17.文本域、JScroll面板

JPanel面板：重点，布局有间距

package com.gui.lesson4;

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

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

        container.setLayout(new GridLayout(2, 1, 10, 10));//后面两个参数的意思，间距

        JPanel jPanel = new JPanel(new GridLayout(1, 3));
        JPanel jPane2 = new JPanel(new GridLayout(1, 2));
        JPanel jPane3 = new JPanel(new GridLayout(2, 1));
        JPanel jPane4 = new JPanel(new GridLayout(3, 2));

        jPanel.add(new JButton("1"));
        jPanel.add(new JButton("1"));
        jPanel.add(new JButton("1"));
        jPane2.add(new JButton("2"));
        jPane2.add(new JButton("2"));
        jPane3.add(new JButton("3"));
        jPane3.add(new JButton("3"));
        jPane4.add(new JButton("4"));
        jPane4.add(new JButton("4"));
        jPane4.add(new JButton("4"));
        jPane4.add(new JButton("4"));
        jPane4.add(new JButton("4"));
        jPane4.add(new JButton("4"));

        container.add(jPanel);
        container.add(jPane2);
        container.add(jPane3);
        container.add(jPane4);

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

    }

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

文本域，JScrollPanel面板：滚动

package com.gui.lesson4;

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

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

        //文本域
        JTextArea textArea = new JTextArea(20, 50);
        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, 150);
        setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
    }

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