iOS Components and Frameworks: Understanding the Advanced Features of the iOS SDK

Interacting with UIDocument

To create a new instance of a UIDocument subclass, first determine the URL where the file needs to be saved. When the user taps the plus button in the sample app, the master view controller has a method to determine a filename for a new note called newMyNoteName. That method starts with “MyNote” as a base, and adds a number at the end. It checks for the existence of a note with that filename, and then increments the number if one already exists, until an unused filename is created. That filename is added to the end of the iCloud directory URL path to get the full path for the file. That URL is then passed to the detail view controller, where the configureView method determines whether the file already exists using ...