Java：实现一个能够改变显示单词的字体风格和大小的GUI【V2】（第十四周）

野性酷女 2022-05-15 04:45 108阅读 0赞

题目来源：大工慕课 [链接][Link 1]  
作者：Caleb Sung

# 题目要求 #

Implement a GUI as shown in the following figure:  
![这里写图片描述][70]  
Input Menu:  
![这里写图片描述][70 1]  
![这里写图片描述][70 2]  
![这里写图片描述][70 3]  
Edit Menu:  
![这里写图片描述][70 4]  
![这里写图片描述][70 5]  
Tool Bar:  
![这里写图片描述][70 6]

--------------------

# 参考解答 #

import java.awt.BorderLayout;
    import java.awt.Color;
    import java.awt.Dimension;
    import java.awt.Font;
    import java.awt.Toolkit;
    import javax.swing.ButtonGroup;
    import javax.swing.ImageIcon;
    import javax.swing.JButton;
    import javax.swing.JCheckBoxMenuItem;
    import javax.swing.JFrame;
    import javax.swing.JLabel;
    import javax.swing.JMenu;
    import javax.swing.JMenuBar;
    import javax.swing.JMenuItem;
    import javax.swing.JOptionPane;
    import javax.swing.JRadioButtonMenuItem;
    import javax.swing.JToolBar;
    
    public class TestFontGUI {
        public static void main(String[] args) {
            new FontGUI();
        }
    }
    
    @SuppressWarnings("serial")
    class FontGUI extends JFrame {
    
        int fontSize;
        JLabel label = new JLabel("The quick brown fox jumps over the lazy dog.");
        JRadioButtonMenuItem largeItem = new JRadioButtonMenuItem("Large");
        JRadioButtonMenuItem mediumItem = new JRadioButtonMenuItem("Medium");
        JRadioButtonMenuItem smallItem = new JRadioButtonMenuItem("Small");
        JCheckBoxMenuItem boldItem = new JCheckBoxMenuItem("Bold");
        JCheckBoxMenuItem italicItem = new JCheckBoxMenuItem("Italic");
        Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
        String input;
    
        public FontGUI() {
    
            setTitle("Menu Test Frame");
            setVisible(true);
            setDefaultCloseOperation(EXIT_ON_CLOSE);
    
            label.setFont(new Font("Serif", Font.PLAIN, 25));
            add(label, BorderLayout.CENTER);
    
            JMenuBar mb = new JMenuBar();
            setJMenuBar(mb);
    
            JMenu inputMenu = new JMenu("Input");
            mb.add(inputMenu);
    
            JMenuItem newItem = new JMenuItem("New");
            inputMenu.add(newItem);
    
            newItem.addActionListener(e -> {
                input = JOptionPane.showInputDialog("Type here:");
                if (input == null) {
                    JOptionPane.showConfirmDialog(null, "You must input something in this textbox!", "Attention",
                            JOptionPane.DEFAULT_OPTION);
                    input = "The quick brown fox jumps over the lazy dog.";
                } else if (input.length() <= 4) {
                    JOptionPane.showConfirmDialog(null, "The length of your input should be longer than 4 charactors!",
                            "Attention", JOptionPane.DEFAULT_OPTION);
                    input = "The quick brown fox jumps over the lazy dog.";
                } else
                    label.setText(input);
                pack();
                setLocation(screenSize.width / 2 - getSize().width / 2, screenSize.height / 2 - getSize().height / 2);
            });
    
            JToolBar tb = new JToolBar();
            JButton redButton = new JButton(new ImageIcon("red-ball.gif"));
            tb.add(redButton);
            JButton greenButton = new JButton(new ImageIcon("green-ball.gif"));
            tb.add(greenButton);
            JButton blueButton = new JButton(new ImageIcon("blue-ball.gif"));
            tb.add(blueButton);
            add(tb, BorderLayout.NORTH);
    
            redButton.addActionListener(e -> label.setForeground(Color.RED));
            greenButton.addActionListener(e -> label.setForeground(Color.GREEN));
            blueButton.addActionListener(e -> label.setForeground(Color.BLUE));
    
            JMenu editMenu = new JMenu("Edit");
            mb.add(editMenu);
    
            JMenu colorMenu = new JMenu("Color");
            editMenu.add(colorMenu);
    
            JMenuItem redItem = new JMenuItem("Red");
            JMenuItem greenItem = new JMenuItem("Green");
            JMenuItem blueItem = new JMenuItem("Blue");
    
            colorMenu.add(redItem);
            colorMenu.add(greenItem);
            colorMenu.add(blueItem);
    
            redItem.addActionListener(e -> label.setForeground(Color.RED));
            greenItem.addActionListener(e -> label.setForeground(Color.GREEN));
            blueItem.addActionListener(e -> label.setForeground(Color.BLUE));
    
            JMenu fontMenu = new JMenu("Font");
            editMenu.add(fontMenu);
    
            fontMenu.add(boldItem);
            fontMenu.add(italicItem);
    
            ButtonGroup bg = new ButtonGroup();
            bg.add(smallItem);
            bg.add(mediumItem);
            bg.add(largeItem);
            fontMenu.add(smallItem);
            fontMenu.add(mediumItem);
            fontMenu.add(largeItem);
    
            smallItem.setSelected(true);
    
            boldItem.addActionListener(e -> {
                changeFont();
            });
            italicItem.addActionListener(e -> {
                changeFont();
            });
            smallItem.addActionListener(e -> {
                changeFont();
            });
            mediumItem.addActionListener(e -> {
                changeFont();
            });
            largeItem.addActionListener(e -> {
                changeFont();
            });
    
            pack();
            setLocation(screenSize.width / 2 - getSize().width / 2, screenSize.height / 2 - getSize().height / 2);
        }
    
        void changeFont() {
            int mode = Font.PLAIN;
            if (boldItem.isSelected())
                mode += Font.BOLD;
            if (italicItem.isSelected())
                mode += Font.ITALIC;
            if (smallItem.isSelected())
                fontSize = 25;
            else if (mediumItem.isSelected())
                fontSize = 40;
            else if (largeItem.isSelected())
                fontSize = 60;
            label.setFont(new Font("Serif", mode, fontSize));
            pack();
            validate();
            setLocation(screenSize.width / 2 - getSize().width / 2, screenSize.height / 2 - getSize().height / 2);
        }
    }

[Link 1]: https://mooc.dlut.edu.cn/
[70]: /images/20220515/448525053baf40bfad0819cb71aa492d.png
[70 1]: /images/20220515/c71d7c6a4e15442fa4aa21df6bae27ec.png
[70 2]: /images/20220515/aae6dd014a4d42b9b3bf3a609715e2a2.png
[70 3]: /images/20220515/8b5e4fde47804974af85ffae6ca7ae7e.png
[70 4]: /images/20220515/b9b0aab582c24234a57f00ddc8aa54c4.png
[70 5]: /images/20220515/767c62618c6c48fda80b5da02219d4ad.png
[70 6]: /images/20220515/5a047bbd7f2c4ef5b98b3469561bd30e.png