JAVA GUI 问题,谢谢各位了.

[ppsau]

import javax.swing.*; // Packages used
import java.awt.*;
public class Converter1 extends JFrame implements ActionListener{
private JLabel prompt = new JLabel("Distance in miles: ");
private JTextField input = new JTextField(6);
private JTextArea display = new JTextArea(10,20);
private JButton convert = new JButton("Convert!");
public Converter1() {
getContentPane().setLayout(new FlowLayout());
getContentPane().add(prompt);
getContentPane().add(input);
getContentPane().add(convert);
getContentPane().add(display);
display.setLineWrap(true);
display.setEditable(false);
convert.addActionListener(this);
} // Converter()

public void actionPerformed( ActionEvent e ) {
double miles = Double.valueOf(input.getText()).doubleValue();
double km = MetricConverter.milesToKm(miles);
display.append(miles + " miles equals " + km + " kilometers\n");
} // actionPerformed()
public static void main(String args[]) {
Converter1 f = new Converter1();
f.setSize(400, 300);
f.setVisible(true);
// Quit the application
f.addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e) {
System.exit(0);
}
} );
} // main()


} // Converter


类MetricConverter我已经写好了,这是个mile转km的问题,上面的程序调不对,请指导.

[wen8876]

import java.awt.event.*

[邵钏]

楼上正解，在我的机器上，将
double km = MetricConverter.milesToKm(miles);
重写为：
double km = miles/1000;
后，该程序可以运行

[rabbit_zizhu]

学习...

[zr_dixuexiongying]

楼上正解
UP