Building Cocoa Applications: A Step by Step Guide

Summary

Wow, we’ve really done a lot in this chapter! In the first half of the chapter, we got a taste of multithreaded programming in Mach by creating an application with two execution threads — one that sends data to a back end program and another that reads the resulting values. In the second half, we learned how to draw a picture by building a display list of objects, each of which knows how to draw itself.

In the next chapter, we’ll see how GraphView’s modular design makes it easy to add new functionality to the class. In particular, we’ll see how to add color by subclassing the GraphView class and overriding some of its methods.