java中如何把一个面板封装成一个类添加到窗口？

import java.awt.event.ActionEvent

import java.awt.event.ActionListener

import javax.swing.JButton

import javax.swing.JFrame

import javax.swing.JPanel

public class Demo1 {

    /*

     * 在主方法中创建窗口对象。

     * 画板里的组件和监听要在画板类里面写好。

     * 主方法只管创建不同的画板对象往里添加就行了。

     * 

     */

    public static void main(String[] args) {

        MyFrame frame = new MyFrame()

        MyPanelOne panel1 = new MyPanelOne()

        frame.add(panel1)

    }

}

class MyFrame extends JFrame { // 主界面

    public MyFrame() {

        this.setTitle("主界面")

        this.setSize(500, 500)

        this.setVisible(true)

    }

    void addPanel(MyPanelOne panel) { // 传递画板的函数

        this.setContentPane(panel)

        this.setVisible(true)

    }

}

class MyPanelOne extends JPanel { // 画板1

    public MyPanelOne() {

        createButton()

    }

    private void createButton() {

        JButton b1 = new JButton("按钮一")

        this.add(b1)

        b1.addActionListener(new ActionListener() {

            public void actionPerformed(ActionEvent e) {

                System.out.println("hello")

            }

        })

    }

}

class ChildWindos extends JFrame{

JButton b1

public ChildWindos(){

super("字体")

this.setResizable(false)

this.setVisible(true)

this.setSize(300,300)

this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE)

this.setLayout(null)

b1=new JButton("JBT1")

b1.setSize(100,100)

b1.setLocation(100,100)

this.add(b1)

}

}

你的父窗体怎么加的按钮，子窗体就怎么加，跟那无区别

/**

 * 把代码复制到文件，可以运行。

 */

import java.awt.BorderLayout

import java.awt.Color

import java.awt.Component

import java.awt.Font

import java.awt.Graphics

import java.awt.Graphics2D

import java.awt.Rectangle

import java.awt.Transparency

import java.awt.event.WindowAdapter

import java.awt.event.WindowEvent

import java.awt.image.BufferedImage

import javax.swing.Icon

import javax.swing.ImageIcon

import javax.swing.JDialog

import javax.swing.JLabel

import javax.swing.JPanel

import javax.swing.JScrollPane

import javax.swing.JTree

import javax.swing.UIManager

import javax.swing.tree.DefaultMutableTreeNode

import javax.swing.tree.TreeCellRenderer

/**

 *

 * @author beans

 */

public class TreeMain {

    public static void main(String[] args) {

        new TreeMain().showDialog()

    }

    public TreeMain() {

    }

    /**

     * 显示窗口

     */

    private void showDialog() {

        JDialog dialog = new JDialog()

        dialog.setBounds(new Rectangle(50, 50, 380, 280))

        dialog.setTitle("演示树")

        dialog.addWindowListener(new WindowAdapter() {

            @Override

            public void windowClosing(WindowEvent e) {

                dialog.setVisible(false)

                dialog.dispose()

            }

        })

        dialog.add(this.getPanel(), BorderLayout.CENTER)

        dialog.setVisible(true)

    }

    private JPanel getPanel() {

        JPanel panel = new JPanel()

        JScrollPane treePanel = new JScrollPane()

        treePanel.setViewportView(this.getTree())

        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(panel)

        panel.setLayout(layout)

        layout.setHorizontalGroup(

                layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)

                .addGroup(layout.createSequentialGroup()

                        .addContainerGap()

                        .addComponent(treePanel, javax.swing.GroupLayout.DEFAULT_SIZE, 380, Short.MAX_VALUE)

                        .addContainerGap())

        )

        layout.setVerticalGroup(

                layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)

                .addGroup(layout.createSequentialGroup()

                        .addContainerGap()

                        .addComponent(treePanel, javax.swing.GroupLayout.PREFERRED_SIZE, 272, javax.swing.GroupLayout.PREFERRED_SIZE)

                        .addContainerGap(18, Short.MAX_VALUE))

        )

        panel.add(treePanel, BorderLayout.CENTER)

        return panel

    }

    /**

     * 取得树。

     *

     * @return

     */

    private JTree getTree() {

        DefaultMutableTreeNode root = new DefaultMutableTreeNode()

        root.add(this.getNode())

        root.add(this.getNode())

        root.add(this.getNode())

        JTree jtree = new JTree(root)

        jtree.setRootVisible(false)

        jtree.setCellRenderer(new CTreeCellRenderer())

        jtree.expandRow(1)

        return jtree

    }

    /**

     * 取得树节点。

     *

     * @return

     */

    private DefaultMutableTreeNode getNode() {

        DefaultMutableTreeNode node = new DefaultMutableTreeNode(new NodeObject(true, "节"))

        for (int i = 0 i < 5 i++) {

            DefaultMutableTreeNode leaf = new DefaultMutableTreeNode(new NodeObject(false, "叶" + i))

            node.add(leaf)

        }

        return node

    }

    /**

     * 树节点和树叶，关联对象。

     */

    class NodeObject {

        boolean isNode

        String name

        /**

         *

         * @param isNode the value of isNode

         * @param name the value of name

         */

        NodeObject(boolean isNode, String name) {

            this.isNode = isNode

            this.name = name

        }

        /**

         * 图标

         *

         * @param isSelect 选中节点时返回不同的图标。

         * @return

         */

        ImageIcon getIcon(boolean isSelect) {

            int wh = 20

            BufferedImage image = new BufferedImage(wh, wh, BufferedImage.TYPE_INT_ARGB)

            Graphics2D g2 = image.createGraphics()

            image = g2.getDeviceConfiguration().createCompatibleImage(wh, wh, Transparency.TRANSLUCENT)

            Graphics2D g2d = image.createGraphics()

            Font font = new Font("Dialog", Font.PLAIN, wh - 4)

            g2d.setFont(font)

            g2d.setBackground(Color.WHITE)

            g2d.setColor(Color.BLACK)

            g2d.drawString(isSelect ? " S " : " N ", 0, wh - 1)

            g2d.setColor(this.isNode ? Color.RED : Color.YELLOW)

            g2d.drawLine(0, 5, wh, 5)

            g2d.drawLine(0, 10, wh, 10)

            g2d.drawLine(0, 15, wh, 15)

            g2d.dispose()

            g2.dispose()

            return new ImageIcon(image)

        }

        String getName() {

            return this.name

        }

    }

    /**

     * 树渲染器

     */

    protected class CTreeCellRenderer extends JLabel implements TreeCellRenderer {

        protected Color m_textSelectionColor

        protected Color m_textNonSelectionColor

        protected Color m_bkSelectionColor

        protected Color m_bkNonSelectionColor

        protected Color m_borderSelectionColor

        protected boolean m_selected

        public CTreeCellRenderer() {

            m_textSelectionColor = UIManager.getColor("Tree.selectionForeground")

            m_textNonSelectionColor = UIManager.getColor("Tree.textForeground")

            m_bkSelectionColor = UIManager.getColor("Tree.selectionBackground")

            m_bkNonSelectionColor = UIManager.getColor("Tree.textBackground")

            m_borderSelectionColor = UIManager.getColor("Tree.selectionBorderColor")

        }

        @Override

        public Component getTreeCellRendererComponent(JTree tree, Object value,

                boolean selected, boolean expanded, boolean leaf, int row, boolean hasFocus) {

            DefaultMutableTreeNode node = (DefaultMutableTreeNode) value

            NodeObject obj = (NodeObject) node.getUserObject()

            this.setIcon(obj.getIcon(selected))

            this.setText("  " + obj.getName() + " ")

            this.setForeground(selected ? m_textSelectionColor : m_textNonSelectionColor)

            this.setBackground(selected ? m_bkSelectionColor : m_bkNonSelectionColor)

            this.m_selected = selected

            return this

        }

        @Override

        public void paint(Graphics g) {

            Color bColor = this.getBackground()

            Icon icon = this.getIcon()

            g.setColor(bColor)

            int offset = 0

            if (icon != null && getText() != null) {

                offset = (icon.getIconWidth() + this.getIconTextGap())

            }

            g.fillRect(offset, 0, this.getWidth() - 1 - offset, this.getHeight() - 1)

            if (this.m_selected) {

                g.setColor(this.m_borderSelectionColor)

                g.drawRect(offset, 0, this.getWidth() - 1 - offset, this.getHeight() - 1)

            }

            super.paint(g)

        }

    }

}

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