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can probably give you what you want if you’re willing to do the research by hunting through the online documentation from Sun.
Benefits of Swing
When you begin to use the Swing library, you’ll see that it’s a huge step forward. Swing components are Beans (and thus use the Java 1.1 event model), so they can be used in any development environment that supports Beans. Swing provides a full set of UI components.
For speed, all the components are lightweight (no “peer” components are used), and Swing is written entirely in Java for portability.
Much of what you’ll like about Swing could be called “orthogonality of use;” that is, once you pick up the general ideas about the library you can apply them everywhere. Primarily because of the Beans naming conventions, much of the time I was writing these examples I could guess at the method names and get it right the first time, without looking anything up. This is certainly the hallmark of a good library design. In addition, you can generally plug components into other components and things will work correctly.
Keyboard navigation is automatic – you can use a Swing application without the mouse, but you don’t have to do any extra programming (the old AWT required some ugly code to achieve keyboard navigation). Scrolling support is effortless – you simply wrap your component in a JScrollPane as you add it to your form. Other features such as tool tips typically require a single line of code to implement.
Swing also supports something called “pluggable look and feel,” which means that the appearance of the UI can be dynamically changed to suit the expectations of users working under different platforms and operating systems. It’s even possible to invent your own look and feel.
Easy conversion
If you’ve struggled long and hard to build your UI using Java 1.1, you don’t want to throw it away to convert to Swing. Fortunately, the library is designed to allow easy conversion –
in many cases you can simply put a ‘J’ in front of the class names of each of your old AWT
components. Here’s an example that should have a familiar flavor to it:
//: JButtonDemo.java
// Looks like Java 1.1 but with J's added
package c13.swing;
import java.awt.*;
import java.awt.event.*;
import java.applet.*;
import com.sun.java.swing.*;
public class JButtonDemo extends Applet {
JButton
b1 = new JButton("JButton 1"),
b2 = new JButton("JButton 2");
JTextField t = new JTextField(20);
public void init() {
ActionListener al = new ActionListener() {
public void actionPerformed(ActionEvent e){
String name =
Chapter 13: Creating Windows & Applets
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((JButton)e.getSource()).getText();
t.setText(name + " Pressed");
}
};
b1.addActionListener(al);
add(b1);
b2.addActionListener(al);
add(b2);
add(t);
}
public static void main(String args[]) {
JButtonDemo applet = new JButtonDemo();
JFrame frame = new JFrame("TextAreaNew");
frame.addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e){
System.exit(0);
}
});
frame.getContentPane().add(
applet, BorderLayout.CENTER);
frame.setSize(300,100);
applet.init();
applet.start();
frame.setVisible(true);
}
} ///:~
There’s a new import statement, but everything else looks like the Java 1.1 AWT with the addition of some J’s. Also, you don’t just add( ) something to a Swing JFrame, but you must get the “content pane” first, as seen above. But you can easily get many of the benefits of Swing with a simple conversion.
Because of the package statement, you’ll have to invoke this program by saying: java c13.swing.JbuttonDemo
All of the programs in this section will require a similar form to run them.
A display framework
Although the programs that are both applets and applications can be valuable, if used everywhere they become distracting and waste paper. Instead, a display framework will be used for the Swing examples in the rest of this section:
//: Show.java
// Tool for displaying Swing demos
package c13.swing;
import java.awt.*;
import java.awt.event.*;
import com.sun.java.swing.*;
public class Show {
public static void
inFrame(JPanel jp, int width, int height) {
576
Thinking in Java
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String title = jp.getClass().toString();
// Remove the word "class":
if(title.indexOf("class") != -1)
title = title.substring(6);
JFrame frame = new JFrame(title);
frame.addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e){
System.exit(0);
}
});
frame.getContentPane().add(
jp, BorderLayout.CENTER);
frame.setSize(width, height);
frame.setVisible(true);
}
} ///:~