一個簡單的桌面應用程序框架示例（Java SE9）

1.　　創建主窗體界面

package com.ys;

import java.awt.Dimension;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;

import javax.swing.Icon;
import javax.swing.ImageIcon;
import javax.swing.JDesktopPane;
import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.KeyStroke;

import ys.com.internalFrame.SyssetInternalFrame;


public class MainFrm extends JFrame implements ActionListener{
    JDesktopPane desktop;
    
    //聲明系統主菜單
    static final String SYS="系統";
    static final String STORE="倉庫管理";
    static final String PURCHARCE="采購管理";
    static final String BANFANG="板房管理";
    
    //聲明系統子菜單項
    //1.系統子菜單項
    static final String SYS_SET="系統設置";
    static final String SYS_UMANAGER="用戶管理";
    static final String SYS_EXIT="退出系統";
    //2.倉庫子菜單項
    static final String STORE_BUBAN="布板管理";
    static final String STORE_IN="入庫管理";
    static final String STORE_OUT="出庫管理";
    static final String STORE_ORDER="物料訂購單";
    static final String STORE_RETURN="物料回貨單";
    
    public MainFrm() {
        super("YS_Main");
        int inset=50;
        Dimension screenSize=Toolkit.getDefaultToolkit().getScreenSize();
        setBounds(inset,inset,screenSize.width-inset*2,screenSize.height-inset*2);
        
        //創建圖形用戶界面
        desktop=new JDesktopPane();
        setContentPane(desktop);
        setJMenuBar(createMenuBar());
        
        //設置拖放效果
        desktop.setDragMode(JDesktopPane.OUTLINE_DRAG_MODE);
    }
    
    private static void createAndShowGUI() {
        javax.swing.JFrame.setDefaultLookAndFeelDecorated(true);
        MainFrm frame =new MainFrm();    //實例化主窗體界面
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setVisible(true);    //顯示窗體
    }
    public static void main(String[] args) {
        javax.swing.SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                createAndShowGUI();
            }
        });
    }
    
    //創建主菜單項方法createMenu()
    public JMenu createMenu(String name,int c,JMenuBar menuBar) {
        JMenu menu=new JMenu(name);
        menu.setMnemonic(c);
        menuBar.add(menu);
        return menu;
    }
    //創建子菜單項方法createMenuItem()
    public void createMenuItem(String name,int keyCode,JMenu menu,boolean sep) {
        JMenuItem menuItem=new JMenuItem(name);
        menuItem.setMnemonic(keyCode);
        menuItem.setAccelerator(KeyStroke.getKeyStroke(keyCode,ActionEvent.ALT_MASK));
        menuItem.setActionCommand(name);
        menuItem.addActionListener(this);
        menu.add(menuItem);
        if(sep)
        menu.addSeparator();//添加分割線
    }
    //定義創建菜單欄的方法createMenuBar()
    protected JMenuBar createMenuBar() {
        JMenuBar menuBar=new JMenuBar();    //定義菜單欄工具對象並實例化
        
        //添加菜單項,並初始化菜單項
        JMenu menuSYS=createMenu(SYS,KeyEvent.VK_S,menuBar);    
        JMenu menuSTORE=createMenu(STORE,KeyEvent.VK_C,menuBar);
        createMenu(PURCHARCE,KeyEvent.VK_P,menuBar);
        createMenu(BANFANG,KeyEvent.VK_B,menuBar);
        
        //添加子菜單項
        //1.實例化系統子菜單項
        createMenuItem(SYS_SET,KeyEvent.VK_0,menuSYS,false);
        createMenuItem(SYS_UMANAGER,KeyEvent.VK_1,menuSYS,false);
        createMenuItem(SYS_EXIT,KeyEvent.VK_X,menuSYS,false);
        //2.實例化倉庫管理子菜單項
        createMenuItem(STORE_BUBAN,KeyEvent.VK_B,menuSTORE,false);
        createMenuItem(STORE_IN,KeyEvent.VK_I,menuSTORE,false);
        createMenuItem(STORE_OUT,KeyEvent.VK_O,menuSTORE,true);
        createMenuItem(STORE_ORDER,KeyEvent.VK_D,menuSTORE,false);
        createMenuItem(STORE_RETURN,KeyEvent.VK_R,menuSTORE,false);

        return menuBar;
    }
    
    public void actionPerformed(ActionEvent e) {
        if(SYS_SET.equals(e.getActionCommand()))
            createSysSetFrame();
        if(SYS_EXIT.equals(e.getActionCommand()))
            quit();
    }
    
    protected void createSysSetFrame() {//打開用戶設置窗體
        SyssetInternalFrame frame = new SyssetInternalFrame();
        frame.setVisible(true); //necessary as of 1.3
        desktop.add(frame);
        try {
            frame.setSelected(true);
        } catch (java.beans.PropertyVetoException e) {}    
    }
    
    protected void quit() {
        System.exit(0);    //退出系統
    }
}

2.　建立一個帶有笑臉的簡單子窗體

package com.ys.internalFrame;

import java.awt.Container;

import javax.swing.JInternalFrame;

public class SyssetInternalFrame extends JInternalFrame {
    static int openFrameCount = 0;
    static final int xOffset = 30, yOffset = 30;
 
    public SyssetInternalFrame() {
        super("系統設置",// + (++openFrameCount), 
              true, //resizable
              true, //closable
              true, //maximizable
              true);//iconifiable
 
        //...Create the GUI and put it in the window...
        Container cp=getContentPane();
        FaceBean faceBean=new FaceBean();
        faceBean.setMouthWidth(60);
        faceBean.smile();
        //faceBean.frown();
        cp.add(faceBean);
        //...Then set the window size or call pack...
        setSize(500,300);
 
        //Set the window's location.
        setLocation(xOffset*openFrameCount, yOffset*openFrameCount);
    }

}

3.　定義笑臉控件類

package com.ys.entity;

import java.awt.*;
import javax.swing.*;
 
public class FaceBean extends JComponent {
    private int mMouthWidth = 90;    //初始化嘴巴默認寬度
    private boolean mSmile = true;    //默認情況顯示笑臉
     
    @Override
    public void paint(Graphics g) {
        Graphics2D g2 = (Graphics2D)g;
        g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
                RenderingHints.VALUE_ANTIALIAS_ON);
        // 臉
        int w = getWidth();
        int h = getHeight();
        int pad = 12;
        int cw = w - pad * 2;
        int ch = h - pad * 2;
        g2.setColor(getBackground());
        g2.fillArc(pad, pad, cw, ch, 0, 360);
        g2.setColor(getForeground());
        g2.drawArc(pad, pad, cw, ch, 0, 360);
        // 嘴
        int sw = cw / 2;
        int sh = ch / 2;
        if (mSmile == true)
            g2.drawArc(w / 2 - sw / 2, h / 2 - sh / 2, sw, sh, 270 - mMouthWidth / 2, mMouthWidth);
        else
            g2.drawArc(w / 2 - sw / 2, h / 2 + sh / 3, sw, sh, 90 - mMouthWidth / 2, mMouthWidth);
        // 眼睛
        int er = 4;
        g2.fillArc(w / 2 - cw * 1 / 8 - er / 2, h / 2 - ch / 4 - er, er, er, 0, 360);
        g2.fillArc(w / 2 + cw * 1 / 8 - er / 2, h / 2 - ch / 4 - er, er, er, 0, 360);
    }
     
    public int getMouthWidth() {
        return mMouthWidth;
    }
    
    //設置嘴巴寬度的方法
    public void setMouthWidth(int mw) {
        mMouthWidth = mw;
        repaint();
    }
    
    //顯示笑臉的方法
    public void smile() {
        mSmile = true;
        repaint();
    }
    
    //顯示苦臉的方法
    public void frown() {
        mSmile = false;
        repaint();
    }
}