201271050130-滕江南-《面向对象程序设计（java）》第十五周学习总结

201271050130-滕江南-《面向对象程序设计（java）》第十五周学习总结

博文正文开头格式：（2分）

项目	内容
这个作业属于哪个课程	https://www.cnblogs.com/nwnu-daizh/
这个作业的要求在哪里	https://www.cnblogs.com/nwnu-daizh/p/11435127.html
作业学习目标	(1) 掌握菜单组件用途及常用API； (2) 掌握对话框组件用途及常用API； (3) 学习设计简单应用程序的GUI。

随笔博文正文内容包括：

第一部分：总结菜单、对话框两类组件用途及常用API（30分）

1、菜单

   首先创建一个菜单栏 菜单栏是一个可以添加到容器组件任何位置 的组件。通常放置在框架的顶部。 JMenuBarmenuBar=new JMenuBar();

（1）调用框架的setJMenuBar方法可将一个菜单栏对 象添加到框架上 frame.setJMenuBar（menuBar）;

（2）创建菜单对象，并将菜单对象添加到菜单栏中 JMenueditMenu=new Jmenu("Edit"); menuBar.add(editMenu);
（3）向菜单对象添加一个菜单项。向菜单对象添加一个菜单项。 JMenItempasteItem=new JMenItem(); editMenu.add(pasteItem);

（4）向菜单对象添加分隔符行。 editMenu.addSeperator(); 向菜单对象项添加子菜单。 JMenuoptionsMenu=new Jmenu(“option”); editMenu.add(optionsMenu);

2、对话框

选项对话框   创建对话框   数据选择   文件对话框  颜色选择器

(1)对话框是一种大小不能变化、不能有菜单的容器窗口； 对话框不能作为一个应用程序的主框架，而必须包含在其 他的容器中。

(2)选项对话框:JOptionPane提供的对话框是模式对话框。当模 式对话框显示时，它不允许用户输入到程序的 其他的窗口。使用JOptionPane，可以创建和自 定义问题、信息、警告和错误等几种类型的对 话框。

(3)数据交换:输入对话框含有供用户输入文本的文本框、一个确认和取 消按钮,是有模式对话框。当输入对话框可见时,要求用户 输入一个字符串。

(4)文件对话框:专门用于对文件（或目录）进行浏览和选择的对 话框，常用的构造方法: – JFileChooser()：根据用户的缺省目录创建文件对话框 – JFileChooser(File currentDirectory)：根据File型参数 currentDirectory指定的目录创建文件对话框

(5)颜色对话框: javax.swing包中的JColorChooser类的静态方 法: public static Color showDialog(Component component, String title, Color initialColor)创建一个颜色对话框

(6)参数component指定对话框所依赖的组件，title 指定对话框的标题；initialColor 指定对话框返回 的初始颜色，即对话框消失后，返回的默认值。 颜色对话框可根据用户在颜色对话框中选择的颜 色返回一个颜色对象.

第二部分：实验部分

实验1：

测试程序1

• 在elipse IDE中调试运行教材512页程序12-8，结合运行结果理解程序；

package menu;
 
import java.awt.*;
import javax.swing.*;
 
/**
 * @version 1.25 2018-04-10
 * @author Cay Horstmann
 */
public class MenuTest      
{
   public static void main(String[] args)
   {
      EventQueue.invokeLater(() -> {
         MenuFrame frame = new MenuFrame();
         frame.setTitle("MenuTest");  
         frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
         frame.setVisible(true);
      });
   }
}

package menu;
 
import java.awt.event.*;
import javax.swing.*;
 
/**
 * A frame with a sample menu bar.
 */
public class MenuFrame extends JFrame
{
   private static final int DEFAULT_WIDTH = 300;   
   private static final int DEFAULT_HEIGHT = 200;
   private Action saveAction;   
   private Action saveAsAction;
   private JCheckBoxMenuItem readonlyItem;
   private JPopupMenu popup;   
  
   /**
    * A sample action that prints the action name to System.out.
    */
   class TestAction extends AbstractAction
   {
      public TestAction(String name)   
      {
         super(name);   
      }
 
      public void actionPerformed(ActionEvent event)    
      {
         System.out.println(getValue(Action.NAME) + " selected.");
     
      }
   }
 
   public MenuFrame()  
   {
      setSize(DEFAULT_WIDTH, DEFAULT_HEIGHT);
      JMenu fileMenu = new JMenu("File");   
      fileMenu.add(new TestAction("New"));   
      JMenuItem openItem = fileMenu.add(new TestAction("Open"));
      openItem.setAccelerator(KeyStroke.getKeyStroke("ctrl O"));
      fileMenu.addSeparator();
      saveAction = new TestAction("Save");   
      JMenuItem saveItem = fileMenu.add(saveAction);   
      saveItem.setAccelerator(KeyStroke.getKeyStroke("ctrl S"))
      saveAsAction = new TestAction("Save As");  
      fileMenu.add(saveAsAction);   
      fileMenu.addSeparator();     
      fileMenu.add(new AbstractAction("Exit")      
         {
            public void actionPerformed(ActionEvent event)
            {
               System.exit(0);      
            }
         });
      readonlyItem = new JCheckBoxMenuItem("Read-only");   
      readonlyItem.addActionListener(new ActionListener()    
         {
            public void actionPerformed(ActionEvent event)
            {
               boolean saveOk = !readonlyItem.isSelected();      
               saveAction.setEnabled(saveOk);  
               saveAsAction.setEnabled(saveOk); 
            }
         });
 
      ButtonGroup group = new ButtonGroup();
      JRadioButtonMenuItem insertItem = new JRadioButtonMenuItem("Insert");
      insertItem.setSelected(true);    
      JRadioButtonMenuItem overtypeItem = new JRadioButtonMenuItem("Overtype") 
      group.add(insertItem);   
      group.add(overtypeItem);
      TestAction cutAction = new TestAction("Cut");
      cutAction.putValue(Action.SMALL_ICON, new ImageIcon("cut.gif"));
      TestAction copyAction = new TestAction("Copy");   
      copyAction.putValue(Action.SMALL_ICON, new ImageIcon("copy.gif"));   
      TestAction pasteAction = new TestAction("Paste");
      pasteAction.putValue(Action.SMALL_ICON, new ImageIcon("paste.gif"));   
      JMenu editMenu = new JMenu("Edit");  
      editMenu.add(cutAction);  
      editMenu.add(copyAction);
      editMenu.add(pasteAction);
      JMenu optionMenu = new JMenu("Options");
      optionMenu.add(readonlyItem);  
      optionMenu.addSeparator();    
      optionMenu.add(insertItem);
      optionMenu.add(overtypeItem);
      editMenu.addSeparator();  
      editMenu.add(optionMenu); 
      JMenu helpMenu = new JMenu("Help");
      helpMenu.setMnemonic('H'); 
      JMenuItem indexItem = new JMenuItem("Index");
      indexItem.setMnemonic('I');
      helpMenu.add(indexItem);   
      TestAction aboutAction = new TestAction("About");
      aboutAction.putValue(Action.MNEMONIC_KEY, new Integer('A'));
      helpMenu.add(aboutAction); 
      JMenuBar menuBar = new JMenuBar();  
      setJMenuBar(menuBar);  
      menuBar.add(fileMenu);  
      menuBar.add(editMenu);
      menuBar.add(helpMenu)；
      popup = new JPopupMenu();   
      popup.add(cutAction);      
      popup.add(copyAction);
      popup.add(pasteAction);
 
      JPanel panel = new JPanel();    
      panel.setComponentPopupMenu(popup);   
      add(panel); 
   }
}

　　运行结果如下：

测试程序2

• 在elipse IDE中调试运行教材517页程序12-9，结合运行结果理解程序；

package toolBar;

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

/**
 * @version 1.14 2015-06-12
 * @author Cay Horstmann
 */
public class ToolBarTest
{
   public static void main(String[] args)
   {
      EventQueue.invokeLater(() -> {
         ToolBarFrame frame = new ToolBarFrame();
         frame.setTitle("ToolBarTest");
         frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
         frame.setVisible(true);
      });
   }
}

package toolBar;

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

/**
 * 带有工具栏和菜单的框架，用于颜色变化。
 */
public class ToolBarFrame extends JFrame
{
   private static final int DEFAULT_WIDTH = 300;
   private static final int DEFAULT_HEIGHT = 200;
   private JPanel panel;

   public ToolBarFrame()
   {
      setSize(DEFAULT_WIDTH, DEFAULT_HEIGHT);

      // 添加颜色变化面板

      panel = new JPanel();
      add(panel, BorderLayout.CENTER);

      // 设置动作
      Action blueAction = new ColorAction("Blue", new ImageIcon("blue-ball.gif"), Color.BLUE);
      Action yellowAction = new ColorAction("Yellow", new ImageIcon("yellow-ball.gif"),
            Color.YELLOW);
      Action redAction = new ColorAction("Red", new ImageIcon("red-ball.gif"), Color.RED);

      Action exitAction = new AbstractAction("Exit", new ImageIcon("exit.gif"))
         {
            public void actionPerformed(ActionEvent event)
            {
               System.exit(0);
            }
         };
      exitAction.putValue(Action.SHORT_DESCRIPTION, "Exit");

      // 填充工具栏

      JToolBar bar = new JToolBar();
      bar.add(blueAction);
      bar.add(yellowAction);
      bar.add(redAction);
      bar.addSeparator();
      bar.add(exitAction);
      add(bar, BorderLayout.NORTH);

      // 填充菜单

      JMenu menu = new JMenu("Color");
      menu.add(yellowAction);
      menu.add(blueAction);
      menu.add(redAction);
      menu.add(exitAction);
      JMenuBar menuBar = new JMenuBar();
      menuBar.add(menu);
      setJMenuBar(menuBar);
   }

   /**
    * 颜色动作将帧的背景设置为给定的颜色。
    */
   class ColorAction extends AbstractAction
   {
      public ColorAction(String name, Icon icon, Color c)
      {
         putValue(Action.NAME, name);
         putValue(Action.SMALL_ICON, icon);
         putValue(Action.SHORT_DESCRIPTION, name + " background");
         putValue("Color", c);
      }

      public void actionPerformed(ActionEvent event)
      {
         Color c = (Color) getValue("Color");
         panel.setBackground(c);
      }
   }
}

运行情况如下：

测试程序3

• 在elipse IDE中调试运行教材544页程序12-15、12-16，结合运行结果理解程序；

  package optionDialog;
  
  import java.awt.*;
  import javax.swing.*;
  
  /**
   * @version 1.34 2015-06-12
   * @author Cay Horstmann
   */
  public class OptionDialogTest
  {
     public static void main(String[] args)
     {
        EventQueue.invokeLater(() -> {
           JFrame frame = new OptionDialogFrame();
           frame.setTitle("OptionDialogTest");
           frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
           frame.setVisible(true);
        });
     }
  }

  package optionDialog;

  import javax.swing.*;

  /**
  * A panel with radio buttons inside a titled border.
  */
  public class ButtonPanel extends JPanel
  {
  private ButtonGroup group;

  /**
  * Constructs a button panel.
  * @param title the title shown in the border
  * @param options an array of radio button labels
  */
  public ButtonPanel(String title, String... options)
  {
  setBorder(BorderFactory.createTitledBorder(BorderFactory.createEtchedBorder(), title));
  setLayout(new BoxLayout(this, BoxLayout.Y_AXIS));
  group = new ButtonGroup();

  // make one radio button for each option
  for (String option : options)
  {
  JRadioButton b = new JRadioButton(option);
  b.setActionCommand(option);
  add(b);
  group.add(b);
  b.setSelected(option == options[0]);
  }
  }

  /**
  * Gets the currently selected option.
  * @return the label of the currently selected radio button.
  */
  public String getSelection()
  {
  return group.getSelection().getActionCommand();
  }
  }

  package optionDialog;
  
  import java.awt.*;
  import java.awt.event.*;
  import java.awt.geom.*;
  import java.util.*;
  import javax.swing.*;
  
  /**
   * A frame that contains settings for selecting various option dialogs.
   */
  public class OptionDialogFrame extends JFrame
  {
     private ButtonPanel typePanel;
     private ButtonPanel messagePanel;
     private ButtonPanel messageTypePanel;
     private ButtonPanel optionTypePanel;
     private ButtonPanel optionsPanel;
     private ButtonPanel inputPanel;
     private String messageString = "Message";
     private Icon messageIcon = new ImageIcon("blue-ball.gif");
     private Object messageObject = new Date();
     private Component messageComponent = new SampleComponent();
  
     public OptionDialogFrame()
     {
        JPanel gridPanel = new JPanel();
        gridPanel.setLayout(new GridLayout(2, 3));
  
        typePanel = new ButtonPanel("Type", "Message", "Confirm", "Option", "Input");
        messageTypePanel = new ButtonPanel("Message Type", "ERROR_MESSAGE", "INFORMATION_MESSAGE",
              "WARNING_MESSAGE", "QUESTION_MESSAGE", "PLAIN_MESSAGE");
        messagePanel = new ButtonPanel("Message", "String", "Icon", "Component", "Other", 
              "Object[]");
        optionTypePanel = new ButtonPanel("Confirm", "DEFAULT_OPTION", "YES_NO_OPTION",
              "YES_NO_CANCEL_OPTION", "OK_CANCEL_OPTION");
        optionsPanel = new ButtonPanel("Option", "String[]", "Icon[]", "Object[]");
        inputPanel = new ButtonPanel("Input", "Text field", "Combo box");
  
        gridPanel.add(typePanel);
        gridPanel.add(messageTypePanel);
        gridPanel.add(messagePanel);
        gridPanel.add(optionTypePanel);
        gridPanel.add(optionsPanel);
        gridPanel.add(inputPanel);
  
        // add a panel with a Show button
  
        JPanel showPanel = new JPanel();
        JButton showButton = new JButton("Show");
        showButton.addActionListener(new ShowAction());
        showPanel.add(showButton);
  
        add(gridPanel, BorderLayout.CENTER);
        add(showPanel, BorderLayout.SOUTH);
        pack();
     }
  
     /**
      * Gets the currently selected message.
      * @return a string, icon, component, or object array, depending on the Message panel selection
      */
     public Object getMessage()
     {
        String s = messagePanel.getSelection();
        if (s.equals("String")) return messageString;
        else if (s.equals("Icon")) return messageIcon;
        else if (s.equals("Component")) return messageComponent;
        else if (s.equals("Object[]")) return new Object[] { messageString, messageIcon,
              messageComponent, messageObject };
        else if (s.equals("Other")) return messageObject;
        else return null;
     }
  
     /**
      * Gets the currently selected options.
      * @return an array of strings, icons, or objects, depending on the Option panel selection
      */
     public Object[] getOptions()
     {
        String s = optionsPanel.getSelection();
        if (s.equals("String[]")) return new String[] { "Yellow", "Blue", "Red" };
        else if (s.equals("Icon[]")) return new Icon[] { new ImageIcon("yellow-ball.gif"),
              new ImageIcon("blue-ball.gif"), new ImageIcon("red-ball.gif") };
        else if (s.equals("Object[]")) return new Object[] { messageString, messageIcon,
              messageComponent, messageObject };
        else return null;
     }
  
     /**
      * Gets the selected message or option type
      * @param panel the Message Type or Confirm panel
      * @return the selected XXX_MESSAGE or XXX_OPTION constant from the JOptionPane class
      */
     public int getType(ButtonPanel panel)
     {
        String s = panel.getSelection();
        try
        {
           return JOptionPane.class.getField(s).getInt(null);
        }
        catch (Exception e)
        {
           return -1;
        }
     }
  
     /**
      * The action listener for the Show button shows a Confirm, Input, Message, or Option dialog
      * depending on the Type panel selection.
      */
     private class ShowAction implements ActionListener
     {
        public void actionPerformed(ActionEvent event)
        {
           if (typePanel.getSelection().equals("Confirm")) JOptionPane.showConfirmDialog(
                 OptionDialogFrame.this, getMessage(), "Title", getType(optionTypePanel),
                 getType(messageTypePanel));
           else if (typePanel.getSelection().equals("Input"))
           {
              if (inputPanel.getSelection().equals("Text field")) JOptionPane.showInputDialog(
                    OptionDialogFrame.this, getMessage(), "Title", getType(messageTypePanel));
              else JOptionPane.showInputDialog(OptionDialogFrame.this, getMessage(), "Title",
                    getType(messageTypePanel), null, new String[] { "Yellow", "Blue", "Red" },
                    "Blue");
           }
           else if (typePanel.getSelection().equals("Message")) JOptionPane.showMessageDialog(
                 OptionDialogFrame.this, getMessage(), "Title", getType(messageTypePanel));
           else if (typePanel.getSelection().equals("Option")) JOptionPane.showOptionDialog(
                 OptionDialogFrame.this, getMessage(), "Title", getType(optionTypePanel),
                 getType(messageTypePanel), null, getOptions(), getOptions()[0]);
        }
     }
  }
  
  /**
   * A component with a painted surface
   */
  
  class SampleComponent extends JComponent
  {
     public void paintComponent(Graphics g)
     {
        Graphics2D g2 = (Graphics2D) g;
        Rectangle2D rect = new Rectangle2D.Double(0, 0, getWidth() - 1, getHeight() - 1);
        g2.setPaint(Color.YELLOW);
        g2.fill(rect);
        g2.setPaint(Color.BLUE);
        g2.draw(rect);
     }
  
     public Dimension getPreferredSize()
     {
        return new Dimension(10, 10);
     }
  }

  运行结果如下：

  

测试程序4

• 在elipse IDE中调试运行教材552页程序12-17、12-18，结合运行结果理解程序；

  package dialog;
  
  import java.awt.*;
  import javax.swing.*;
  
  /**
   * @version 1.34 2012-06-12
   * @author Cay Horstmann
   */
  public class DialogTest
  {
     public static void main(String[] args)
     {
        EventQueue.invokeLater(() -> {
           JFrame frame = new DialogFrame();
           frame.setTitle("DialogTest");
           frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
           frame.setVisible(true);
        });
     }
  }

  package dialog;
  
  import javax.swing.JFrame;
  import javax.swing.JMenu;
  import javax.swing.JMenuBar;
  import javax.swing.JMenuItem;
  
  /**
   * A frame with a menu whose File->About action shows a dialog.
   */
  public class DialogFrame extends JFrame
  {
     private static final int DEFAULT_WIDTH = 300;
     private static final int DEFAULT_HEIGHT = 200;
     private AboutDialog dialog;
  
     public DialogFrame()
     {
        setSize(DEFAULT_WIDTH, DEFAULT_HEIGHT);
  
        // Construct a File menu.
  
        JMenuBar menuBar = new JMenuBar();
        setJMenuBar(menuBar);
        JMenu fileMenu = new JMenu("File");
        menuBar.add(fileMenu);
  
        // Add About and Exit menu items.
  
        // The About item shows the About dialog.
  
        JMenuItem aboutItem = new JMenuItem("About");
        aboutItem.addActionListener(event -> {
           if (dialog == null) // first time
              dialog = new AboutDialog(DialogFrame.this);
           dialog.setVisible(true); // pop up dialog
        });
        fileMenu.add(aboutItem);
  
        // The Exit item exits the program.
  
        JMenuItem exitItem = new JMenuItem("Exit");
        exitItem.addActionListener(event -> System.exit(0));
        fileMenu.add(exitItem);
     }
  }

  package dialog;
  
  import java.awt.BorderLayout;
  
  import javax.swing.JButton;
  import javax.swing.JDialog;
  import javax.swing.JFrame;
  import javax.swing.JLabel;
  import javax.swing.JPanel;
  
  /**
   * A sample modal dialog that displays a message and waits for the user to click the OK button.
   */
  public class AboutDialog extends JDialog
  {
     public AboutDialog(JFrame owner)
     {
        super(owner, "About DialogTest", true);
  
        // add HTML label to center
  
        add(
              new JLabel(
                    "<html><h1><i>Core Java</i></h1><hr>By Cay Horstmann</html>"),
              BorderLayout.CENTER);
  
        // OK button closes the dialog
  
        JButton ok = new JButton("OK");
        ok.addActionListener(event -> setVisible(false));
  
        // add OK button to southern border
  
        JPanel panel = new JPanel();
        panel.add(ok);
        add(panel, BorderLayout.SOUTH);
  
        pack();
     }
  }

  运行结果如下：

•  

实验1：

测试程序5

• 在elipse IDE中调试运行教材556页程序12-19、12-20，结合运行结果理解程序；

  package dataExchange;
   
  import java.awt.*;
  import java.awt.event.*;
  import javax.swing.*;
   
  /**
   * A frame with a menu whose File->Connect action shows a password dialog.
   */
  public class DataExchangeFrame extends JFrame
  {
     public static final int TEXT_ROWS = 20;
     public static final int TEXT_COLUMNS = 40;
     private PasswordChooser dialog = null;
     private JTextArea textArea;
   
     public DataExchangeFrame()
     {
        // 建构档案选单
   
        JMenuBar mbar = new JMenuBar();
        setJMenuBar(mbar);
        JMenu fileMenu = new JMenu("File");
        mbar.add(fileMenu);
   
        //添加连接和退出菜单项
        JMenuItem connectItem = new JMenuItem("Connect");
        connectItem.addActionListener(new ConnectAction());
        fileMenu.add(connectItem);
   
        // 退出项退出程序
   
        JMenuItem exitItem = new JMenuItem("Exit");
        exitItem.addActionListener(event -> System.exit(0));
        fileMenu.add(exitItem);
   
        textArea = new JTextArea(TEXT_ROWS, TEXT_COLUMNS);
        add(new JScrollPane(textArea), BorderLayout.CENTER);
        pack();
     }
   
     /**
      * The Connect action pops up the password dialog.
      */
     private class ConnectAction implements ActionListener
     {
        public void actionPerformed(ActionEvent event)
        {
           // 如果第一次，构造对话框
   
           if (dialog == null) dialog = new PasswordChooser();
   
           //设定预设值
           dialog.setUser(new User("yourname", null));
   
           //弹出对话框
           if (dialog.showDialog(DataExchangeFrame.this, "Connect"))
           {
              // 如果接受，则检索用户输入
              User u = dialog.getUser();
              textArea.append("user name = " + u.getName() + ", password = "
                    + (new String(u.getPassword())) + "
  ");
           }
        }
     }
  }

  package dataExchange;
   
  import java.awt.*;
  import javax.swing.*;
   
  /**
   * @version 1.34 2015-06-12
   * @author Cay Horstmann
   */
  public class DataExchangeTest
  {
     public static void main(String[] args)
     {
        EventQueue.invokeLater(() -> {
           JFrame frame = new DataExchangeFrame();
           frame.setTitle("DataExchangeTest");
           frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
           frame.setVisible(true);
        });
     }
  }

  package dataExchange;
   
  import java.awt.BorderLayout;
  import java.awt.Component;
  import java.awt.Frame;
  import java.awt.GridLayout;
   
  import javax.swing.JButton;
  import javax.swing.JDialog;
  import javax.swing.JLabel;
  import javax.swing.JPanel;
  import javax.swing.JPasswordField;
  import javax.swing.JTextField;
  import javax.swing.SwingUtilities;
   
  /**
   * A password chooser that is shown inside a dialog
   */
  public class PasswordChooser extends JPanel
  {
     private JTextField username;
     private JPasswordField password;
     private JButton okButton;
     private boolean ok;
     private JDialog dialog;
   
     public PasswordChooser()
     {
        setLayout(new BorderLayout());
   
        // 构造带有用户名和密码字段的面板
   
        JPanel panel = new JPanel();
        panel.setLayout(new GridLayout(2, 2));
        panel.add(new JLabel("User name:"));
        panel.add(username = new JTextField(""));
        panel.add(new JLabel("Password:"));
        panel.add(password = new JPasswordField(""));
        add(panel, BorderLayout.CENTER);
   
        //创建“确定”并取消终止对话框的按钮
   
        okButton = new JButton("Ok");
        okButton.addActionListener(event -> {
           ok = true;
           dialog.setVisible(false);
        });
   
        JButton cancelButton = new JButton("Cancel");
        cancelButton.addActionListener(event -> dialog.setVisible(false));
   
        // 添加按钮到南部边界
   
        JPanel buttonPanel = new JPanel();
        buttonPanel.add(okButton);
        buttonPanel.add(cancelButton);
        add(buttonPanel, BorderLayout.SOUTH);
     }
   
     /**
      * Sets the dialog defaults.
      * @param u the default user information
      */
     public void setUser(User u)
     {
        username.setText(u.getName());
     }
   
     /**
      * Gets the dialog entries.
      * @return a User object whose state represents the dialog entries
      */
     public User getUser()
     {
        return new User(username.getText(), password.getPassword());
     }
   
     /**
      * Show the chooser panel in a dialog
      * @param parent a component in the owner frame or null
      * @param title the dialog window title
      */
     public boolean showDialog(Component parent, String title)
     {
        ok = false;
   
        // 找到所有者框架
        Frame owner = null;
        if (parent instanceof Frame)
           owner = (Frame) parent;
        else
           owner = (Frame) SwingUtilities.getAncestorOfClass(Frame.class, parent);
   
        // 如果第一次，或者所有者已经改变，请创建新的对话框
   
        if (dialog == null || dialog.getOwner() != owner)
        {
           dialog = new JDialog(owner, true);
           dialog.add(this);
           dialog.getRootPane().setDefaultButton(okButton);
           dialog.pack();
        }
   
        // 设定标题及显示对话框
   
        dialog.setTitle(title);
        dialog.setVisible(true);
        return ok;
     }
  }

  package dataExchange;
   
  /**
   * A user has a name and password. For security reasons, the password is stored as a char[], not a
   * String.
   */
  public class User
  {
     private String name;
     private char[] password;
   
     public User(String aName, char[] aPassword)
     {
        name = aName;
        password = aPassword;
     }
   
     public String getName()
     {
        return name;
     }
   
     public char[] getPassword()
     {
        return password;
     }
   
     public void setName(String aName)
     {
        name = aName;
     }
   
     public void setPassword(char[] aPassword)
     {
        password = aPassword;
     }
  }

  运行结果如下：

• 

测试程序6

• 在elipse IDE中调试运行教材556页程序12-21、12-22、12-23，结合程序运行结果理解程序；

  package fileChooser;
   
  import java.awt.*;
  import javax.swing.*;
   
  /**
   * @version 1.25 2015-06-12
   * @author Cay Horstmann
   */
  public class FileChooserTest
  {
     public static void main(String[] args)
     {
        EventQueue.invokeLater(() -> {
           JFrame frame = new ImageViewerFrame();
           frame.setTitle("FileChooserTest");
           frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
           frame.setVisible(true);
        });
     }
  }

  package fileChooser;
   
  import java.io.*;
  import javax.swing.*;
  import javax.swing.filechooser.*;
  import javax.swing.filechooser.FileFilter;
   
  /**
   * A file view that displays an icon for all files that match a file filter.
   */
  public class FileIconView extends FileView
  {
     private FileFilter filter;
     private Icon icon;
   
     /**
      * Constructs a FileIconView.
      * @param aFilter a file filter--all files that this filter accepts will be shown
      * with the icon.
      * @param anIcon--the icon shown with all accepted files.
      */
     public FileIconView(FileFilter aFilter, Icon anIcon)
     {
        filter = aFilter;
        icon = anIcon;
     }
   
     public Icon getIcon(File f)
     {
        if (!f.isDirectory() && filter.accept(f)) return icon;
        else return null;
     }
  }

  package fileChooser;
   
  import java.awt.*;
  import java.io.*;
   
  import javax.swing.*;
   
  /**
   * A file chooser accessory that previews images.
   */
  public class ImagePreviewer extends JLabel
  {
     /**
      * Constructs an ImagePreviewer.
      * @param chooser the file chooser whose property changes trigger an image
      *        change in this previewer
      */
     public ImagePreviewer(JFileChooser chooser)
     {
        setPreferredSize(new Dimension(100, 100));
        setBorder(BorderFactory.createEtchedBorder());
   
        chooser.addPropertyChangeListener(event -> {
           if (event.getPropertyName() == JFileChooser.SELECTED_FILE_CHANGED_PROPERTY)
           {
              //用户选择了一个新文件
              File f = (File) event.getNewValue();
              if (f == null)
              {
                 setIcon(null);
                 return;
              }
   
              //将影像读取成图示
              ImageIcon icon = new ImageIcon(f.getPath());
   
              // 如果图标太大，无法安装，请缩放
              if (icon.getIconWidth() > getWidth())
                 icon = new ImageIcon(icon.getImage().getScaledInstance(
                       getWidth(), -1, Image.SCALE_DEFAULT));
   
              setIcon(icon);
           }
        });
     }
  }

  package fileChooser;
   
  import java.io.*;
   
  import javax.swing.*;
  import javax.swing.filechooser.*;
  import javax.swing.filechooser.FileFilter;
   
  /**
   * A frame that has a menu for loading an image and a display area for the
   * loaded image.
   */
  public class ImageViewerFrame extends JFrame
  {
     private static final int DEFAULT_WIDTH = 300;
     private static final int DEFAULT_HEIGHT = 400;
     private JLabel label;
     private JFileChooser chooser;
   
     public ImageViewerFrame()
     {
        setSize(DEFAULT_WIDTH, DEFAULT_HEIGHT);
   
        // 设置菜单栏
        JMenuBar menuBar = new JMenuBar();
        setJMenuBar(menuBar);
   
        JMenu menu = new JMenu("File");
        menuBar.add(menu);
   
        JMenuItem openItem = new JMenuItem("Open");
        menu.add(openItem);
        openItem.addActionListener(event -> {
           chooser.setCurrentDirectory(new File("."));
   
           // 显示文件选择器对话框
              int result = chooser.showOpenDialog(ImageViewerFrame.this);
   
              // 如果图像文件被接受，将其设置为标签的图标
              if (result == JFileChooser.APPROVE_OPTION)
              {
                 String name = chooser.getSelectedFile().getPath();
                 label.setIcon(new ImageIcon(name));
                 pack();
              }
           });
   
        JMenuItem exitItem = new JMenuItem("Exit");
        menu.add(exitItem);
        exitItem.addActionListener(event -> System.exit(0));
   
        //使用标签显示影像
        label = new JLabel();
        add(label);
   
        // 设置文件选择器
        chooser = new JFileChooser();
   
        //接受所有以之结尾的影像档案。JPG。杰伯图形交换格式
        FileFilter filter = new FileNameExtensionFilter(
              "Image files", "jpg", "jpeg", "gif");
        chooser.setFileFilter(filter);
   
        chooser.setAccessory(new ImagePreviewer(chooser));
   
        chooser.setFileView(new FileIconView(filter, new ImageIcon("palette.gif")));
     }
  }

  运行结果如下：

• 

测试程序7

• 在elipse IDE中调试运行教材570页程序12-24，结合运行结果理解程序；

  package colorChooser;
   
  import javax.swing.*;
   
  /**
   * A frame with a color chooser panel
   */
  public class ColorChooserFrame extends JFrame
  {
     private static final int DEFAULT_WIDTH = 300;
     private static final int DEFAULT_HEIGHT = 200;
   
     public ColorChooserFrame()
     {     
        setSize(DEFAULT_WIDTH, DEFAULT_HEIGHT);
   
        // 添加颜色选择器面板到框架
   
        ColorChooserPanel panel = new ColorChooserPanel();
        add(panel);
     }
  }

  package colorChooser;
   
  import java.awt.Color;
  import java.awt.Frame;
  import java.awt.event.ActionEvent;
  import java.awt.event.ActionListener;
   
  import javax.swing.JButton;
  import javax.swing.JColorChooser;
  import javax.swing.JDialog;
  import javax.swing.JPanel;
   
  /**
   * A panel with buttons to pop up three types of color choosers
   */
  public class ColorChooserPanel extends JPanel
  {
     public ColorChooserPanel()
     {
        JButton modalButton = new JButton("Modal");
        modalButton.addActionListener(new ModalListener());
        add(modalButton);
   
        JButton modelessButton = new JButton("Modeless");
        modelessButton.addActionListener(new ModelessListener());
        add(modelessButton);
   
        JButton immediateButton = new JButton("Immediate");
        immediateButton.addActionListener(new ImmediateListener());
        add(immediateButton);
     }
   
     /**
      * This listener pops up a modal color chooser
      */
     private class ModalListener implements ActionListener
     {
        public void actionPerformed(ActionEvent event)
        {
           Color defaultColor = getBackground();
           Color selected = JColorChooser.showDialog(ColorChooserPanel.this, "Set background",
                 defaultColor);
           if (selected != null) setBackground(selected);
        }
     }
   
     /**
      * This listener pops up a modeless color chooser. The panel color is changed when the user
      * clicks the OK button.
      */
     private class ModelessListener implements ActionListener
     {
        private JDialog dialog;
        private JColorChooser chooser;
   
        public ModelessListener()
        {
           chooser = new JColorChooser();
           dialog = JColorChooser.createDialog(ColorChooserPanel.this, "Background Color",
                 false /* not modal */, chooser,
                 event -> setBackground(chooser.getColor()),
                 null /* no Cancel button listener */);
        }
   
        public void actionPerformed(ActionEvent event)
        {
           chooser.setColor(getBackground());
           dialog.setVisible(true);
        }
     }
   
     /**
      * This listener pops up a modeless color chooser. The panel color is changed immediately when
      * the user picks a new color.
      */
     private class ImmediateListener implements ActionListener
     {
        private JDialog dialog;
        private JColorChooser chooser;
   
        public ImmediateListener()
        {
           chooser = new JColorChooser();
           chooser.getSelectionModel().addChangeListener(
                 event -> setBackground(chooser.getColor()));
   
           dialog = new JDialog((Frame) null, false /* not modal */);
           dialog.add(chooser);
           dialog.pack();
        }
   
        public void actionPerformed(ActionEvent event)
        {
           chooser.setColor(getBackground());
           dialog.setVisible(true);
        }
     }
  }

  package colorChooser;
   
  import java.awt.*;
  import javax.swing.*;
   
  /**
   * @version 1.04 2015-06-12
   * @author Cay Horstmann
   */
  public class ColorChooserTest
  {
     public static void main(String[] args)
     {
        EventQueue.invokeLater(() -> {
           JFrame frame = new ColorChooserFrame();
           frame.setTitle("ColorChooserTest");
           frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
           frame.setVisible(true);
        });
     }

  运行结果如下：

实验总结：（16分）

 　　本周学习了菜单和对话框，按照要求完成了实验的程序测试。之前不知道有整理好的代码可以直接导入，都是自己敲代码进行验证，时间花费得比较多，而且有些程序也没有实现。个人也产生了懈怠情绪，导致部分作业复制粘贴。经过老师的教育，也深刻认真的反省了自己 的错误。我以后会认真完成作业，不懂就问，脚踏实地。