Why is Xcode not prefixing filenames?
xcode
Solution
You have to add it manually. When you create a new project just fill out the "Class Prefix" field on the screen where you name the project/bundle id/ etc..
Just add your prefix where I wrote "THIS IS THE PREFIX" in the screenshot below
If you want to add a prefix after you've created your project, you can do so in the file inspector on Xcode's right pane:
Problem
When I start an iOS single view application project, the AppDelegate files and ViewController files are not prefixing with the project name like they used to. files names are as follows when I open a new project: AppDelegate.h AppDelegate.m MainStoryBoard.storyboard ViewController.h ViewController.m Why is this?