import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class myExample implements ActionListener{ JPanel top,bottom,mainPanel;
JButton addButton,subButton;
JTextField text;
public myExample(){
addButton = new JButton("add");
subButton = new JButton("sub");
text = new JTextField("呵呵,我也不知道写什么");
top = new JPanel();
bottom = new JPanel();
mainPanel = new JPanel(new GridLayout(2,1));
top.setOpaque(true);
bottom.setOpaque(true);
top.add(addButton);
top.add(subButton);
bottom.add(text);
mainPanel.setOpaque(true);
mainPanel.add(top);
mainPanel.add(bottom);
addButton.addActionListener(this);
subButton.addActionListener(this);
}
public void actionPerformed(ActionEvent e){
text.setText("+ or -");
}
private static void createAndShowGUI(){
JFrame.setDefaultLookAndFeelDecorated(true);
JFrame frame = new JFrame("My Example");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
myExample contentPane = new myExample();
contentPane.mainPanel.setOpaque(true);
frame.setContentPane(contentPane.mainPanel);
frame.pack();
frame.setVisible(true);
}
public static void main(String[] args) {
myExample.createAndShowGUI();
}}
这个程序中的两个按钮共用一个actionPerformed(),怎样才能我点加号按钮出加号,点减号出减号啊,帮帮忙啊
import java.awt.*;
import java.awt.event.*;
public class myExample implements ActionListener{ JPanel top,bottom,mainPanel;
JButton addButton,subButton;
JTextField text;
public myExample(){
addButton = new JButton("add");
subButton = new JButton("sub");
text = new JTextField("呵呵,我也不知道写什么");
top = new JPanel();
bottom = new JPanel();
mainPanel = new JPanel(new GridLayout(2,1));
top.setOpaque(true);
bottom.setOpaque(true);
top.add(addButton);
top.add(subButton);
bottom.add(text);
mainPanel.setOpaque(true);
mainPanel.add(top);
mainPanel.add(bottom);
addButton.addActionListener(this);
subButton.addActionListener(this);
}
public void actionPerformed(ActionEvent e){
text.setText("+ or -");
}
private static void createAndShowGUI(){
JFrame.setDefaultLookAndFeelDecorated(true);
JFrame frame = new JFrame("My Example");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
myExample contentPane = new myExample();
contentPane.mainPanel.setOpaque(true);
frame.setContentPane(contentPane.mainPanel);
frame.pack();
frame.setVisible(true);
}
public static void main(String[] args) {
myExample.createAndShowGUI();
}}
这个程序中的两个按钮共用一个actionPerformed(),怎样才能我点加号按钮出加号,点减号出减号啊,帮帮忙啊
text.setText("+");
else if(e.getSource() == subButton)
text.setText("-");
}