文章目录

  • 一、组件和容器
  • 1、JFrame
  • 2、面板JPanel
  • 3、布局管理器
  • 流式布局（从左到右）
  • 东南西北中
  • 网格布局
  • 4、事件监听
  • 输入框事件监听
  • 键盘监听
  • 5、JDialog弹窗
  • 6、Icon、ImageIcon标签
  • Icon
  • ImageIcon
  • 7、按钮
  • 单选按钮
  • 复选按钮
  • 8、列表
  • 下拉框
  • 列表框
  • 9、文本框
  • 密码框
  • 文本域
  • 10、菜单
  • 关系图
  • 案例练习
  • 二、连接数据库
  • 总结

大家好，我是秋意临。

一、组件和容器

1、JFrame

package www.qyl.lesson01;

import javax.swing.*;
import java.awt.*;

public class TestFrame {
    public static void main(String[]args){
        JFrame frame = new JFrame("第一个GUI窗口");  
        frame.setSize(400,400);    //设置窗口大小
        frame.setLocation(200,200);  //弹出的初始位置
        frame.setBackground(new Color(49, 77, 125));  //设置背景颜色
        frame.setResizable(false); //设置大小固定（不可调整大小）
        frame.setVisible(true);  //设置窗口可见性
    }
}

gui界面java源代码 java gui编程_jvm

2、面板JPanel

注意： //JFrame设置背景色的区域一般是看不到的。一般看到的window背景区域是JFrame里的ContentPane，所以在ContentPane设置。

java frame.setBackground(new Color(52, 111, 121)); 改为 frame.getContentPane().setBackground(new Color(52, 111, 121)); 
package www.qyl.lesson01;

import javax.swing.*;
import java.awt.*;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;

public class TestPanel {
    public static void main(String[] args) {
        JFrame frame = new JFrame();   //创建窗体
        JPanel panel = new JPanel();    //创建面板
        frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);   //设置窗体可关闭
        frame.setLayout(null);          //定义布局为 绝对布局
        frame.setBounds(200,200,300,300);   //设置窗体x,y的坐标（弹出位置）和宽度、高度
        
        // frame.setBackground(new Color(52, 111, 121));    这样设置没有效果
        frame.getContentPane().setBackground(new Color(52, 111, 121)); //设置窗体背景颜色
        
        frame.setResizable(true);
        frame.setVisible(true);

        panel.setBackground(new Color(56, 127, 96));   //设置面板背景颜色
        panel.setBounds(50,50,180,150);
        frame.add(panel);   //将面板放入到窗体中
    }
}

gui界面java源代码 java gui编程_java_gui_02

3、布局管理器

流式布局（从左到右）

package www.qyl.lesson01;

import javax.swing.*;
import java.awt.*;

public class TestFlowLayout {
    public static void main(String[] args) {
        JFrame frame = new JFrame();
		
		//组件-按钮
        Button button1 = new Button("button1");
        Button button2 = new Button("button2");
        Button button3 = new Button("button3");

		//设置为流式布局
        frame.setLayout(new FlowLayout(FlowLayout.RIGHT));  //默认为从左到右，这里设置靠右边right
        frame.setSize(300,300);

        frame.add(button1);
        frame.add(button2);
        frame.add(button3);

        frame.setVisible(true);
    }
}

gui界面java源代码 java gui编程_开发语言_03

东南西北中

package www.qyl.lesson01;

import javax.swing.*;
import java.awt.*;

public class TestBorderLayout {
    public static void main(String[] args) {
        JFrame frame = new JFrame("TestBorderLayout");
        Button button1 = new Button("button1");
        Button button2 = new Button("button2");
        Button button3 = new Button("button3");
        Button button4 = new Button("button4");
        Button button5 = new Button("button5");
		
		//设置东南西北中布局
        frame.add(button1,BorderLayout.EAST);  
        frame.add(button2,BorderLayout.WEST);
        frame.add(button3,BorderLayout.SOUTH);
        frame.add(button4,BorderLayout.NORTH);
        frame.add(button5,BorderLayout.CENTER);

        frame.setSize(300,300);
        frame.setVisible(true);


    }
}

gui界面java源代码 java gui编程_gui界面java源代码_04

网格布局

package www.qyl.lesson01;

import javax.swing.*;
import java.awt.*;

public class TestGridLayout {
    public static void main(String[] args) {
        JFrame frame = new JFrame("TestBorderLayout");
        Button button1 = new Button("button1");
        Button button2 = new Button("button2");
        Button button3 = new Button("button3");
        Button button4 = new Button("button4");
        Button button5 = new Button("button5");
        Button button6 = new Button("button6");

		//设置网格布局，3行2列
        frame.setLayout(new GridLayout(3,2));

        frame.add(button1);
        frame.add(button2);
        frame.add(button3);
        frame.add(button4);
        frame.add(button5);
        frame.add(button6);

        frame.setSize(300,300);
        frame.setVisible(true);
    }
}

gui界面java源代码 java gui编程_java_05

4、事件监听

package www.qyl.lesson01;

import javax.swing.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

public class TestActionEvent {
    public static void main(String[] args) {
        JFrame jFrame = new JFrame();
        JButton button = new JButton("button1");
        jFrame.setBounds(10,10,300,300);
        jFrame.setVisible(true);
        jFrame.add(button);

        button.addActionListener(new MyActionEvent());
    }
}
class MyActionEvent implements ActionListener{

    @Override
    public void actionPerformed(ActionEvent e) {
        System.out.println("你点击了按钮！！");
    }
}

点击按钮后，就会触发System.out.println("你点击了按钮！！");这条命令

gui界面java源代码 java gui编程_gui界面java源代码_06


gui界面java源代码 java gui编程_jvm_07

输入框事件监听

package www.qyl.lesson01;

import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

public class TestActionEvent {
    public static void main(String[] args) {
        JFrame jFrame = new JFrame();
        jFrame.setBounds(10,10,300,300);
        jFrame.setVisible(true);
        JTextField jTextField = new JTextField("test:");
        jFrame.getContentPane().add(jTextField);
        jTextField.addActionListener(new MyActionEvent());
    }
}
class MyActionEvent implements ActionListener{

    @Override
    public void actionPerformed(ActionEvent e) {
        JTextField jTextField = (JTextField)e.getSource(); //获得一些资源、返回一个对象
        System.out.println(jTextField.getText());   //获得输入框中的内容
        jTextField.setText("");     //设置输入框为 null
    }
}

文本框输入文字回车后提交到后台

gui界面java源代码 java gui编程_java_08


gui界面java源代码 java gui编程_jvm_09

键盘监听

package www.qyl.lesson01;

import javax.swing.*;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;

public class TestKeyListener {
    public static void main(String[] args) {
        new KeyFrame();
    }
}

class KeyFrame extends JFrame{
    public KeyFrame(){
        setBounds(10,10,300,300);
        setVisible(true);

        this.addKeyListener(new KeyListener() {

            @Override
            public void keyTyped(KeyEvent e) {
                
            }

            @Override
            public void keyPressed(KeyEvent e) {

                int keycode = e.getKeyCode();  //获得键盘按下的哪一个键
                System.out.println(keycode);  //打印目前按下的键（会输出一个静态属性值）
                if (keycode == KeyEvent.VK_SPACE){   //键盘上每个健对应一个静态属性值：VK_XX
                    System.out.println("你按下了空格");
                }
            }

            @Override
            public void keyReleased(KeyEvent e) {

            }
        });
    }
}

gui界面java源代码 java gui编程_java_10

5、JDialog弹窗

package www.qyl.lesson01;

import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

public class TestDialog {
    public static void main(String[] args) {
        JFrame jFrame = new JFrame();
        jFrame.setVisible(true);
        jFrame.setBounds(10,10,300,300);
        JButton button = new JButton("button1");
        jFrame.getContentPane().add(button);
        button.addActionListener(new MyAction1());

    }
}
class MyAction1 implements ActionListener{

    @Override
    public void actionPerformed(ActionEvent e) {
        new MyDialogDemo();
    }
}

class MyDialogDemo {
    public MyDialogDemo(){
        JDialog jDialog = new JDialog();
        jDialog.setVisible(true);
        jDialog.setBounds(100,100,300,300);
    }
}

点击按钮弹出JDialog窗口

gui界面java源代码 java gui编程_java_gui_11

6、Icon、ImageIcon标签

Icon

package www.qyl.lesson02;

import javax.swing.*;
import java.awt.*;

public class IconDemo extends JFrame implements Icon {
    private int width,height;
    public IconDemo(){

    }
    public IconDemo(int width,int height){
        this.width = width;
        this.height = height;
    }
    public void init(){
        IconDemo iconDemo = new IconDemo(15,15);
        JLabel label = new JLabel("icontest",iconDemo,SwingConstants.CENTER);
        Container container = getContentPane();
        container.add(label);
        this.setBounds(50,50,100,100);
        this.setVisible(true);
        this.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
    }
    public static void main(String[] args) {
        new IconDemo().init();
    }

    @Override
    public void paintIcon(Component c, Graphics g, int x, int y) {
        g.fillOval(x,y,width,height);   //g:是画笔，g.fillOval画出一个图形
    }

    @Override
    public int getIconWidth() {
        return this.width;
    }

    @Override
    public int getIconHeight() {
        return this.height;
    }
}

gui界面java源代码 java gui编程_jvm_12

ImageIcon

图片也可以放在按钮上，称为图片按钮

package www.qyl.lesson02;

import com.sun.jndi.toolkit.url.UrlUtil;

import javax.swing.*;
import java.awt.*;
import java.net.URL;

public class ImageIconDemo extends JFrame {
    public ImageIconDemo(){

        JLabel label = new JLabel("ImageIcon");
        URL url = ImageIconDemo.class.getResource("hhy.png");  //获取本类路径下的图片路径，获取图片路径

        ImageIcon imageIcon = new ImageIcon(url);
        label.setIcon(imageIcon);
        Container container = getContentPane();
        container.add(label);

        setVisible(true);
        setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        setBounds(20,20,300,300);

    }
    public static void main(String[] args) {
        new ImageIconDemo();
    }
}

gui界面java源代码 java gui编程_jvm_13

7、按钮

单选按钮

package www.qyl.lesson02;

import javax.swing.*;

public class TestradioBttton {
    public static void main(String[] args) {
        JFrame jf = new JFrame();
        jf.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        jf.setBounds(10,10,300,300);
        jf.setVisible(true);
        JPanel jPanel = new JPanel();

jRadioButtonJiZhuPass.isSelected()

        JRadioButton jradio1 = new JRadioButton("男");
        JRadioButton jradio2 = new JRadioButton("女");
        //单选只能选择一个所以需要分组，一个组中只能选择一个
        ButtonGroup group = new ButtonGroup();
        group.add(jradio1);
        group.add(jradio2);
        
        //判断是否选中单选框
         System.out.println(jradio1.isSelected());  //返回Boolean类型
        
        jPanel.add(jradio1);
        jPanel.add(jradio2);

        jf.add(jPanel);
        
    }
}

gui界面java源代码 java gui编程_jvm_14

复选按钮

package www.qyl.lesson02;

import javax.swing.*;

public class TestradioBttton {
    public static void main(String[] args) {
        JFrame jf = new JFrame();
        jf.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        jf.setBounds(10,10,500,300);
        jf.setVisible(true);
        JPanel jPanel = new JPanel();

        JCheckBox jCheckBox1 = new JCheckBox("jCheckBox1");
        JCheckBox jCheckBox2 = new JCheckBox("jCheckBox2");
        JCheckBox jCheckBox3 = new JCheckBox("jCheckBox3");

        jPanel.add(jCheckBox1);
        jPanel.add(jCheckBox2);
        jPanel.add(jCheckBox3);
        jf.add(jPanel);

    }
}

gui界面java源代码 java gui编程_java_gui_15

8、列表

下拉框

package www.qyl.lesson02;

import javax.swing.*;
import java.awt.*;

public class TestradioBttton {
    public static void main(String[] args) {
        JFrame jf = new JFrame();
        jf.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        jf.setBounds(10,10,500,300);
        jf.setVisible(true);
        JPanel jPanel = new JPanel();
        JComboBox jComboBox = new JComboBox();
        jComboBox.addItem(null);
        jComboBox.addItem("1");
        jComboBox.addItem("2");
        jComboBox.addItem("3");
		
		System.out.println(jComboBox.getSelectedItem().toString().trim()); //获取下拉框选中的值
		
        jPanel.add(jComboBox);
        jf.add(jPanel);
    }
}

gui界面java源代码 java gui编程_开发语言_16

列表框

package www.qyl.lesson02;

import javax.swing.*;
import java.awt.*;

public class TestradioBttton {
    public static void main(String[] args) {
        JFrame jf = new JFrame();
        jf.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        jf.setBounds(10,10,500,300);
        jf.setVisible(true);
        JPanel jPanel = new JPanel();
        jPanel.setBounds(10,10,300,300);
        String[] con = {"1","2","3"};
        JList jList = new JList(con);
        
		
        jList.setBounds(10,10,100,100);
        jPanel.add(jList);
        jf.add(jPanel);
    }
}

gui界面java源代码 java gui编程_gui界面java源代码_17

9、文本框

package www.qyl.lesson02;

import javax.swing.*;
import java.awt.*;

public class TestradioBttton {
    public static void main(String[] args) {
        JFrame jf = new JFrame();
        jf.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        jf.setBounds(10,10,500,300);
        jf.setLayout(null);
        jf.setVisible(true);
        JPanel jPanel = new JPanel();
        jPanel.setBounds(10,10,300,300);

        JTextField jTextField = new JTextField("hello qyl");
        JTextField jTextField2 = new JTextField("hello 秋意临",20);

        jTextField.setBounds(10,10,60,30);
        jTextField2.setBounds(10,50,60,30);
        jPanel.add(jTextField);
        jPanel.add(jTextField2);
        jf.add(jPanel);
    }
}

gui界面java源代码 java gui编程_开发语言_18

密码框

package www.qyl.lesson02;

import javax.swing.*;
import java.awt.*;

public class TestradioBttton {
    public static void main(String[] args) {
        JFrame jf = new JFrame();
        jf.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        jf.setBounds(10,10,1000,300);
        jf.setLayout(null);
        jf.setVisible(true);
        JPanel jPanel = new JPanel();
        jPanel.setBounds(10,10,500,300);

        JPasswordField jPasswordField1 = new JPasswordField();
        jPasswordField1.setBounds(10,10,200,100);

        jPanel.add(jPasswordField1);

        jf.add(jPanel);
    }
}

gui界面java源代码 java gui编程_java_gui_19

文本域

package www.qyl.lesson02;

import javax.swing.*;
import java.awt.*;

public class TestradioBttton {
    public static void main(String[] args) {
        JFrame jf = new JFrame();
        jf.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        jf.setBounds(10,10,1000,300);
        jf.setLayout(null);
        jf.setVisible(true);
        JPanel jPanel = new JPanel();
        jPanel.setBounds(10,10,500,300);

        JTextArea jTextArea = new JTextArea(30,50);
        jTextArea.setText("hello秋意临：");

        jTextArea.setBounds(10,10,200,100);
        jPanel.add(jTextArea);
        jf.add(jPanel);
    }
}

gui界面java源代码 java gui编程_jvm_20

10、菜单

Java菜单提供JmenuBar，Jmenu，Jmenultem，JcheckboxMenultem类来创建和管理。

JcheckboxMenultem：复选框菜单项

关系图

gui界面java源代码 java gui编程_开发语言_21


gui界面java源代码 java gui编程_java_22

案例练习

gui界面java源代码 java gui编程_java_23

package www.qyl.lesson03;

import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

public class TestJMenuBar{
    public static void main(String[] args) {
        JFrame jf = new JFrame("菜单");
        Container container = jf.getContentPane();
        container.setLayout(null);
        jf.setBounds(10,10,300,300);
        jf.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        jf.setVisible(true);

        JMenuBar menuBar = new JMenuBar();          //创建菜单栏
        menuBar.setBounds(0,0,300,30);
        container.add(menuBar);    //菜单栏放入到JFrame顶层容器

        JMenu m1 = new JMenu("系统(n)");  // 设置一级菜单
        JMenu m2 = new JMenu("简介");
        JMenu m3 = new JMenu("工具");
        JMenu m4 = new JMenu("查询");
        JMenu m5 = new JMenu("关闭");

        m1.setMnemonic('n');  //设置快捷键

        menuBar.add(m1);   		//将一级菜单放入菜单栏中
        menuBar.add(m2);
        menuBar.add(m3);
        menuBar.add(m4);
        menuBar.add(m5);

        JMenu jmi1 = new JMenu("开始导航");  // 设置二级菜单项
        JMenu jmi2 = new JMenu("刷新系统");
        JMenu jmi3 = new JMenu("退出系统");

        m1.add(jmi1);			//将二级菜单项放入菜单中
        m1.addSeparator(); //分隔线
        m1.add(jmi2);
        m1.add(jmi3);

        JMenuItem jmi1_1 = new JMenuItem("硬件");  // 设置三级菜单项
        JMenuItem jmi1_2 = new JMenuItem("软件");
        JMenuItem jmi1_3 = new JMenuItem("杀毒");
        JMenuItem jmi1_4 = new JMenuItem("确认");
        JMenuItem jmi1_5 = new JMenuItem("取消");

        jmi1.add(jmi1_1);  		//将三级菜单项放入菜单中
        jmi1.addSeparator();  //分隔线
        jmi1.add(jmi1_2);
        jmi1.add(jmi1_3);
        
        JCheckBoxMenuItem jCheckBoxMenuItem1 = new JCheckBoxMenuItem("复选框菜单项"); //设置三级复选框
        jmi1.add(jCheckBoxMenuItem1);

        jmi3.add(jmi1_4);
        jmi3.add(jmi1_5);
        
        jmi1_4.addActionListener(new MyListener());  //点击确认退出程序
    }
}

class MyListener implements ActionListener {
    @Override
    public void actionPerformed(ActionEvent e) {
        System.exit(0);
    }
}

二、连接数据库

1、下载MySQL的驱动.jar包
下载地址：https://dev.mysql.com/downloads/connector/j/

gui界面java源代码 java gui编程_jvm_24

2、IDEA导入连接MySQL的驱动.jar包

gui界面java源代码 java gui编程_开发语言_25


3、连接数据库

package www.qyl.lesson03;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.*;

public class TestMysqlConnection {
    public static void main(String[] args)  {
        String url = "jdbc:mysql://127.0.0.1:3306/db_student";
        String user = "root";
        String pass = "000000";
        try {
//            Class.forName("com.mysql.jdbc.Driver");  //旧驱动程序类，不推荐
            Class.forName("com.mysql.cj.jdbc.Driver");  //驱动程序通过sql自动注册,驱动程序类
            Connection conn =  DriverManager.getConnection(url,user,pass);   //连接数据库

            Statement stmt = conn.createStatement();  //用于将sql语句发送到数据库中

            String sql = "select * from t_major";   
            ResultSet rs = stmt.executeQuery(sql);      //执行sql语句
            System.out.println(rs.next());          //结果为true
            while (rs.next()){
//                String name = rs.getString("major_name");  //通过字段检索
//                System.out.println(name);                 //输出查询字段
                System.out.println(rs.getInt(1) + "\t" + rs.getString(2));  //通过字段的索引检索
            }
            conn.close();
            rs.close();
            stmt.close();
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        } catch (SQLException throwables) {
            throwables.printStackTrace();
        }
    }
}