Keyboard events Make your custom view deal with keyboard events. Fonts Attributed strings Draw character strings in your custom view. Pasteboard Responder chain Implement copy, cut, and paste. Categories Add a method to an existing class. Drag and Drop Add drag and drop to your custom views.
Timers Create and use timers.
Sheets Attach sheets to your window. Formatters Format a character string and convert it to another type with a custom formatter subclass. Printing Add printing to your application. Deal with pagination. A brief introduction to the text handling system.