利用简单的自由布局实现实现下来列表式菜单

 

利用了一点点自由布局可以很方便的自由添加多个菜单项，代码如下：

import java.awt.Color;
import java.awt.Dimension;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.GridLayout;
import java.awt.Toolkit;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;

import javax.swing.GroupLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.border.LineBorder;

public class SimpleMenulist extends JFrame implements MouseListener {

	private static final long serialVersionUID = -6050868817749702480L;
	/**
	 * @param args
	 */
	private JButton menulistButton1;
	private JLabel menulistButton1_1;
	private JLabel menulistButton1_2;
	private JLabel menulistButton1_3;

	private JButton menulistButton2;
	private JLabel menulistButton2_1;
	private JLabel menulistButton2_2;
	private JLabel menulistButton2_3;

	private JButton menulistButton3;
	private JLabel menulistButton3_1;
	private JLabel menulistButton3_2;
	private JLabel menulistButton3_3;

	private JButton menulistButton4;
	private JLabel menulistButton4_1;
	private JLabel menulistButton4_2;
	private JLabel menulistButton4_3;

	private JButton menulistButton5;
	private JLabel menulistButton5_1;
	private JLabel menulistButton5_2;
	private JLabel menulistButton5_3;

	private JPanel mainPanel;

	private JPanel buttonPanel1;
	private JPanel buttonPanel2;
	private JPanel buttonPanel3;
	private JPanel buttonPanel4;
	private JPanel buttonPanel5;

	// 基本思想：4（按钮+标签+GridLayout） * 4（面板+GridBagLayout） * 1（面板+自由布局）
	public SimpleMenulist(String title) {
		super(title);
		setDefaultCloseOperation(EXIT_ON_CLOSE);
		mainPanel = new JPanel();
		GroupLayout layout = new GroupLayout(getContentPane());
		getContentPane().setLayout(layout);
		layout.setHorizontalGroup(layout.createParallelGroup(
				GroupLayout.Alignment.LEADING).addComponent(mainPanel));
		layout.setVerticalGroup(layout.createParallelGroup(
				GroupLayout.Alignment.LEADING).addGroup(
				layout.createSequentialGroup().addComponent(mainPanel)
						.addContainerGap(500, Short.MAX_VALUE)));

		add(mainPanel);

		mainPanel.setLayout(new GridBagLayout());

		buttonPanel1 = new JPanel();
		buttonPanel2 = new JPanel();
		buttonPanel3 = new JPanel();
		buttonPanel4 = new JPanel();
		buttonPanel5 = new JPanel();

		GridBagConstraints GBC = new GridBagConstraints();
		GBC.gridx = 0;
		GBC.gridy = 0;
		GBC.fill = GridBagConstraints.BOTH;
		mainPanel.add(buttonPanel1, GBC);

		GBC.gridx = 0;
		GBC.gridy = 1;
		mainPanel.add(buttonPanel2, GBC);

		GBC.gridx = 0;
		GBC.gridy = 2;
		mainPanel.add(buttonPanel3, GBC);

		GBC.gridx = 0;
		GBC.gridy = 3;
		mainPanel.add(buttonPanel4, GBC);

		GBC.gridx = 0;
		GBC.gridy = 4;
		mainPanel.add(buttonPanel5, GBC);

		buttonPanel1.setLayout(new GridLayout(1, 1));
		buttonPanel2.setLayout(new GridLayout(1, 1));
		buttonPanel3.setLayout(new GridLayout(1, 1));
		buttonPanel4.setLayout(new GridLayout(1, 1));
		buttonPanel5.setLayout(new GridLayout(1, 1));

		menulistButton1 = new JButton("Ben Zeph Menulist1_0");
		menulistButton1_1 = new JLabel("menulist1_1");
		menulistButton1_2 = new JLabel("menulist1_2");
		menulistButton1_3 = new JLabel("menulist1_3");

		menulistButton2 = new JButton("Ben Zeph Menulist2_0");
		menulistButton2_1 = new JLabel("menulist2_1");
		menulistButton2_2 = new JLabel("menulist2_2");
		menulistButton2_3 = new JLabel("menulist2_3");

		menulistButton3 = new JButton("Ben Zeph Menulist3_0");
		menulistButton3_1 = new JLabel("menulist3_1");
		menulistButton3_2 = new JLabel("menulist3_2");
		menulistButton3_3 = new JLabel("menulist3_3");

		menulistButton4 = new JButton("Ben Zeph Menulist4_0");
		menulistButton4_1 = new JLabel("menulist4_1");
		menulistButton4_2 = new JLabel("menulist4_2");
		menulistButton4_3 = new JLabel("menulist4_3");

		menulistButton5 = new JButton("Ben Zeph Menulist5_0");
		menulistButton5_1 = new JLabel("menulist5_1");
		menulistButton5_2 = new JLabel("menulist5_2");
		menulistButton5_3 = new JLabel("menulist5_3");

		buttonPanel1.add(menulistButton1);
		buttonPanel2.add(menulistButton2);
		buttonPanel3.add(menulistButton3);
		buttonPanel4.add(menulistButton4);
		buttonPanel5.add(menulistButton5);

		menulistButton1_1.setHorizontalAlignment((int) CENTER_ALIGNMENT);
		menulistButton1_2.setHorizontalAlignment((int) CENTER_ALIGNMENT);
		menulistButton1_3.setHorizontalAlignment((int) CENTER_ALIGNMENT);
		menulistButton2_1.setHorizontalAlignment((int) CENTER_ALIGNMENT);
		menulistButton2_2.setHorizontalAlignment((int) CENTER_ALIGNMENT);
		menulistButton2_3.setHorizontalAlignment((int) CENTER_ALIGNMENT);
		menulistButton3_1.setHorizontalAlignment((int) CENTER_ALIGNMENT);
		menulistButton3_2.setHorizontalAlignment((int) CENTER_ALIGNMENT);
		menulistButton3_3.setHorizontalAlignment((int) CENTER_ALIGNMENT);
		menulistButton4_1.setHorizontalAlignment((int) CENTER_ALIGNMENT);
		menulistButton4_2.setHorizontalAlignment((int) CENTER_ALIGNMENT);
		menulistButton4_3.setHorizontalAlignment((int) CENTER_ALIGNMENT);
		menulistButton5_1.setHorizontalAlignment((int) CENTER_ALIGNMENT);
		menulistButton5_2.setHorizontalAlignment((int) CENTER_ALIGNMENT);
		menulistButton5_3.setHorizontalAlignment((int) CENTER_ALIGNMENT);

		menulistButton1.addMouseListener(this);
		menulistButton2.addMouseListener(this);
		menulistButton3.addMouseListener(this);
		menulistButton4.addMouseListener(this);
		menulistButton5.addMouseListener(this);
		menulistButton1_1.addMouseListener(this);
		menulistButton1_2.addMouseListener(this);
		menulistButton1_3.addMouseListener(this);
		menulistButton2_1.addMouseListener(this);
		menulistButton2_2.addMouseListener(this);
		menulistButton2_3.addMouseListener(this);
		menulistButton3_1.addMouseListener(this);
		menulistButton3_2.addMouseListener(this);
		menulistButton3_3.addMouseListener(this);
		menulistButton4_1.addMouseListener(this);
		menulistButton4_2.addMouseListener(this);
		menulistButton4_3.addMouseListener(this);
		menulistButton5_1.addMouseListener(this);
		menulistButton5_2.addMouseListener(this);
		menulistButton5_3.addMouseListener(this);
		// 设置整体框架的位置
		Dimension frameSize = getPreferredSize();
		Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
		setLocation(screenSize.width / 2 - frameSize.width / 2,
				screenSize.height / 2 - frameSize.height / 2);
		pack();
	}

	public void repaintUpdateUI() {
		buttonPanel1.repaint();
		buttonPanel1.updateUI();
		buttonPanel2.repaint();
		buttonPanel2.updateUI();
		buttonPanel3.repaint();
		buttonPanel3.updateUI();
		buttonPanel4.repaint();
		buttonPanel4.updateUI();
		buttonPanel5.repaint();
		buttonPanel5.updateUI();
	}

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		java.awt.EventQueue.invokeLater(new Runnable() {
			public void run() {
				new SimpleMenulist("menulistList - Ben Zeph").setVisible(true);
			}
		});
	}

	@Override
	public void mouseClicked(MouseEvent e) {
		// TODO Auto-generated method stub
		if (menulistButton1.equals(e.getSource())) {
			if (!menulistButton1_1.isValid()) {
				buttonPanel1.removeAll();
				buttonPanel1.setLayout(new GridLayout(4, 1));
				buttonPanel1.add(menulistButton1);
				buttonPanel1.add(menulistButton1_1);
				buttonPanel1.add(menulistButton1_2);
				buttonPanel1.add(menulistButton1_3);
			} else if (menulistButton1_1.isValid()) {
				buttonPanel1.removeAll();
				buttonPanel1.setLayout(new GridLayout(1, 1));
				buttonPanel1.add(menulistButton1);
			}
			repaintUpdateUI();
		} else if (menulistButton2.equals(e.getSource())) {
			if (!menulistButton2_1.isValid()) {
				buttonPanel2.removeAll();
				buttonPanel2.setLayout(new GridLayout(4, 1));
				buttonPanel2.add(menulistButton2);
				buttonPanel2.add(menulistButton2_1);
				buttonPanel2.add(menulistButton2_2);
				buttonPanel2.add(menulistButton2_3);
			} else if (menulistButton2_1.isValid()) {
				buttonPanel2.removeAll();
				buttonPanel2.setLayout(new GridLayout(1, 1));
				buttonPanel2.add(menulistButton2);
			}
			repaintUpdateUI();
		} else if (menulistButton3.equals(e.getSource())) {
			if (!menulistButton3_1.isValid()) {
				buttonPanel3.removeAll();
				buttonPanel3.setLayout(new GridLayout(4, 1));
				buttonPanel3.add(menulistButton3);
				buttonPanel3.add(menulistButton3_1);
				buttonPanel3.add(menulistButton3_2);
				buttonPanel3.add(menulistButton3_3);
			} else if (menulistButton3_1.isValid()) {
				buttonPanel3.removeAll();
				buttonPanel3.setLayout(new GridLayout(1, 1));
				buttonPanel3.add(menulistButton3);
			}
			repaintUpdateUI();
		} else if (menulistButton4.equals(e.getSource())) {
			if (!menulistButton4_1.isValid()) {
				buttonPanel4.removeAll();
				buttonPanel4.setLayout(new GridLayout(4, 1));
				buttonPanel4.add(menulistButton4);
				buttonPanel4.add(menulistButton4_1);
				buttonPanel4.add(menulistButton4_2);
				buttonPanel4.add(menulistButton4_3);
			} else if (menulistButton4_1.isValid()) {
				buttonPanel4.removeAll();
				buttonPanel4.setLayout(new GridLayout(1, 1));
				buttonPanel4.add(menulistButton4);
			}
			repaintUpdateUI();
		} else if (menulistButton5.equals(e.getSource())) {
			if (!menulistButton5_1.isValid()) {
				buttonPanel5.removeAll();
				buttonPanel5.setLayout(new GridLayout(4, 1));
				buttonPanel5.add(menulistButton5);
				buttonPanel5.add(menulistButton5_1);
				buttonPanel5.add(menulistButton5_2);
				buttonPanel5.add(menulistButton5_3);
			} else if (menulistButton5_1.isValid()) {
				buttonPanel5.removeAll();
				buttonPanel5.setLayout(new GridLayout(1, 1));
				buttonPanel5.add(menulistButton5);
			}
			repaintUpdateUI();
		}
	}

	@Override
	public void mouseEntered(MouseEvent e) {
		// TODO Auto-generated method stub
		if (menulistButton1_1.equals(e.getSource())) {
			menulistButton1_1.setBorder(new LineBorder(Color.BLACK));
			menulistButton1_1.setBackground(Color.green);
		} else if (menulistButton1_2.equals(e.getSource())) {
			menulistButton1_2.setBorder(new LineBorder(Color.BLACK));
		} else if (menulistButton1_3.equals(e.getSource())) {
			menulistButton1_3.setBorder(new LineBorder(Color.BLACK));
		} else if (menulistButton2_1.equals(e.getSource())) {
			menulistButton2_1.setBorder(new LineBorder(Color.BLACK));
		} else if (menulistButton2_2.equals(e.getSource())) {
			menulistButton2_2.setBorder(new LineBorder(Color.BLACK));
		} else if (menulistButton2_3.equals(e.getSource())) {
			menulistButton2_3.setBorder(new LineBorder(Color.BLACK));
		} else if (menulistButton3_1.equals(e.getSource())) {
			menulistButton3_1.setBorder(new LineBorder(Color.BLACK));
		} else if (menulistButton3_2.equals(e.getSource())) {
			menulistButton3_2.setBorder(new LineBorder(Color.BLACK));
		} else if (menulistButton3_3.equals(e.getSource())) {
			menulistButton3_3.setBorder(new LineBorder(Color.BLACK));
		} else if (menulistButton4_1.equals(e.getSource())) {
			menulistButton4_1.setBorder(new LineBorder(Color.BLACK));
		} else if (menulistButton4_2.equals(e.getSource())) {
			menulistButton4_2.setBorder(new LineBorder(Color.BLACK));
		} else if (menulistButton4_3.equals(e.getSource())) {
			menulistButton4_3.setBorder(new LineBorder(Color.BLACK));
		} else if (menulistButton5_1.equals(e.getSource())) {
			menulistButton5_1.setBorder(new LineBorder(Color.BLACK));
		} else if (menulistButton5_2.equals(e.getSource())) {
			menulistButton5_2.setBorder(new LineBorder(Color.BLACK));
		} else if (menulistButton5_3.equals(e.getSource())) {
			menulistButton5_3.setBorder(new LineBorder(Color.BLACK));
		}
	}

	@Override
	public void mouseExited(MouseEvent e) {
		// TODO Auto-generated method stub
		if (menulistButton1_1.equals(e.getSource())) {
			menulistButton1_1.setBorder(null);
		} else if (menulistButton1_2.equals(e.getSource())) {
			menulistButton1_2.setBorder(null);
		} else if (menulistButton1_3.equals(e.getSource())) {
			menulistButton1_3.setBorder(null);
		} else if (menulistButton2_1.equals(e.getSource())) {
			menulistButton2_1.setBorder(null);
		} else if (menulistButton2_2.equals(e.getSource())) {
			menulistButton2_2.setBorder(null);
		} else if (menulistButton2_3.equals(e.getSource())) {
			menulistButton2_3.setBorder(null);
		} else if (menulistButton3_1.equals(e.getSource())) {
			menulistButton3_1.setBorder(null);
		} else if (menulistButton3_2.equals(e.getSource())) {
			menulistButton3_2.setBorder(null);
		} else if (menulistButton3_3.equals(e.getSource())) {
			menulistButton3_3.setBorder(null);
		} else if (menulistButton4_1.equals(e.getSource())) {
			menulistButton4_1.setBorder(null);
		} else if (menulistButton4_2.equals(e.getSource())) {
			menulistButton4_2.setBorder(null);
		} else if (menulistButton4_3.equals(e.getSource())) {
			menulistButton4_3.setBorder(null);
		} else if (menulistButton5_1.equals(e.getSource())) {
			menulistButton5_1.setBorder(null);
		} else if (menulistButton5_2.equals(e.getSource())) {
			menulistButton5_2.setBorder(null);
		} else if (menulistButton5_3.equals(e.getSource())) {
			menulistButton5_3.setBorder(null);
		}
	}

	@Override
	public void mousePressed(MouseEvent e) {
		// TODO Auto-generated method stub
		if (menulistButton1_1.equals(e.getSource())) {
			menulistButton1_1.setForeground(Color.RED);
		} else if (menulistButton1_2.equals(e.getSource())) {
			menulistButton1_2.setForeground(Color.RED);
		} else if (menulistButton1_3.equals(e.getSource())) {
			menulistButton1_3.setForeground(Color.RED);
		} else if (menulistButton2_1.equals(e.getSource())) {
			menulistButton2_1.setForeground(Color.RED);
		} else if (menulistButton2_2.equals(e.getSource())) {
			menulistButton2_2.setForeground(Color.RED);
		} else if (menulistButton2_3.equals(e.getSource())) {
			menulistButton2_3.setForeground(Color.RED);
		} else if (menulistButton3_1.equals(e.getSource())) {
			menulistButton3_1.setForeground(Color.RED);
		} else if (menulistButton3_2.equals(e.getSource())) {
			menulistButton3_2.setForeground(Color.RED);
		} else if (menulistButton3_3.equals(e.getSource())) {
			menulistButton3_3.setForeground(Color.RED);
		} else if (menulistButton4_1.equals(e.getSource())) {
			menulistButton4_1.setForeground(Color.RED);
		} else if (menulistButton4_2.equals(e.getSource())) {
			menulistButton4_2.setForeground(Color.RED);
		} else if (menulistButton4_3.equals(e.getSource())) {
			menulistButton4_3.setForeground(Color.RED);
		} else if (menulistButton5_1.equals(e.getSource())) {
			menulistButton5_1.setForeground(Color.RED);
		} else if (menulistButton5_2.equals(e.getSource())) {
			menulistButton5_2.setForeground(Color.RED);
		} else if (menulistButton5_3.equals(e.getSource())) {
			menulistButton5_3.setForeground(Color.RED);
		}
	}

	@Override
	public void mouseReleased(MouseEvent e) {
		// TODO Auto-generated method stub
		if (menulistButton1_1.equals(e.getSource())) {
			menulistButton1_1.setForeground(Color.DARK_GRAY);
		} else if (menulistButton1_2.equals(e.getSource())) {
			menulistButton1_2.setForeground(Color.DARK_GRAY);
		} else if (menulistButton1_3.equals(e.getSource())) {
			menulistButton1_3.setForeground(Color.DARK_GRAY);
		} else if (menulistButton2_1.equals(e.getSource())) {
			menulistButton2_1.setForeground(Color.DARK_GRAY);
		} else if (menulistButton2_2.equals(e.getSource())) {
			menulistButton2_2.setForeground(Color.DARK_GRAY);
		} else if (menulistButton2_3.equals(e.getSource())) {
			menulistButton2_3.setForeground(Color.DARK_GRAY);
		} else if (menulistButton3_1.equals(e.getSource())) {
			menulistButton3_1.setForeground(Color.DARK_GRAY);
		} else if (menulistButton3_2.equals(e.getSource())) {
			menulistButton3_2.setForeground(Color.DARK_GRAY);
		} else if (menulistButton3_3.equals(e.getSource())) {
			menulistButton3_3.setForeground(Color.DARK_GRAY);
		} else if (menulistButton4_1.equals(e.getSource())) {
			menulistButton4_1.setForeground(Color.DARK_GRAY);
		} else if (menulistButton4_2.equals(e.getSource())) {
			menulistButton4_2.setForeground(Color.DARK_GRAY);
		} else if (menulistButton4_3.equals(e.getSource())) {
			menulistButton4_3.setForeground(Color.DARK_GRAY);
		} else if (menulistButton5_1.equals(e.getSource())) {
			menulistButton5_1.setForeground(Color.DARK_GRAY);
		} else if (menulistButton5_2.equals(e.getSource())) {
			menulistButton5_2.setForeground(Color.DARK_GRAY);
		} else if (menulistButton5_3.equals(e.getSource())) {
			menulistButton5_3.setForeground(Color.DARK_GRAY);
		}
	}

}