Chapter 2 kicks off the book’s example, a simple application to keep track of recipes with their ingredients and perhaps a photo of the completed dish. This chapter gives the first of the three versions of the application, with a very simple data model. The next two versions expand and improve the data model, as is typical of the application development process, which requires versioning and a data migration process, covered in Chapter 5.
I entered the application and it seemed to run, but when I opened it a second time, the recipes I created the previous time were gone. Since the disk file uses an XML format, I was able to read the app’s file in ~/Library/Application Support, and saw that the information I had added was there, it just wasn’t getting loaded in a subsequent run.
I posted a question about this issue on the book’s forum, and then decided to check the nib (.xib) fie. I found that I hadn’t checked the “Prepares Content” box for the Recipes array controller, which tells the controller to load the data from the managed object context when the nib loads. I then promptly answered my own question before anyone else had jumped in. Hopefully nobody got ticked off over the wasted bandwidth.