Chapter 6
Applets, HTML, and GUI's
JAVA IS A PROGRAMMING LANGUAGE DESIGNED for
networked computers and the World Wide Web. Java applets
are downloaded over a network to appear on a Web page. Part of
learning Java is learning to program applets and other Graphical
User Interface programs. GUI programs are event-driven.
That is, user actions such as clicking on a button or pressing a key on
the keyboard generate events, and the program must respond to these events
as they occur.
Event-driven programming builds on all the skills you have learned in
the first five chapters of this text. You need to be able to write the subroutines that
respond to events. Inside these subroutines, you are doing the kind
of programming-in-the-small that was covered in Chapters 2 and 3. And
of course, objects are everywhere. Events are objects. Applets
and other GUI components are objects. Events are handled by instance methods
contained in objects. In Java, event-oriented programming is object-oriented
programming.
This chapter covers the basics of applets, graphics, components,
and events. There is also a section that covers
HyperText Markup Language (HTML), the language used for writing Web pages.
The discussion of applets and GUI's will
continue in the next chapter with more details and with more
advanced techniques.
Contents Chapter 6: