import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.accessibility.*;
public class HelloSwing implements ActionListener {
private JFrame jFrame;
private JLabel jLabel;
private JPanel jPanel;
private JButton jButton;
private AccessibleContext accContext;
private String labelPrefix = "Number of button clicks: ";
private int numClicks = 0;
public void go() {
jFrame = new JFrame("HelloSwing");
jLabel = new JLabel(labelPrefix + "0");
jButton = new JButton("I am a Swing button!");
jButton.setMnemonic('i');
jButton.addActionListener(this);
accContext = jButton.getAccessibleContext();
accContext.setAccessibleDescription("Pressing this button increments " +
"the number of button clicks");
jPanel = new JPanel();
jPanel.setBorder(BorderFactory.createEmptyBorder(12.30,30,10,30));
jPanel.add(jButton);
jPanel.add(jLabel);
jFrame.setContentPane(jPanel);
WindowListener wl = new WindowAdapter() {
public void windowClosing(WindowEvent e) {
System.exit(0);
}
};
jFrame.addWindowListener(wl);
jFrame.pack();
jFrame.setVisible(true);
}
// Button handling.
public void actionPerformed(ActionEvent e) {
numClicks++;
jLabel.setText(labelPrefix + numClicks);
}
public static void main(String[] args) {
HelloSwing helloSwing = new HelloSwing();
helloSwing.go();
}
}
import java.awt.event.*;
import javax.swing.*;
import javax.accessibility.*;
public class HelloSwing implements ActionListener {
private JFrame jFrame;
private JLabel jLabel;
private JPanel jPanel;
private JButton jButton;
private AccessibleContext accContext;
private String labelPrefix = "Number of button clicks: ";
private int numClicks = 0;
public void go() {
jFrame = new JFrame("HelloSwing");
jLabel = new JLabel(labelPrefix + "0");
jButton = new JButton("I am a Swing button!");
jButton.setMnemonic('i');
jButton.addActionListener(this);
accContext = jButton.getAccessibleContext();
accContext.setAccessibleDescription("Pressing this button increments " +
"the number of button clicks");
jPanel = new JPanel();
jPanel.setBorder(BorderFactory.createEmptyBorder(12.30,30,10,30));
jPanel.add(jButton);
jPanel.add(jLabel);
jFrame.setContentPane(jPanel);
WindowListener wl = new WindowAdapter() {
public void windowClosing(WindowEvent e) {
System.exit(0);
}
};
jFrame.addWindowListener(wl);
jFrame.pack();
jFrame.setVisible(true);
}
// Button handling.
public void actionPerformed(ActionEvent e) {
numClicks++;
jLabel.setText(labelPrefix + numClicks);
}
public static void main(String[] args) {
HelloSwing helloSwing = new HelloSwing();
helloSwing.go();
}
}
BorderFactory.createEmptyBorder方法要求四个参数都是int形,
你的12.30是double。
改成12或者13都行。