This document provides an introduction to Java Swing. It outlines the timeline for lectures on Swing topics. It emphasizes that a strong understanding of core Java concepts is required before learning Swing. It describes Swing as the Java Foundation Classes toolkit for building graphical user interfaces and distinguishes it from AWT. Finally, it previews that tomorrow's lecture will cover Swing components and containers in more detail.

1. Java Swing - Lecture 1
An Introduction
Milena Radenkovic
(mvr@cs.nott.ac.uk)
slides originally by Chris Coleman

2. 2
Timeline
• 26th
Oct (Now) - Java Necessaries, Swing Basics
• 27th
Oct - Components and Containers
• 3rd
Oct - Layout Management
• 9th
Nov - Event Handling and Listeners
• 10th
Nov - Graphics with Swing
• Java Labs TBA

3. 3
Before we Start… (1)
• Swing is all Java.
• You must know about, and understand:
 Classes / Objects
 Method Overloading
 Inheritance
 Polymorphism
 Interfaces
 How to read the Java2 API Documents

4. 4
Before We Start… (2)
• If Java is a problem – learn NOW, not later
when the coursework is due!
 Labs
 Come to the labs and help is there for both Java and
Swing.
 Web
 Use the Sun/Java tutorials
 Plenty of web resources out there, even the PRG notes
 Read a book?

5. 5
2D interface programming
toolkits
• Tcl/Tk
• Motif/UIL
• IDEs (e.g. VB, MSVC++/MFC)
• Java AWT – the beginnings
• Java JFC Swing (Java2 - JDK >= 1.2)
• JBuilder and other Java IDEs
• etc…

6. 6
What is Swing?
• A part of The Java Foundation Classes
 Swing
 Look and feel
 Accessibility
 Java 2D (Java 2 onwards)
 Drag and Drop
 etc
• Can be used to build Standalone Apps as well
as Servlets and Applets

7. 7
On-line reading and reference
• The Java Swing trail:
http://java.sun.com/docs/books/tutorial/uiswing/
• Swing articles:
http://java.sun.com/javase/technologies/desktop/articles.jsp
• Developer Technical Articles & Tips:
http://java.sun.com/developer/technicalArticles/GUI/

8. 8
Books
• Java Swing (1998), Robert Eckstein,
Mark Loy, Dave Wood, O'Reilly
• JFC Swing Tutorial, The: A Guide
to Constructing GUIs, 2nd Edition
(2004); K. Walrath and M. Campione,
Addison Wesley

9. 9
Getting started with Swing (1)
• Compiling & running programs
 Swing is standard in Java 2 (JDK >= 1.2)
 Use:
 ‘javac <program.java>’ && ‘java <program>’
 Or JCreator / IDE

10. 10
Getting started with Swing (2)
• Computer Science Department Stuff…
 PCs
 Java 2 (1.5.0) on hard disk at csjava
 Unix (tuck and much):
 Java 2 (1.5.0) in /usr/bin (or /usr/java)
 Differences between previous versions
 http://java.sun.com/j2se/1.4.2/docs/guide/swing/SwingChanges.html
 http://java.sun.com/j2se/1.5.0/docs/guide/swing/SwingChanges.html
 Coursework marked on Win XP & JDK
1.5.0

11. 11
Getting started with Swing (3)
• Swing, like the rest of the Java API is
subdivided into packages:
 javax.swing, javax.accessibility,
javax.swing.border …
• At the start of your code - always
 import javax.swing;
 import javax.swing.event;
• Most Swing programs also need
 import java.awt.*;
 import java.awt.event.*;

12. 12
Differences between Swing and
AWT (1)
• Never mix Swing and AWT components
• If you know AWT, put ‘J’ in front of
everything
 AWT: Button
 Swing: JButton
• Swing does all that AWT does, but better
and there’s much more of it.

13. 13
Differences between Swing and
AWT (2)
• Buttons and labels can display images
• Behaviour and appearance of components
• Component shape
• Borders
• Assistive technologies
• Look and feel of the program’s GUI
 Windows – (but only on Windows, M$ issues….)
 UNIX
 GTK
 etc

14. 14
A typical Swing program
• Consists of multiple parts
 Containers
 Components
 Events
 Graphics
 (Threads)
• Now look at each in turn

15. 15
A simple Swing program -
Containers
• Containers

16. 16
Remember this about
Containers:
• The structure of containers is your design
decision and should always be thought
through in advance
 particularly for managing components
 nesting containers
• Failure to do so usually either results in a
messy interface, messy code or both.

17. 17
A simple Swing program -
Components
• Components

18. 18
Remember this about
Components:
• There are many components that make your job
much easier.
• Often, you will be able to customise an existing
Swing component to do a job for you, instead of
having to start from scratch
 Eg can extend (inherit from) the JButton class and
‘paint’ a new button over the top

19. 19
A simple Swing program -
Events
• Events

20. 20
Remember this about events:
• ‘Events’ as seen by GUIs do not happen
all that often in an application
• Consider what is happening between events
as well as during them

21. 21
A simple Swing program -
Graphics
• Graphics
• Complex drawing and
shading API.
• Can do far more than
display images.

22. 22
Remember this about
Graphics:
• There are many aspects of Swing that
allow you to achieve graphics-like things
without actually using ‘Graphics’.
• Therefore, you don’t have to use them
most of the time, and it is often easier not
to.

23. 23
A simple Swing program -
Threads
• Most simple Swing GUI applications don’t
require use of any (extra) threads
• As Swing creates event-driven programs,
all code is executed on the event-
dispatching thread

24. 24
Remember this about Threads:
The single-thread rule
“Once a Swing component has been realized,
all code that might affect or depend on the
state of that component should be executed in
the event-dispatching thread”
(with some exceptions)

25. 25
How to Learn Swing
• Don’t even try.
• Learn general framework principles and
design styles.
• Then use the API reference, and Swing
Tutorials to discover detailed usage of
each component.

26. 26
How to read Java Docs (1)
• Java 2 (J2SE 1.5.0) API Reference:
 http://java.sun.com/j2se/1.5.0/docs/api/
• Split into 3 Sections (html frames):
 Top Left: Packages
 Bottom Left: Classes in Packages
 Main Frame: Information about selected Class

27. 27
How to read Java Docs (2)
• General idea is find class, and examine main
frame for information.
• Main frame pages split into sections:
 Package hierarchy & implemented interfaces
 Class Description, and links to more info
 Nested Class Summary – Detail in separate page
 Fields - 2 types Class (static) and instance, plus fields
inherited from parent classes / interfaces
 Constructor Summary
 Method Summary & inherited methods from parents
 Detailed info on all summary sections

28. 28
Summary
• Do you know enough Java?
• 2D interface programming toolkits
• JFC/Swing
• AWT and Swing
• Getting started with Swing
• Parts of a simple Swing program
• Tomorrow: Components and Containers
• Some source code, and design styles