求助，为何不能弹出窗口

Question

import java.awt.Color;import java.awt.Container;import java.awt.event.ActionEvent;import java.awt.event.ActionListener;import javax.swing.JButton;import javax.swing.JDialog;import javax.swing.JFrame;import javax.swing.JLabel;import javax.swing.SwingConstants;import javax.swing.WindowConstants;class MyDialog extends JDialog{ public MyDialog(MyFrame frame){ super(frame,"第一个Jdialog窗口",true); Container container=getContentPane(); container.add(new JLabel("这是与各对话框")); setBounds(120,120,100,100);}}public class MyFrame extends JFrame { public static void main(String[] args) { new MyFrame(); } public MyFrame(){ Container container=getContentPane(); container.setLayout(null); JLabel jl=new JLabel("这是一个JFrame窗口"); jl.setHorizontalAlignment(SwingConstants.CENTER); container.add(jl); JButton bl=new JButton("弹出对话框"); bl.setBounds(10,10,100,21); bl.addActionListener(new ActionListener(){ public void actionPerformed(ActionEvent e){ new MyDialog(MyFrame.this).setVisible(true); } }); container.add(bl); bl.setVisible(true); jl.setVisible(true); container.setBackground(Color.blue); setDefaultCloseOperation(WindowConstants.DISPOSE_ON_CLOSE); } }

Answer 1

你这一行注释都不带写的啊,

Answer 2

我的神啊，，各位师兄师姐们求助啊