Now we are ready to move onto the programming. The first thing we need to allow the user to do is to take a new picture. In order to do that, we are going to need some code to run every time the user taps on the add button. We achieve this by connecting the trigger action of the add button to a method on our view controller. Normally we make a connection by right-click dragging from the button to the code; however, we can't do this if we can't see the interface and the code at the same time. The easiest way to do this is to show the Assistant Editor. You can do this by navigating to View | Assistant Editor | Show Assistant Editor. Also, make sure it is configured to be automatic by clicking on the bar at the top of the editor:
This mode causes the second view to automatically change to the most appropriate file according to what you have selected on the left. In this case, because we are working with the interface of our view controller, it shows the code for the view...