2015.04.17-3 按鈕顯示yes

按鈕顯示yes

import java.awt.*; import java.awt.event.*; import javax.swing.*; public class Calculator2 implements ActionListener { public static void main(String[] args) { new Calculator2(); } public Calculator2() { JFrame window=new JFrame("Calculator2"); window.setDefaultLookAndFeelDecorated(true); window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); window.setLayout(new GridLayout(3,3)); JPanel jplPanel = new JPanel(); jplPanel.setLayout(new GridLayout(3,3)); JButton button[]=new JButton[10]; for (int i = 1; i <= 9; i++) { button[i] = new JButton(); button[i].setSize(50,50); button[i].setText(Integer.toString(i)); button[i].setActionCommand("d1"); button[i].addActionListener(this); jplPanel.add(button[i]); } window.getContentPane().add(jplPanel, BorderLayout.CENTER); window.setSize(500,500); window.setVisible(true); } public void actionPerformed(ActionEvent e) { String cmd = e.getActionCommand(); if (cmd == "d1") { System.out.println("Yes...."); } } } class AdapterDemo extends WindowAdapter { public void windowClosing(WindowEvent e) { System.exit(0); } }