is in the "Helper" folder.

What is the proper way to share that "Helper" code between two projects/apps? Should I put it in its own project file and then add both the main app + "Helper" to a common workspace? I'm not interested in making static libraries or anything... I just want the code segregated somehow.

I've already tried making a second "blank" project file and dragging the code into it, but when I try to build Xcode just thinks I am missing header files now... for some reason it's not seeing the code in the other project.

Answer 1

It would be ideal if there were a clean distinction between the shared code and the code unique to your current app. If there isn't yet, try to make sure everything that will be shared is not dependent on anything from the code unique to the project.

One way you could accomplish this is by using a Git Repo and then making the shared code its own repo project. Then, in the repo for both projects, include the helper code as a submodule.

I've worked with projects that use submodules, though I haven't set up the submodule aspect myself as of yet. The benefit here is that any changes you make to "helper" can be pulled into the both projects, so the changes are synchronized.

If you aren't familiar with Git yet, I recommend getting familiar. Setting up a Git repo on your computer, even if you aren't collaborating with others, is pretty useful. XCode currently offers the option of setting up a repo when you create your project. If you haven't done that, or aren't sure though, you can still create a repo after the fact.

I use source tree to manage my repositories. Creating a repo is pretty straightforward and easy from there SourceTree. However, you can use GitHub's own desktop client, or any other client if you wish - depending on how you set up your project.

Some information about setting up a submodule in git: Setting up a submodule

So, to recap:

1. Make sure your "helper" code can stand on its own
2. Put the helper code into its own repo
3. Include the helper repo as a submodule to any project you want the code in.

Hope that helps!

Answer 2

It sounds to me the situation you have described is exactly what a framework is designed to solve. What you would likely end up doing is creating another project with all of your shared code within it and creating a framework which your applications could link against.

I would suggest reading Apple's Framework Programming Guide. From the introduction to the guide:

Mac OS X makes extensive use of frameworks to distribute shared code and resources, such as the interfaces to the system itself. You can create frameworks of your own to provide shared code and resources to one or more of your company’s applications. You can also create frameworks containing class libraries or add-on modules with the intention of distributing them to other developers.