使用这样的代码处理JFrame的好方法是什么?我想处理Window出口和窗口关闭。
我知道我们不应该使用System.exit();
public class JavaCellularAutomataSquare {
public static final String TITLE = "Cellular Automata - Squaring Example";
private int maxWidth = 600;
private int maxHeight = 600;
public void launch() {
final JFrame frame = new JFrame(TITLE);
frame.setLocation(20, 20);
frame.setPreferredSize(new Dimension(maxWidth, maxHeight));
frame.setResizable(false);
frame.setFocusable(true);
final JPanel panel = new JPanel();
panel.setLocation(20, 20);
panel.setVisible(true);
panel.setPreferredSize(new Dimension(maxWidth, maxHeight));
panel.setFocusable(true);
panel.setBackground(Color.white);
// Panel setup, toggle visibility on frame
frame.add(panel);
frame.pack();
frame.setVisible(true);
}
}
答案 0 :(得分:10)
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class ClosingFrame extends JFrame {
private JMenuBar MenuBar = new JMenuBar();
private JFrame frame = new JFrame();
private static final long serialVersionUID = 1L;
private JMenu File = new JMenu("File");
private JMenuItem Exit = new JMenuItem("Exit");
public ClosingFrame() {
File.add(Exit);
MenuBar.add(File);
Exit.addActionListener(new ExitListener());
WindowListener exitListener = new WindowAdapter() {
@Override
public void windowClosing(WindowEvent e) {
int confirm = JOptionPane.showOptionDialog(frame,
"Are You Sure to Close this Application?",
"Exit Confirmation", JOptionPane.YES_NO_OPTION,
JOptionPane.QUESTION_MESSAGE, null, null, null);
if (confirm == JOptionPane.YES_OPTION) {
System.exit(0);
}
}
};
frame.addWindowListener(exitListener);
frame.setDefaultCloseOperation(EXIT_ON_CLOSE);
frame.setJMenuBar(MenuBar);
frame.setPreferredSize(new Dimension(400, 300));
frame.setLocation(100, 100);
frame.pack();
frame.setVisible(true);
}
private class ExitListener implements ActionListener {
@Override
public void actionPerformed(ActionEvent e) {
int confirm = JOptionPane.showOptionDialog(frame,
"Are You Sure to Close this Application?",
"Exit Confirmation", JOptionPane.YES_NO_OPTION,
JOptionPane.QUESTION_MESSAGE, null, null, null);
if (confirm == JOptionPane.YES_OPTION) {
System.exit(0);
}
}
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
@Override
public void run() {
ClosingFrame cf = new ClosingFrame();
}
});
}
}
答案 1 :(得分:8)
JFrame.setDefaultCloseOperation(DISPOSE_ON_CLOSE)
释放资源。您可以在Java教程here.
如果您对选项感到好奇,可以在WindowConstants界面中定义您可以在方法中使用的可能参数。
答案 2 :(得分:3)
如果您需要在关闭应用程序时执行某些操作,那么您需要一个 shut down hook。看看这个post。
答案 3 :(得分:1)
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);