Java Swing - Lecture 1 An Introduction Milena Radenkovic ([email protected])@cs.nott.ac.uk slides...

Java Swing - Lecture 1An Introduction

Milena Radenkovic([email protected])

slides originally by Chris Coleman

G5BUID - Java Swing - 2007

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

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

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

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

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

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

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

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


• Computer Science Department Stuff… PCs

Java 2 (1.5.0) on hard disk at \cs\java

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


• 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

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

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

A typical Swing program

• Consists of multiple parts Containers Components Events Graphics (Threads)

• Now look at each in turn


15

A simple Swing program - Containers

• Containers


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

A simple Swing program - Components

• Components


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

A simple Swing program - Events

• Events


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

A simple Swing program - Graphics

• Graphics

• Complex drawing andshading API.

• Can do far more than display images.


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

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

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

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

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

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

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

Java Swing - Lecture 1 An Introduction Milena Radenkovic ([email protected])@cs.nott.ac.uk slides...

Documents

Transcript of Java Swing - Lecture 1 An Introduction Milena Radenkovic ([email protected])@cs.nott.ac.uk slides...