JAVASE——全面总结JAVA中的GUI编程

前言

万字深入总结JAVA中的swing编程

@[toc]

1.简介

• GUI的核心技术

  • Swing和AWT
  • 界面不美观
  • 需要jre环境！

• 可以写出自己心中想要的小工具

• 工作的时候，也可能需要维护到Swing界面，概率极小！

• 了解MVC架构，了解监听！

• 组件：

  • 窗口

  • 弹出

  • 面板

  • 文本框

  • 列表框

  • 按钮

  • 图片

  • 监听事件

  • 鼠标事件

  • 键盘事件

2、AWT

2.1、AWT介绍

1. new 类！
2. 包含了很多类和接口！
3. 用于GUI编程图像用户界面
4. 元素：窗口、按钮、文本框
5. java.awt包

2.2 、组件和容器

Frame

• 单窗口示例

public static void main(String[] args) {
    Frame frame = new Frame("我的第一个Java图形界面窗口");
	
    //设置窗口可见性
    frame.setVisible(true);
	
    //设置窗口大小
    frame.setSize(400,400);
	
    //设置窗口颜色
    frame.setBackground(Color.CYAN);

    //设置窗口的出现位置
    frame.setLocation(300,300);
	
    //是否可调整大小
    frame.setResizable(false);
}

• 多窗口示例

public class OneFrame {
    public static void main(String[] args) {
        MyFrame l1 = new MyFrame(100, 100, 200, 200, Color.yellow);
        MyFrame l2 = new MyFrame(300, 100, 200, 200, Color.CYAN);
        MyFrame l3 = new MyFrame(100, 300, 200, 200, Color.black);
        MyFrame l4 = new MyFrame(300, 300, 200, 200, Color.blue);
    }
}

class MyFrame extends Frame {

    static int n = 0;
    public MyFrame(int x, int y, int w, int h, Color color) {
        super("l" + (n++));
        setVisible(true);
        setBounds(x, y, w, h);
        setBackground(color);
        setResizable(false);
    }
}

面板Panel（解决关闭问题）

public static void main(String[] args) {
    Frame frame = new Frame();
    Panel panel = new Panel();

    //设置布局
    frame.setLayout(null);

    //坐标
    frame.setBounds(100,100,100,100);
    frame.setBackground(new Color(40,40,40));

    //panel设置坐标，相对于frame
    panel.setBounds(50,50,50,50);
    panel.setBackground(new Color(199,199,199));

    frame.add(panel);

    frame.setVisible(true);

    //监听事件，监听创口关闭事件,System.exit(0)；适配器模式
    frame.addWindowListener(new WindowAdapter() {
        //窗口点击关闭的时候需要做的事情
        public void windowClosing(WindowEvent e) {
            System.exit(0);
        }
    });
}

布局管理器

• 流式布局

public static void main(String[] args) {
        Frame frame = new Frame("FlowLayout");

        //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());//默认居中
        frame.setLayout(new FlowLayout(FlowLayout.LEFT));//左
        frame.setLayout(new FlowLayout(FlowLayout.RIGHT));//右

        frame.setSize(400,400);

        //把按钮添加上去
        frame.add(button1);
        frame.add(button2);
        frame.add(button3);

        frame.setVisible(true);
}

• 东西南北中布局

public static void main(String[] args) {
        Frame frame = new Frame("BorderLayout");
        
    	Button east = new Button("East");
        Button west = new Button("West");
        Button south = new Button("South");
        Button north = new Button("North");
        Button center = new Button("Center");
        
    	frame.add(east,BorderLayout.EAST);
        frame.add(west,BorderLayout.WEST);
        frame.add(south,BorderLayout.SOUTH);
        frame.add(north,BorderLayout.NORTH);
        frame.add(center,BorderLayout.CENTER);

        //自动选择
        frame.pack();
        frame.setVisible(true);
}

• 表格布局

public static void main(String[] args) {
        Frame frame = new Frame("GridLayout");
        
    	Button btn1 = new Button("btn1");
        Button btn2 = new Button("btn2");
        Button btn3 = new Button("btn3");
        Button btn4 = new Button("btn4");
        Button btn5 = new Button("btn5");
        Button btn6 = new Button("btn6");

        frame.setLayout(new GridLayout(3,2));

        frame.add(btn1);
        frame.add(btn2);
        frame.add(btn3);
        frame.add(btn4);
        frame.add(btn5);
        frame.add(btn6);

        frame.pack();//Java函数！ 自动选择一个最优的位置来确定
        frame.setVisible(true);
    }

• 多种布局结合：

public static void main(String[] args) {
        Frame frame = new Frame();
        frame.setVisible(true);
        frame.setBackground(Color.WHITE);
        frame.setBounds(600,600,200,200);
        frame.setLayout(new GridLayout(2,1));

        Panel panel1 = new Panel(new BorderLayout());
        Panel panel2 = new Panel(new GridLayout(2,1));
        Panel panel3 = new Panel(new BorderLayout());
        Panel panel4= new Panel(new GridLayout(2,2));

        panel1.add(new Button("East"),BorderLayout.EAST);
        panel1.add(new Button("West"),BorderLayout.WEST);
        panel2.add(new Button("panel2"));
        panel2.add(new Button("panel2"));
        panel1.add(panel2,BorderLayout.CENTER);

        panel3.add(new Button("East"),BorderLayout.EAST);
        panel3.add(new Button("West"),BorderLayout.WEST);
        for(int i=0;i<4;i++){
            panel4.add(new Button("panel4"));
        }
        panel3.add(panel4,BorderLayout.CENTER);

        frame.add(panel1);
        frame.add(panel3);

        frame.addWindowListener(new WindowAdapter() {
            @Override
            public void windowClosing(WindowEvent e) {
                System.exit(0);
            }
        });
    }

• 总结：

  • Frame是一个顶级窗口
  • Panel 无法单独显示，必须添加到某个容器中
  • 布局管理器
    • 流式布局
    • 东西南北中布局
    • 表格式布局

事件监听

    public static void main(String[] args) {
        //按下按钮，触发一些事件
        Frame frame = new Frame();
        Button button = new Button();

        //因为addActionListener()需要addActionListener 所以我们需要构造一个addActionListener
        MyActionListener myActionListener = new MyActionListener();
        button.addActionListener(myActionListener);

        frame.add(button, BorderLayout.CENTER);
        frame.pack();
        frame.setVisible(true);

        WindownClose(frame);//调用关闭窗口
    }

    //关闭窗口事件
    private static void WindownClose(Frame frame) {
        frame.addWindowListener(new WindowAdapter() {
            @Override
            public void windowClosing(WindowEvent e) {
                System.exit(0);
            }
        });
    }

    //事件监听
    class MyActionListener implements ActionListener {
        @Override
        public void actionPerformed(ActionEvent e) {
            System.out.println("66666！");
        }
    }

多个按钮共享一个事件

	 public static void main(String[] args) {
        //两个按钮实现同一个监听

        //开始----停止
        Frame frame = new Frame("开始-停止");
        Button button1 = new Button("start");
        Button button2 = new Button("stop");
        
        //可以显示的定义触发会返回命令，如果不显示定义，则会走默认的值
        //可以多个按钮只写一个监听类
        button2.setActionCommand("stop");
       
        MyMonitor myMonitor = new MyMonitor();

        button1.addActionListener(myMonitor);
        button2.addActionListener(myMonitor);

        frame.add(button1,BorderLayout.NORTH);
        frame.add(button2,BorderLayout.SOUTH);

        frame.pack();
        frame.setVisible(true);
    }

    class  MyMonitor implements ActionListener{
        @Override
        public void actionPerformed(ActionEvent e) {
            //e.getActionCommand()获取按钮上的信息
            System.out.println("按钮被点击了：msg=>"+ e.getActionCommand());
            if(e.getActionCommand().equals("start")){

            }
        }
    }

输入框TextField监听

	public static void main(String[] args) {
        //main里只管启动
        new MyFrame2();
    }

	class MyFrame2 extends Frame{
        public MyFrame2(){
            TextField textField = new TextField();
            //因为extends Frame 所有Frame可以不用写
            
            add(textField);
            
            //监听这个文本框输入的文字
            MyActionListener2 myActionListener2 = new MyActionListener2();
            
            //按钮下回车就会触发这个输入框的事件
            textField.addActionListener(myActionListener2);
            
            //设置编码
            textField.setEchoChar('*');//密码框
            setVisible(true);
            pack();
        }
	}

    class MyActionListener2 implements ActionListener{
        @Override
        public void actionPerformed(ActionEvent e) {
          TextField field=(TextField)e.getSource();//获得一些资源,返回一个对象
            System.out.println(field.getText());//获得输入框文本
            field.setText"");  //不能NULL
        }
    }

简易计算器

• 面向过程

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

    //计算器类
    class  Calculator extends Frame{
        public Calculator()  {
            
            //3个文本框
            TextField num1 = new TextField(10);//字符数
            TextField num2 = new TextField(10);//字符数
            TextField num3= new TextField(20);//字符数
            
            //1个按钮
            Button button = new Button("=");
            
            //监听
            button.addActionListener(new MyCalculatorListener(num1,num2,num3 ));
            
            //1个标签
            Label label = new Label("+");
            
            //布局
            setLayout(new FlowLayout());
            add(num1);
            add(label);
            add(num2);
            add(button);
            add(num3);
            pack();
            setVisible(true);
        }
    }

    //监听器类
    class  MyCalculatorListener implements ActionListener{
        
        //获取三个变量
        private TextField num1,num2,num3;//需要在这也写这个
        public MyCalculatorListener( TextField num1, TextField num2, TextField num3){
            this.num1 = num1;
            this.num2 = num2;
            this.num3 = num3;
        }
        public void actionPerformed(ActionEvent e) {

            //1.获得加数和被加数
            int n1 =  Integer.parseInt(num1.getText());//将字符串类型转换为int类型
            int n2 =  Integer.parseInt(num2.getText());
            
            //2.将这个值加法运算后放入第三个框中
            num3.setText(""+(n1+n2));

            //3.清除前两个框的内容
            num1.setText("");
            num2.setText("");
        }
    }

• 面向对象

    public static void main(String[] args) {
            
        new Calculator().loadFrame();
    }

    //计算器类
    class  Calculator extends Frame{
        
        //属性
        TextField num1,num2,num3;
        
        //方法
        public  void  loadFrame(){
            
            num1 = new TextField(10);
            num2 = new TextField(10);
            num3= new TextField(20);
            Button button = new Button("=");
            Label label = new Label("+");
            button.addActionListener(new MyCalculatorListener(this));
            setLayout(new FlowLayout());
            add(num1);
            add(label);
            add(num2);
            add(button);
            add(num3);
            pack();
            setVisible(true);
        }
    }

    //监听器类
    class  MyCalculatorListener implements ActionListener{
        
        //获取计算器这个对象，在一个类中组合另外一个类
        Calculator calculator=null;
        public MyCalculatorListener(Calculator calculator){
            
            this.calculator=calculator;
        }
        @Override
        public void actionPerformed(ActionEvent e) {
            
            //1.获得加数和被加数
            int n1=Integer.parseInt(calculator.num1.getText());
            int n2=Integer.parseInt(calculator.num2.getText());
            
            //2.将这个值加法运算后放入第三个框中
            calculator.num3.setText(""+(n1+n2));
            
            //3.清除前两个框的内容
            calculator.num1.setText("");
            calculator.num2.setText("");
        }
    }

• 内部类：更好的包装

    public static void main(String[] args) {
            
        new Calculator().loadFrame();
	 }
    
	//计算器类
    class  Calculator extends Frame{
       
        //属性
        TextField num1,num2,num3;
        
        //方法
        public  void  loadFrame(){
            num1 = new TextField(10);
            num2 = new TextField(10);
            num3= new TextField(20);
            Button button = new Button("=");
            Label label = new Label("+");
            button.addActionListener(new MyCalculatorListener());
            setLayout(new FlowLayout());
            add(num1);
            add(label);
            add(num2);
            add(button);
            add(num3);
            pack();
            setVisible(true);
        }
        
        //监听器类
        //内部类最大的好处就是可以畅通无阻的访问外部的属性和方法
        private  class  MyCalculatorListener implements ActionListener{
            @Override
            public void actionPerformed(ActionEvent e) {
                
                //1.获得加数和被加数
                int n1=Integer.parseInt(num1.getText());
                int n2=Integer.parseInt(num2.getText());
                
                //2.将这个值加法运算后放入第三个框中
                num3.setText(""+(n1+n2));
                
                //3.清除前两个框的内容
                num1.setText("");
                num2.setText("");
            }
        }
    }

画笔

    public static void main(String[] args) {
            new MyPaint().loadFrame();
    }

    class MyPaint extends Frame{
        public void loadFrame(){
            setBounds(200,200,600,400);
            setVisible(true);
        }
        
        //画笔
        @Override
        public void paint(Graphics g) {
           
            //画笔，需要有颜色，可以画画
            g.setColor(Color.red);
            g.drawOval(100,100,100,100);
            g.fillOval(100,100,100,100);//实心圆
           
            g.setColor(Color.green);
            g.fillRect(150,150,100,100);//四边形

            //画笔用完，还原到最初的颜色
        }
    }

鼠标监听

    public static void main(String[] args) {
            new MyFrame("画图");
    }

    class  MyFrame extends Frame {

        //画画需要画笔，需要监听鼠标当前的位置，需要集合来存储画出来的东西
        ArrayList points;
        public MyFrame(String title) {
            super(title);
            setBounds(200, 200, 400, 400);

            //存储鼠标点击的点
            points = new ArrayList<>();
            setVisible(true);

            //鼠标监听器，针对窗口
            this.addMouseListener(new MyMouseListener());
        }

        //画画需要重写画笔
        @Override
        public void paint(Graphics g) {

            //画画、需要监听鼠标事件
            Iterator iterator = points.iterator();
            while (iterator.hasNext()) {
                Point point = (Point) iterator.next();
                g.setColor(Color.red);
                g.fillOval(point.x, point.y, 10, 10);
            }
        }
        //添加点到界面上
        public  void addPaint(Point point){

            points.add(point);
        }


        //适配器模式
        private class MyMouseListener extends MouseAdapter {

            //鼠标按下 弹起  按住不放
            public void mousePressed(MouseEvent e) {
                MyFrame frame = (MyFrame) e.getSource();

                //这里我们点击的时候，就会在界面上产生一个点-->画
                frame.addPaint(new Point(e.getX(), e.getY()));
                //这个点就是鼠标的点

                //每次点击鼠标 都需要重写画一遍
                frame.repaint();//刷新
            }
        }
    }

窗口监听

	//鼠标监听事件
    public static void main(String[] args) {
        new WindowFrame();

    }

    class WindowFrame extends Frame {
        public WindowFrame() {
            setBounds(100, 100, 200, 200);
            setBackground(Color.GREEN);
            setVisible(true);
            //addWindowListener(new MyWindownListener());
            this.addWindowListener(

                    //匿名内部类
                    new WindowAdapter() {
                        @Override
                        public void windowOpened(WindowEvent e) {
                            System.out.println("windowOpened");
                        }

                        //关闭窗口
                        @Override
                        public void windowClosing(WindowEvent e) {
                            System.out.println("windowClosing");
                            System.exit(0);
                        }

                        @Override
                        public void windowClosed(WindowEvent e) {
                            System.out.println("windowClosed");
                        }

                        //激活窗口
                        @Override
                        public void windowActivated(WindowEvent e) {
                            WindowFrame source = (WindowFrame) e.getSource();
                            source.setTitle("被激活了");
                            System.out.println("windowActivated");
                        }

                    }
            );
        }
    }

键盘监听

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

    class KeyFrame extends Frame{
        public KeyFrame() {
            setBounds(1, 2, 300, 400);
            setVisible(true);
            this.addKeyListener(new KeyAdapter() {
                
                //键盘按下
                @Override
                public void keyPressed(KeyEvent e) {
                    
                    //键盘按下的键是哪一个
                    int keyCode = e.getKeyCode();//获取当前键盘的码
                    System.out.println(keyCode);  //不需要记住，直接使用VK_XXX
                    if (keyCode==KeyEvent.VK_UP){
                        System.out.println("你按下了上键");
                    }
                    //根据按下的键，产生不同的结果
                }
            });
        }
    }

3、Swing

3.1、窗口

    public static void main(String[] args) {
            new MyJFrame2().init();
        }

    class MyJFrame2 extends JFrame{
        public void  init(){
            this.setBounds(100,100,200,200);
            this.setVisible(true);
            JLabel label = new JLabel("欢迎学习Java");
            this.add(label);
            
            //让文本标签居中  设置水平对齐
            label.setHorizontalAlignment(SwingConstants.CENTER);
            
            //获得一个容器
            Container content = this.getContentPane();
            content.setBackground(Color.cyan);
        }
    }

3.2、弹窗

• JDialog，用来被弹出，默认就有关闭窗口事件

public class DialogDemo extends JFrame{
	public DialogDemo() {
        
        this.setVisible(true);
        this.setSize(700,500);
        this.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);

        //JFrame 放东西---需要容器
        Container container = this.getContentPane();
        
        //绝对布局
        container.setLayout(null);

        //按钮
        JButton button = new JButton("点击弹出对话框");
        button.setBounds(30,30,200,50);

        //点击这个按钮的时候，弹出一个弹窗（监听）
        button.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                
                //弹窗
                new MyDailogDemo();
            }
        });
        container.add(button);
    }

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

//弹窗的窗口
class MyDailogDemo extends JDialog{
    public MyDailogDemo() {
        this.setVisible(true);
        this.setBounds(100,100,500,500);
        //this.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE); 默认已有这个功能

        Container container = this.getContentPane();
        
        //设置为决定定位
        container.setLayout(null);
        container.add(new Label("欢迎学习Java！"));
    }
}

3.3、标签

public class ImageIconDemo extends JFrame {
    public ImageIconDemo(){
        
        //获取图片地址
        JLabel label = new JLabel("ImageIcon");
        URL url = ImageIconDemo.class.getResource("tx.png");
        ImageIcon imageIcon = new ImageIcon(url);//命名不要重复
        label.setIcon(imageIcon);
        label.setHorizontalAlignment(SwingConstants.CENTER);

        Container container = getContentPane();
        container.add(label);
        setVisible(true);
        setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        setBounds(100,100,200,200);
    }

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

3.4、面板

• JPanel

public class JPanelDemo extends JFrame {
    public JPanelDemo(){
        
        //所有的东西放在container里边
        Container container = this.getContentPane();
        container.setLayout(new GridLayout(2,1,10,10));//后面参数的意思是间距

        JPanel panel1 = new JPanel(new GridLayout(1,3));
        JPanel panel2 = new JPanel(new GridLayout(1,2));
        JPanel panel3 = new JPanel(new GridLayout(2,1));
        JPanel panel4 = new JPanel(new GridLayout(3,2));

        panel1.add(new JButton("1"));
        panel1.add(new JButton("1"));
        panel1.add(new JButton("1"));
        panel2.add(new JButton("2"));
        panel2.add(new JButton("2"));
        panel3.add(new JButton("3"));
        panel3.add(new JButton("3"));
        panel4.add(new JButton("4"));
        panel4.add(new JButton("4"));
        panel4.add(new JButton("4"));
        panel4.add(new JButton("4"));
        panel4.add(new JButton("4"));
        panel4.add(new JButton("4"));
        container.add(panel1);
        container.add(panel2);
        container.add(panel3);
        container.add(panel4);

        this.setVisible(true);
        this.setSize(500,500);
        this.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
    }
    
    public static void main(String[] args) {
        new JPanelDemo();
    }
}

• JScrollPanel:

public class JScrollDemo extends JFrame {
    public JScrollDemo(){
        Container container = this.getContentPane();

        //文本域
        JTextArea textArea=new JTextArea(20,20);
        textArea.setText("欢迎学习Java");
        //Scroll面板
        JScrollPane scrollPane = new JScrollPane(textArea);
        container.add(scrollPane);

         this.setVisible(true);
         this.setBounds(100,100,300,350);
         this.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
    }

    public static void main(String[] args) {

        new JScrollDemo();
    }
}

3.5、按钮

• 图片按钮

public class JButtonDemo extends JFrame {
    public JButtonDemo(){
        Container container = this.getContentPane();
        //将一个图片变为图标
        URL resource = JButtonDemo.class.getResource("tx.png");
        Icon icon = new ImageIcon(resource);

        //把这个图片放在按钮上
        JButton button = new JButton();
        button.setIcon(icon);
        button.setToolTipText("图片按钮");

        //add
        container.add(button);

        this.setVisible(true);
        this.setSize(500,300);
        this.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
    }

    public static void main(String[] args) {

        new JButtonDemo();
    }
}

• 单选按钮

public class JButtonDemo02 extends JFrame {
    public JButtonDemo02(){
        Container container = this.getContentPane();
        //将一个图片变为图标
        URL resource = JButtonDemo.class.getResource("tx.png");
        Icon icon = new ImageIcon(resource);

        //单选框
        JRadioButton radiobutton01 = new JRadioButton("单选框1");
        JRadioButton radiobutton02 = new JRadioButton("单选框2");
        JRadioButton radiobutton03 = new JRadioButton("单选框3");
        //由于单选框只能选择一个，需要分组---一个组中只能选择一个
        ButtonGroup ground = new ButtonGroup();
        ground.add(radiobutton01);
        ground.add(radiobutton02);
        ground.add(radiobutton03);

        container.add(radiobutton01,BorderLayout.CENTER);
        container.add(radiobutton02,BorderLayout.NORTH);
        container.add(radiobutton03,BorderLayout.SOUTH);

        this.setVisible(true);
        this.setSize(500,300);
        this.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        
    }

    public static void main(String[] args) {

        new JButtonDemo02();
    }
}

• 复选按钮

public class JButtonDemo03 extends JFrame {
    public JButtonDemo03(){
        Container container = this.getContentPane();
        //将一个图片变为图标
        URL resource = JButtonDemo.class.getResource("tx.png");
        Icon icon = new ImageIcon(resource);

        //多选框
        JCheckBox checkBox01 = new JCheckBox(" checkBox01");
        JCheckBox checkBox02 = new JCheckBox(" checkBox02");

        container.add(checkBox01,BorderLayout.NORTH);
        container.add(checkBox02,BorderLayout.SOUTH);

        this.setVisible(true);
        this.setSize(500,300);
        this.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);

    }

    public static void main(String[] args) {

        new JButtonDemo03();
    }
}

3.6、列表

• 下拉框

public class TestComboboxDemo01 extends JFrame {
    public TestComboboxDemo01(){
        Container container = this.getContentPane();

        JComboBox status = new JComboBox<>();
        status.addItem(null);
        status.addItem("正在热映");
        status.addItem("已下架");
        status.addItem("即将上映");

        container.add(status);

        this.setVisible(true);
        this.setSize(500,350);
        this.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);

    }

    public static void main(String[] args) {
           new TestComboboxDemo01();
    }
}

• 列表框

public class TestComboboxDemo02 extends JFrame {
    public TestComboboxDemo02() {
        Container container = this.getContentPane();

        //生成列表内容
       //String[] contents={"1","2","3"};

        Vector contents = new Vector();
        //列表中需要放入内容
        JList jList = new JList(contents);

        contents.add("1");
        contents.add("2");
        contents.add("3");

        container.add(jList);

        this.setVisible(true);
        this.setSize(500,300);
        this.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);

    }

    public static void main(String[] args) {
        new TestComboboxDemo02();
    }
}

• 应用场景：
  • 选择地区或者一些单个选项
  • 列表，展示信息，一般是动态内容

3.7、文本框

• 文本框

public class TestTextDemo01  extends JFrame {
    public  TestTextDemo01 (){
        Container container = this.getContentPane();
        //container.setLayout(null);//绝对布局

        JTextField textField = new JTextField("hellow");
        JTextField textField2 = new JTextField("world",20);

        container.add(textField,BorderLayout.NORTH);
        container.add(textField2,BorderLayout.SOUTH);

        this.setVisible(true);
        this.setSize(500,350);
        this.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);

    }

    public static void main(String[] args) {
        new  TestTextDemo01 ();
    }
}

• 密码框

public class TestTextDemo02  extends JFrame {
    public  TestTextDemo02 (){
        Container container = this.getContentPane();

        //密码框
        JPasswordField passwordField = new JPasswordField();//****
        passwordField.setEchoChar('*');

        container.add(passwordField);

        this.setVisible(true);
        this.setSize(500,350);
        this.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);

    }

    public static void main(String[] args) {
        new  TestTextDemo02 ();
    }
}

• 文本域

public class JScrollDemo extends JFrame {
    public JScrollDemo(){
        Container container = this.getContentPane();

        //文本域
        JTextArea textArea=new JTextArea(20,20);
        textArea.setText("欢迎学习Java");
        //Scroll面板
        JScrollPane scrollPane = new JScrollPane(textArea);
        container.add(scrollPane);

         this.setVisible(true);
         this.setBounds(100,100,300,350);
         this.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);

    }

    public static void main(String[] args) {

        new JScrollDemo();
    }
}