《Java課程實習》日誌（周三）

package xuexi;import java.awt.EventQueue;import javax.imageio.ImageIO;import javax.swing.JFrame;import javax.swing.JPanel;import javax.swing.border.EmptyBorder;import javax.swing.ImageIcon;import javax.swing.JButton;import javax.swing.JFileChooser;import javax.swing.JTextField;import javax.swing.JLabel;import java.awt.Color;import java.awt.Image;import java.awt.SystemColor;import java.awt.event.ActionListener;import java.awt.event.ActionEvent;import java.awt.event.MouseAdapter;import java.awt.event.MouseEvent;import java.io.File;import java.io.FileFilter;import java.io.IOException;@SuppressWarnings("unused")public class Guess01 extends JFrame {    /**     *      */    private static final long serialVersionUID = 1L;        private JPanel contentPane;    private JTextField tfDir;    private JTextField tfClass;        File[] fileArray;   // 檔案夾下所有檔案                                                                        1    int NUM_IMG = 0;    // 檔案總數目    int index   = 0;    // 當前檔案的序號    private int idImg = 1;    JLabel jlbImg1 = null;    JLabel jlbImg2 = null;    JLabel jlbImg3 = null;        /**     * Launch the application.     */class myFileFilter implements FileFilter{                                                 @Override          public boolean accept(File pathname) {              String filename = pathname.getName().toLowerCase();              if(filename.contains(".jpg")){                  return false;              }else{                  return true;              }          }      }                                                         //2    public static void main(String[] args) {        EventQueue.invokeLater(new Runnable() {            public void run() {                try {                    Guess01 frame = new Guess01();                    frame.setVisible(true);                } catch (Exception e) {                    e.printStackTrace();                }            }        });    }    /**     * Create the frame.     */    public Guess01() {        setTitle("\u731C\u731C\u770B\u6E38\u620FV0.1");        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);        setBounds(100, 100, 700, 530);        contentPane = new JPanel();        contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));        setContentPane(contentPane);        contentPane.setLayout(null);                  // 選擇目錄 按鈕的處理常式        JButton btnDir = new JButton("\u9009\u62E9\u76EE\u5F55");        btnDir.addActionListener(new ActionListener() {           public void actionPerformed(ActionEvent arg0) {                                                                      //3          JFileChooser jfc=new JFileChooser();                   jfc.setFileSelectionMode(JFileChooser.FILES_AND_DIRECTORIES );                   jfc.showDialog(new JLabel(), "選擇");                   File file=jfc.getSelectedFile();                  tfDir.setText(file.getAbsolutePath());                 if(file!=null && file.isDirectory()){                                                                         //4                     // 擷取檔案夾下所有的檔案                     fileArray = file.listFiles();                     NUM_IMG = fileArray.length;                 }                        }        });        btnDir.setBounds(26, 26, 93, 23);        contentPane.add(btnDir);                // 文字框，顯示目錄        tfDir = new JTextField();        tfDir.setEditable(false);        tfDir.setBounds(125, 27, 363, 21);        contentPane.add(tfDir);        tfDir.setColumns(10);                // 選擇班級 按鈕的處理常式        JButton btnClass = new JButton("\u9009\u62E9\u73ED\u7EA7");        btnClass.addActionListener(new ActionListener() {            public void actionPerformed(ActionEvent e) {                                                           //5            JFileChooser jfc=new JFileChooser();                  jfc.setFileSelectionMode(JFileChooser.FILES_AND_DIRECTORIES );                  jfc.showDialog(new JLabel(), "選擇");                  File file=jfc.getSelectedFile();                tfClass.setText(file.getAbsolutePath());                                                                //6            }        });        btnClass.setBounds(26, 59, 93, 23);        contentPane.add(btnClass);                // 文字框，顯示班級檔案        tfClass = new JTextField();        tfClass.setEditable(false);        tfClass.setBounds(125, 60, 363, 21);        contentPane.add(tfClass);        tfClass.setColumns(10);                // 標籤，顯示帶猜測學生姓名        JLabel lbGuessName = new JLabel("\u59D3\u540D");        lbGuessName.setBounds(259, 91, 102, 23);        contentPane.add(lbGuessName);                // 標籤，顯示第一個學生相片        JLabel lblImg1 = new JLabel("\u56FE\u72471");        lblImg1.addMouseListener(new MouseAdapter() {            @Override            public void mouseClicked(MouseEvent arg0) {                            }        });        lblImg1.setBounds(105, 290, 183, 178);        contentPane.add(lblImg1);                    //7        jlbImg1 = new JLabel();        jlbImg1.setBackground(Color.RED);        jlbImg1.setBounds(26, 155, 185,201);                this.add(jlbImg1);                                                         //8                // 標籤，顯示第二個學生相片        JLabel lblImg2 = new JLabel("\u56FE\u72472");        lblImg2.addMouseListener(new MouseAdapter() {            @Override            public void mouseClicked(MouseEvent e) {                            }        });        lblImg2.setForeground(Color.BLACK);        lblImg2.setBackground(SystemColor.inactiveCaption);        lblImg2.setBounds(330, 290, 183, 172);        contentPane.add(lblImg2);                            //9        jlbImg2 = new JLabel();        jlbImg2.setBackground(Color.RED);        jlbImg2.setBounds(241, 155, 185, 201);        this.add(jlbImg2);                                 //10                // 標籤，顯示第三個學生相片        JLabel lblImg3 = new JLabel("\u56FE\u72473");        lblImg3.addMouseListener(new MouseAdapter() {            @Override            public void mouseClicked(MouseEvent e) {                            }        });        lblImg3.setBounds(540, 290, 183, 172);        contentPane.add(lblImg3);        jlbImg3 = new JLabel();                            //11        jlbImg3.setBackground(Color.RED);        jlbImg3.setBounds(456, 155, 185, 201);        this.add(jlbImg3);                                 //12                // 再猜一次 按鈕，點擊則更新相應的三張圖片 與 帶猜測學生姓名        final JButton btnGuessAgain = new JButton("\u518D\u731C\u4E00\u6B21");        btnGuessAgain.addActionListener(new ActionListener() {            public void actionPerformed(ActionEvent e) {                                                                     //13            if(e.getSource()==btnGuessAgain ){ //如果是next按鈕                    String strTmp = fileArray[index].toString();                    index++;                    if(index==NUM_IMG)                        index = 0;                    jlbImg1.setIcon(new ImageIcon(strTmp));                                        index++;                    jlbImg2.setIcon(new ImageIcon(strTmp));                    index++;                    if(e.getSource()==btnGuessAgain ){ //如果是next按鈕                        String strTmp2 = fileArray[index].toString();                        index++;                                               jlbImg2.setIcon(new ImageIcon(strTmp2));                                                index++;                                                                                                          }                                   }   String strTmp1 = fileArray[index].toString();                    index++;                    jlbImg3.setIcon(new ImageIcon(strTmp1));               }                                                                       //14        });        btnGuessAgain.setBounds(250, 430, 93, 23);        contentPane.add(btnGuessAgain);    }}

總結：今天，終於可以在老師給的代碼上顯示照片了。設定了三個 jlbImg空白變數，讓三張照片隨著jlblmg插入JLabel中。不足的是，怎麼也弄不好隨機顯示圖片，困惑的我，很難為情。我相信自己有一天可以做到的，只需要我努力奮鬥。