One of the differences between programming in Java within the context of the World Wide Web and programming with Java or another language within the context of a conventional computer is the role of input/output. When learning a new language, the first program most people write is a Hello, World! program in which basic I/O capabilities are exercised. When learning to write applets, the Hello, World! equivalent is displaying data on the screen and processing data from the user entered through a user interface component, such as a button or a textfield. Over the next few tutorials, we will develop the knowledge needed to do this.Information to be displayed on the screen must be constructed within some specific context, and, similarly, information received from the user through a screen component is handled within that same context.. Java provides several kinds of contexts. The two that will be discussed here are
PanelsandFrames. Frames are separate windows whereas panels are areas contained within a window. Thus, most applets that run within a WWW browser are written as panels.
Topics
Begin discussion of Java AWT Contexts.
- Panels
- Frames
References
Useful references include:
- Introduction to O-O Programming in Java class tutorial
- Java Overview
- Sun's Java Development Kit (JDK)
- The API
- The API Class Hierarchy
- Source Code for JDK Packages
Assignment for Next Class
- Read the Java Events I.