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最近在看金旭日老师的Java课程，为后期的通过Android实现某个项目做准备：

目标：完成  在对象之间“广播消息”http://www.jinxuliang.com/course/PPT/Show/5469992f137e420664f62752

参考：http://www.jinxuliang.com/course/PPT/Show/54699909137e420664f62751

界面依然用的是Swing Designer设计的：

//功能：在对象间“广播消息”//http://www.jinxuliang.com/course/PPT/Show/5469992f137e420664f62752import java.awt.EventQueue;import javax.swing.JFrame;import javax.swing.JPanel;import javax.swing.JTextField;import javax.swing.border.EmptyBorder;import javax.swing.JButton;import java.awt.Font;import java.awt.event.ActionListener;import java.awt.event.ActionEvent;public class GUITest2 extends JFrame {	private JPanel contentPane;	/**	 * Launch the application.	 */	public static void main(String[] args) {		EventQueue.invokeLater(new Runnable() {			public void run() {				try {					GUITest2 frame = new GUITest2();					frame.setVisible(true);				} catch (Exception e) {					e.printStackTrace();				}			}		});	}	/**	 * Create the frame.	 */	public GUITest2() {		setTitle("\u4E3B\u7A97\u4F53");		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);		setBounds(100, 100, 450, 300);		contentPane = new JPanel();		contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));		setContentPane(contentPane);		contentPane.setLayout(null);				JButton btnNewButton_Counter = new JButton("\u70B9\u51FB\u589E\u52A0\u8BA1\u6570\u503C");		btnNewButton_Counter.setFont(new Font("微软雅黑", Font.PLAIN, 16));		btnNewButton_Counter.setBounds(93, 121, 246, 48);		contentPane.add(btnNewButton_Counter);				JButton btnNewButton = new JButton("\u70B9\u51FB\u65B0\u5EFA\u4E00\u4E2A\u4ECE\u7A97\u4F53\u5BF9\u8C61");		btnNewButton.addActionListener(new ActionListener() {			public void actionPerformed(ActionEvent e) {				BlankFrame frame=new BlankFrame(btnNewButton_Counter);//这里是要点：新的窗体的构造函数接收一个JButton对象				frame.setVisible(true);//显示			}		});		btnNewButton.setFont(new Font("微软雅黑", Font.PLAIN, 16));		btnNewButton.setBounds(93, 36, 246, 48);		contentPane.add(btnNewButton);		}		/**	   A blank frame that can be countered by clicking a button.	*/	static class BlankFrame extends JFrame{		public BlankFrame(JButton Counter){			counterTitle++;			setTitle("从窗体"+counterTitle);			setSize(DEFAULT_WIDTH, DEFAULT_HEIGHT);			setLocation(SPACING * counterTitle, SPACING * counterTitle); 						JTextField Text=new JTextField();			Text.setEditable(false);//不能编辑			add(Text);//添加文本框						String str=Integer.toString(counterNumber);			Text.setText(str);//设置文本框默认值						counterListener=new ActionListener() {								@Override				public void actionPerformed(ActionEvent e) {					// TODO Auto-generated method stub					counterNumber++;					String str=Integer.toString(counterNumber);					Text.setText(str);//修改按钮响应事件				}			};			Counter.addActionListener(counterListener);		}		private ActionListener counterListener;		private static int counterTitle = 0;		private  int counterNumber = 0;		public static final int DEFAULT_WIDTH = 200;		public static final int DEFAULT_HEIGHT = 150; 		public static final int SPACING = 40;	}}