张云飞 201771010143 《面对对象程序设计（java）》第十四周学习总结 第十三组

1、实验目的与要求

(1) 掌握GUI布局管理器用法；

(2) 掌握各类Java Swing组件用途及常用API；

2、实验内容和步骤

实验1： 导入第12章示例程序，测试程序并进行组内讨论。

测试程序1

l  在elipse IDE中运行教材479页程序12-1，结合运行结果理解程序；

l  掌握各种布局管理器的用法；

l  理解GUI界面中事件处理技术的用途。

l  在布局管理应用代码处添加注释；

代码：

package calculator;

import javax.swing.*;

/**
* A frame with a calculator panel.
*/
public class CalculatorFrame extends JFrame
{
public CalculatorFrame()
{
add(new CalculatorPanel());
pack();
}
}

CalculatorFrame

package calculator;

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

/**
* @version 1.34 2015-06-12
* @author Cay Horstmann
*/
public class Calculator
{
public static void main(String[] args)
{
EventQueue.invokeLater(() -> {
CalculatorFrame frame = new CalculatorFrame();
frame.setTitle("Calculator");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
});
}
}

Calculator

package calculator;

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

/**
* 具有计算器按钮和结果显示的面板
*/
public class CalculatorPanel extends JPanel {
private JButton display;
private JPanel panel;
private double result;
private String lastCommand;
private boolean start;

public CalculatorPanel() {
setLayout(new BorderLayout());

result = 0;
lastCommand = "=";
start = true;

// 添加display

display = new JButton("0");
display.setEnabled(false);
add(display, BorderLayout.NORTH);

ActionListener insert = new InsertAction();
ActionListener command = new CommandAction();

// 在4×4网格中添加按钮

panel = new JPanel();
panel.setLayout(new GridLayout(4, 4));

addButton("7", insert);
addButton("8", insert);
addButton("9", insert);
addButton("/", command);

addButton("4", insert);
addButton("5", insert);
addButton("6", insert);
addButton("*", command);

addButton("1", insert);
addButton("2", insert);
addButton("3", insert);
addButton("-", command);

addButton("0", insert);
addButton(".", insert);
addButton("=", command);
addButton("+", command);

add(panel, BorderLayout.CENTER);// 把面板添加在边框布局的中央
}

/**
* 向中心面板添加一个按钮
*
* @param label the button label
* @param listener the button listener
*/
private void addButton(String label, ActionListener listener) {
JButton button = new JButton(label);
button.addActionListener(listener);
panel.add(button);
}

/**
* 此操作将按钮操作字符串插入到显示文本的末尾
*/
private class InsertAction implements ActionListener {
public void actionPerformed(ActionEvent event) {
String input = event.getActionCommand();// 标识此事件命令的字符串
if (start) {
display.setText("");
start = false;
}
display.setText(display.getText() + input);
}
}

/**
* 此操作执行按钮操作字符串所表示的命令
*/
private class CommandAction implements ActionListener {
public void actionPerformed(ActionEvent event) {
String command = event.getActionCommand();

if (start) {
if (command.equals("-"))// 负数的情况
{
display.setText(command);
start = false;
} else
lastCommand = command;
} else {
calculate(Double.parseDouble(display.getText()));// 把display中的string转换为double
lastCommand = command;
start = true;
}
}
}

/**
* 执行即将发生的计算
*
* @param x值与先前结果一起累积。
*/
public void calculate(double x) {
if (lastCommand.equals("+"))
result += x;
else if (lastCommand.equals("-"))
result -= x;
else if (lastCommand.equals("*"))
result *= x;
else if (lastCommand.equals("/"))
result /= x;
else if (lastCommand.equals("="))
result = x;
display.setText("" + result);// 在double前添加""可转换为string
}
}

CalculatorPanel

结果：

测试程序2

l 在elipse IDE中调试运行教材486页程序12-2，结合运行结果理解程序；

l 掌握各种文本组件的用法；

l 记录示例代码阅读理解中存在的问题与疑惑。

 

package Forth;

import java.awt.BorderLayout;
import java.awt.GridLayout;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JPasswordField;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.JTextField;
import javax.swing.SwingConstants;

/**
* A frame with sample text components.
*/
public class TextComponentFrame extends JFrame
{
public static final int TEXTAREA_ROWS = 8;
public static final int TEXTAREA_COLUMNS = 20;

public TextComponentFrame()
{
//本窗口有文本域和密码域
JTextField textField = new JTextField();
JPasswordField passwordField = new JPasswordField();

//定义一个Panel,设置了表格布局管理器并指定行与列

JPanel northPanel = new JPanel();
northPanel.setLayout(new GridLayout(2, 2));
// 添加文本域的标签

northPanel.add(new JLabel("User name: ", SwingConstants.RIGHT));
northPanel.add(textField);//将文本域添加到panel
northPanel.add(new JLabel("Password: ", SwingConstants.RIGHT));
northPanel.add(passwordField);

add(northPanel, BorderLayout.NORTH);//将pannel添加到frame

JTextArea textArea = new JTextArea(TEXTAREA_ROWS, TEXTAREA_COLUMNS);
JScrollPane scrollPane = new JScrollPane(textArea);

add(scrollPane, BorderLayout.CENTER);

// 添加按钮以将文本附加到文本区域

JPanel southPanel = new JPanel();

//定义一个按钮，添加到frame下方，并定义监听事件，点击按钮，文本区显示用户名与密码
JButton insertButton = new JButton("Insert");
southPanel.add(insertButton);
insertButton.addActionListener(event ->
textArea.append("User name: " + textField.getText() + " Password: "
+ new String(passwordField.getPassword()) + " "));

add(southPanel, BorderLayout.SOUTH);
pack();
}
}

TextComponentFrame

测试程序3

l 在elipse IDE中调试运行教材489页程序12-3，结合运行结果理解程序；

l 掌握复选框组件的用法；

l 记录示例代码阅读理解中存在的问题与疑惑。 

package practise;

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

/**
* @version 1.34 2015-06-12
* @author Cay Horstmann
*/
public class CheckBoxTest
{
public static void main(String[] args)
{
EventQueue.invokeLater(() -> {
JFrame frame = new CheckBoxFrame();
frame.setTitle("CheckBoxTest");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
});
}
}

CheckBoxTest

 

package practise;

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

/**
* A frame with a sample text label and check boxes for selecting font
* attributes.
*/
public class CheckBoxFrame extends JFrame
{
private JLabel label;
private JCheckBox bold;
private JCheckBox italic;
private static final int FONTSIZE = 24;

public CheckBoxFrame()
{
// add the sample text label
//添加示例文本标签;

label = new JLabel("The quick brown fox jumps over the lazy dog.");
label.setFont(new Font("Serif", Font.BOLD, FONTSIZE));
add(label, BorderLayout.CENTER);

//此侦听器将标签的字体属性设置为复选框状态;

ActionListener listener = event -> {
int mode = 0;
if (bold.isSelected()) mode += Font.BOLD;
if (italic.isSelected()) mode += Font.ITALIC;
label.setFont(new Font("Serif", mode, FONTSIZE));
};

// 添加复选框

JPanel buttonPanel = new JPanel();

bold = new JCheckBox("Bold");
bold.addActionListener(listener);
bold.setSelected(true);
buttonPanel.add(bold);

italic = new JCheckBox("Italic");
italic.addActionListener(listener);
buttonPanel.add(italic);

add(buttonPanel, BorderLayout.SOUTH);
pack();
}
}

CheckBoxFrame

测试程序4

l 在elipse IDE中调试运行教材491页程序12-4，运行结果理解程序；

l 掌握单选按钮组件的用法；

l 记录示例代码阅读理解中存在的问题与疑惑。

package Second;

import java.awt.*;

import javax.swing.*;

/**
* @version 1.34 2015-06-12
* @author Cay Horstmann
*/
public class RadioButtonTest
{
public static void main(String[] args)
{
EventQueue.invokeLater(() -> {
JFrame frame = new RadioButtonFrame();
frame.setTitle("RadioButtonTest");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
});
}
}

RadioButtonTest

package Second;

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

/**
* A frame with a sample text label and radio buttons for selecting font sizes.
*/
public class RadioButtonFrame extends JFrame
{
private JPanel buttonPanel;
private ButtonGroup group;
private JLabel label;
private static final int DEFAULT_SIZE = 36;

public RadioButtonFrame()
{
// 添加示例文本标签

label = new JLabel("The quick brown fox jumps over the lazy dog.");
label.setFont(new Font("Serif", Font.PLAIN, DEFAULT_SIZE));
add(label, BorderLayout.CENTER);

// 添加单选按钮;

buttonPanel = new JPanel();
group = new ButtonGroup();

addRadioButton("Small", 8);
addRadioButton("Medium", 12);
addRadioButton("Large", 18);
addRadioButton("Extra large", 36);

add(buttonPanel, BorderLayout.SOUTH);
pack();
}

/**
* Adds a radio button that sets the font size of the sample text.
* @param name the string to appear on the button
* @param size the font size that this button sets
*/
public void addRadioButton(String name, int size)
{
boolean selected = size == DEFAULT_SIZE;
JRadioButton button = new JRadioButton(name, selected);
group.add(button);
buttonPanel.add(button);

// 此监听器设定标签字型大小

ActionListener listener = event -> label.setFont(new Font("Serif", Font.PLAIN, size));

button.addActionListener(listener);
}
}

RadioButtonFrame

测试程序5

l 在elipse IDE中调试运行教材494页程序12-5，结合运行结果理解程序；

l 掌握边框的用法；

l 记录示例代码阅读理解中存在的问题与疑惑。

package Third;

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

/**
* @version 1.34 2015-06-13
* @author Cay Horstmann
*/
public class BorderTest
{
public static void main(String[] args)
{
EventQueue.invokeLater(() -> {
JFrame frame = new BorderFrame();
frame.setTitle("BorderTest");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
});
}
}

BorderTest

package Third;

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

/**
* A frame with radio buttons to pick a border style.
*/
public class BorderFrame extends JFrame
{
private JPanel demoPanel;
private JPanel buttonPanel;
private ButtonGroup group;

public BorderFrame()
{
demoPanel = new JPanel();
buttonPanel = new JPanel();
group = new ButtonGroup();

addRadioButton("Lowered bevel", BorderFactory.createLoweredBevelBorder());//创建一个具有凹面效果的边框；
addRadioButton("Raised bevel", BorderFactory.createRaisedBevelBorder());//创建一个具有凸面效果的边框；
addRadioButton("Etched", BorderFactory.createEtchedBorder());//创建一个具有3D效果的直线边框；
addRadioButton("Line", BorderFactory.createLineBorder(Color.BLUE));//创建一个具有3D效果的蓝色直线边框；
addRadioButton("Matte", BorderFactory.createMatteBorder(10, 10, 10, 10, Color.BLUE));//创建一个用蓝色填充的粗边框；
addRadioButton("Empty", BorderFactory.createEmptyBorder());//创建一个空边框；
//将一个带有标题的蚀刻边框添加到面板；
Border etched = BorderFactory.createEtchedBorder();
Border titled = BorderFactory.createTitledBorder(etched, "Border types");
buttonPanel.setBorder(titled);

setLayout(new GridLayout(2, 1));//设置了表格布局管理器并指定行与列
add(buttonPanel);
add(demoPanel);
pack();
}

public void addRadioButton(String buttonName, Border b)
{
JRadioButton button = new JRadioButton(buttonName);
button.addActionListener(event -> demoPanel.setBorder(b));
group.add(button);
buttonPanel.add(button);
}
}

BorderFrame

测试程序6

l 在elipse IDE中调试运行教材498页程序12-6，结合运行结果理解程序；

l 掌握组合框组件的用法；

l 记录示例代码阅读理解中存在的问题与疑惑。

package comboBox;
import java.awt.*;
import javax.swing.*;
/**
 * @version 1.35 2015-06-12
 * @author Cay Horstmann
 */
public class ComboBoxTest
{
   public static void main(String[] args)
   {
      //lambda表达式
      EventQueue.invokeLater(() -> {
         //构造frame框架对象
         JFrame frame = new ComboBoxFrame();
         //设置标题
         frame.setTitle("ComboBoxTest");
         //设置用户在此窗体上发起 "close" 时默认执行的操作。
         frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
         //设置框架是否可见
         frame.setVisible(true);
      });
   }
}
ComboBoxTest

测试程序7

l 在elipse IDE中调试运行教材501页程序12-7，结合运行结果理解程序；

l 掌握滑动条组件的用法；

l 记录示例代码阅读理解中存在的问题与疑惑。

package comboBox;
import java.awt.BorderLayout;
import java.awt.Font;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
/**
 * 具有示例文本标签和用于选择字体外观的组合框的框架。
 * 组合框：将按钮或可编辑字段与下拉列表组合的组件。
 * 用户可以从下拉列表中选择值，下拉列表在用户请求时显示。
 * 如果使组合框处于可编辑状态，则组合框将包括用户可在其中键入值的可编辑字段。
 */
//ComboBoxFrame继承于JFrame类
public class ComboBoxFrame extends JFrame
{
   //设置ComboBoxFrame的私有属性
   private JComboBox<String> faceCombo;
   private JLabel label;
   private static final int DEFAULT_SIZE = 24;
   public ComboBoxFrame()
   {
      // 添加示例文本标签
      label = new JLabel("The quick brown fox jumps over the lazy dog.");
      //设置字体
      label.setFont(new Font("Serif", Font.PLAIN, DEFAULT_SIZE));
      //添加到边框布局管理器的中间
      add(label, BorderLayout.CENTER);
      // 创建一个组合框对象并添加项目名称
      faceCombo = new JComboBox<>();
      //把一个选项添加到选项列表中，共五种选项
      faceCombo.addItem("Serif");
      faceCombo.addItem("SansSerif");
      faceCombo.addItem("Monospaced");
      faceCombo.addItem("Dialog");
      faceCombo.addItem("DialogInput");
      // 组合框监听器将标签字体更改为所选的名称（添加监听器，使用lambda表达式）
      faceCombo.addActionListener(event ->
      //设置标签的字体
         label.setFont(
            //getItemAt用于返回指定索引处的列表项；getSelectedIndex用于返回当前选择的选项
            new Font(faceCombo.getItemAt(faceCombo.getSelectedIndex()), 
               Font.PLAIN, DEFAULT_SIZE)));
      // 将组合框添加到框架南部边界的面板
      JPanel comboPanel = new JPanel();
      comboPanel.add(faceCombo);
      add(comboPanel, BorderLayout.SOUTH);
      pack();
   }
}
ComboBoxFrame

测试程序8

l 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；

l 掌握菜单的创建、菜单事件监听器、复选框和单选按钮菜单项、弹出菜单以及快捷键和加速器的用法。

l 记录示例代码阅读理解中存在的问题与疑惑。

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"));
      // demonstrate accelerators
      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);
            }
         });
      // demonstrate checkbox and radio button menus
      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);
      // demonstrate icons
      Action cutAction = new TestAction("Cut");
      cutAction.putValue(Action.SMALL_ICON, new ImageIcon("cut.gif"));
      Action copyAction = new TestAction("Copy");
      copyAction.putValue(Action.SMALL_ICON, new ImageIcon("copy.gif"));
      Action 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);
      // demonstrate nested menus
      JMenu optionMenu = new JMenu("Options");
      optionMenu.add(readonlyItem);
      optionMenu.addSeparator();
      optionMenu.add(insertItem);
      optionMenu.add(overtypeItem);
      editMenu.addSeparator();
      editMenu.add(optionMenu);
      // demonstrate mnemonics
      JMenu helpMenu = new JMenu("Help");
      helpMenu.setMnemonic('H');
      JMenuItem indexItem = new JMenuItem("Index");
      indexItem.setMnemonic('I');
      helpMenu.add(indexItem);
      // you can also add the mnemonic key to an action
      Action aboutAction = new TestAction("About");
      aboutAction.putValue(Action.MNEMONIC_KEY, new Integer('A'));
      helpMenu.add(aboutAction);
      
      // add all top-level menus to menu bar
      JMenuBar menuBar = new JMenuBar();
      setJMenuBar(menuBar);
      menuBar.add(fileMenu);
      menuBar.add(editMenu);
      menuBar.add(helpMenu);
      // demonstrate pop-ups
      popup = new JPopupMenu();
      popup.add(cutAction);
      popup.add(copyAction);
      popup.add(pasteAction);
      JPanel panel = new JPanel();
      panel.setComponentPopupMenu(popup);
      add(panel);
   }
}

package menu;
import java.awt.*;
import javax.swing.*;
/**
 * @version 1.24 2012-06-12
 * @author Cay Horstmann
 */
public class MenuTest
{
   public static void main(String[] args)
   {
      EventQueue.invokeLater(() -> {
         JFrame frame = new MenuFrame();
         frame.setTitle("MenuTest");
         frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
         frame.setVisible(true);
      });
   }
}

 

测试程序9

l 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；

l 掌握工具栏和工具提示的用法；

l 记录示例代码阅读理解中存在的问题与疑惑。

package toolBar;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
/**
 * A frame with a toolbar and menu for color changes.
 */
public class ToolBarFrame extends JFrame
{  //定义两个私有属性
   private static final int DEFAULT_WIDTH = 300;
   private static final int DEFAULT_HEIGHT = 200;
   private JPanel panel;
   public ToolBarFrame() //定义工具提示类
   {
      setSize(DEFAULT_WIDTH, DEFAULT_HEIGHT);
      // add a panel for color change
      panel = new JPanel();//创建新的JPanel
      add(panel, BorderLayout.CENTER);
      // set up actions
      //建立动作
      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");
      // populate toolbar
      JToolBar bar = new JToolBar();
      bar.add(blueAction);//用Action对象填充工具栏
      bar.add(yellowAction);
      bar.add(redAction);
      bar.addSeparator();//用分隔符将按钮分组
      bar.add(exitAction);
      add(bar, BorderLayout.NORTH);
      // populate menu
      JMenu menu = new JMenu("Color");//显示颜色的菜单
      menu.add(yellowAction);//在菜单添加颜色动作
      menu.add(blueAction);
      menu.add(redAction);
      menu.add(exitAction);
      JMenuBar menuBar = new JMenuBar();
      menuBar.add(menu);
      setJMenuBar(menuBar);
   }
   /**
    * The color action sets the background of the frame to a given color.
    */
   class ColorAction extends AbstractAction
   {
      public ColorAction(String name, Icon icon, Color c)
      {
         putValue(Action.NAME, name);//动作名称，显示在按钮和菜单
         putValue(Action.SMALL_ICON, icon);//存储小图标的地方；显示在按钮、菜单项或工具栏中
         putValue(Action.SHORT_DESCRIPTION, name + " background");
         putValue("Color", c);
      }
      public void actionPerformed(ActionEvent event)
      {
         Color c = (Color) getValue("Color");
         panel.setBackground(c);
      }
   }
}

测试程序10

l 在elipse IDE中调试运行教材524页程序12-10、12-11，结合运行结果理解程序，了解GridbagLayout的用法。

l 在elipse IDE中调试运行教材533页程序12-12，结合程序运行结果理解程序，了解GroupLayout的用法。

l 记录示例代码阅读理解中存在的问题与疑惑。

import java.awt.Font;
import java.awt.GridBagLayout;
import java.awt.event.ActionListener;
import javax.swing.BorderFactory;
import javax.swing.JCheckBox;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JTextArea;
/**
 * A frame that uses a grid bag layout to arrange font selection components.
 */
public class FontFrame extends JFrame
{
   public static final int TEXT_ROWS = 10;
   public static final int TEXT_COLUMNS = 20;
   private JComboBox<String> face;
   private JComboBox<Integer> size;
   private JCheckBox bold;
   private JCheckBox italic;
   private JTextArea sample;
   public FontFrame()
   {
      GridBagLayout layout = new GridBagLayout();
      setLayout(layout);
      ActionListener listener = event -> updateSample();
      // construct components
      JLabel faceLabel = new JLabel("Face: ");
      face = new JComboBox<>(new String[] { "Serif", "SansSerif", "Monospaced",
            "Dialog", "DialogInput" });
      face.addActionListener(listener);
      JLabel sizeLabel = new JLabel("Size: ");
      size = new JComboBox<>(new Integer[] { 8, 10, 12, 15, 18, 24, 36, 48 });
      size.addActionListener(listener);
      bold = new JCheckBox("Bold");
      bold.addActionListener(listener);
      italic = new JCheckBox("Italic");
      italic.addActionListener(listener);
      sample = new JTextArea(TEXT_ROWS, TEXT_COLUMNS);
      sample.setText("The quick brown fox jumps over the lazy dog");
      sample.setEditable(false);
      sample.setLineWrap(true);
      sample.setBorder(BorderFactory.createEtchedBorder());
      // add components to grid, using GBC convenience class
      add(faceLabel, new GBC(0, 0).setAnchor(GBC.EAST));
      add(face, new GBC(1, 0).setFill(GBC.HORIZONTAL).setWeight(100, 0)
            .setInsets(1));
      add(sizeLabel, new GBC(0, 1).setAnchor(GBC.EAST));
      add(size, new GBC(1, 1).setFill(GBC.HORIZONTAL).setWeight(100, 0)
            .setInsets(1));
      add(bold, new GBC(0, 2, 2, 1).setAnchor(GBC.CENTER).setWeight(100, 100));
      add(italic, new GBC(0, 3, 2, 1).setAnchor(GBC.CENTER).setWeight(100, 100));
      add(sample, new GBC(2, 0, 1, 4).setFill(GBC.BOTH).setWeight(100, 100));
      pack();
      updateSample();
   }
   public void updateSample()
   {
      String fontFace = (String) face.getSelectedItem();
      int fontStyle = (bold.isSelected() ? Font.BOLD : 0)
            + (italic.isSelected() ? Font.ITALIC : 0);
      int fontSize = size.getItemAt(size.getSelectedIndex());
      Font font = new Font(fontFace, fontStyle, fontSize);
      sample.setFont(font);
      sample.repaint();
   }
}

import java.awt.*;
/**
 * This class simplifies the use of the GridBagConstraints class.
 * @version 1.01 2004-05-06
 * @author Cay Horstmann
 */
public class GBC extends GridBagConstraints
{
   /**
    * Constructs a GBC with a given gridx and gridy position and all other grid
    * bag constraint values set to the default.
    * @param gridx the gridx position
    * @param gridy the gridy position
    */
   public GBC(int gridx, int gridy)
   {
      this.gridx = gridx;
      this.gridy = gridy;
   }
   /**
    * Constructs a GBC with given gridx, gridy, gridwidth, gridheight and all
    * other grid bag constraint values set to the default.
    * @param gridx the gridx position
    * @param gridy the gridy position
    * @param gridwidth the cell span in x-direction
    * @param gridheight the cell span in y-direction
    */
   public GBC(int gridx, int gridy, int gridwidth, int gridheight)
   {
      this.gridx = gridx;
      this.gridy = gridy;
      this.gridwidth = gridwidth;
      this.gridheight = gridheight;
   }
   /**
    * Sets the anchor.
    * @param anchor the anchor value
    * @return this object for further modification
    */
   public GBC setAnchor(int anchor)
   {
      this.anchor = anchor;
      return this;
   }
   /**
    * Sets the fill direction.
    * @param fill the fill direction
    * @return this object for further modification
    */
   public GBC setFill(int fill)
   {
      this.fill = fill;
      return this;
   }
   /**
    * Sets the cell weights.
    * @param weightx the cell weight in x-direction
    * @param weighty the cell weight in y-direction
    * @return this object for further modification
    */
   public GBC setWeight(double weightx, double weighty)
   {
      this.weightx = weightx;
      this.weighty = weighty;
      return this;
   }
   /**
    * Sets the insets of this cell.
    * @param distance the spacing to use in all directions
    * @return this object for further modification
    */
   public GBC setInsets(int distance)
   {
      this.insets = new Insets(distance, distance, distance, distance);
      return this;
   }
   /**
    * Sets the insets of this cell.
    * @param top the spacing to use on top
    * @param left the spacing to use to the left
    * @param bottom the spacing to use on the bottom
    * @param right the spacing to use to the right
    * @return this object for further modification
    */
   public GBC setInsets(int top, int left, int bottom, int right)
   {
      this.insets = new Insets(top, left, bottom, right);
      return this;
   }
   /**
    * Sets the internal padding
    * @param ipadx the internal padding in x-direction
    * @param ipady the internal padding in y-direction
    * @return this object for further modification
    */
   public GBC setIpad(int ipadx, int ipady)
   {
      this.ipadx = ipadx;
      this.ipady = ipady;
      return this;
   }
}

测试程序11

l 在elipse IDE中调试运行教材539页程序12-13、12-14，结合运行结果理解程序；

l 掌握定制布局管理器的用法。

l 记录示例代码阅读理解中存在的问题与疑惑。

测试程序12

l 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；

l 掌握选项对话框的用法。

l 记录示例代码阅读理解中存在的问题与疑惑。

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//对话框
{  //定义属性
   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);
   }
}

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);
      });
   }

测试程序13

l 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；

l 掌握对话框的创建方法；

l 记录示例代码阅读理解中存在的问题与疑惑。

package 课本示例13;
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 课本示例13;
import java.awt.*;
import java.awt.event.*;
import java.awt.geom.*;
import java.util.*;
import javax.swing.*;
/**
* 包含用于选择各种选项对话框的设置的框架。
*/
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;
}
/**
* 获取所选消息或选项类型
* @param面板消息类型或确认面板
* @return JOptionPane类中选定的XXX_MESSAGE或XXX_OPTION常量
*/
public int getType(ButtonPanel panel)
{
String s = panel.getSelection();
try
{
return JOptionPane.class.getField(s).getInt(null);
}
catch (Exception e)
{
return -1;
}
}
/**
* “显示”按钮的动作侦听器显示“确认”，“输入”，“消息”或“选项”对话框
*取决于“类型”面板选择。
*/
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]);
}
}
}
/**
* 具有涂漆表面的组件
*/
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);
}
}

package 课本示例13;

import javax.swing.*;

/**
 * 带标题边框内的单选按钮的面板.
 */
public class ButtonPanel extends JPanel
{
   private ButtonGroup group;

   /**
    * 构造一个按钮面板.
    * @param标题边框中显示的标题
    * @param选项一组单选按钮标签
    */
   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]);
      }
   }

   /**
    * 获取当前选定的选项。
    * @return当前所选单选按钮的标签。
    */
   public String getSelection()
   {
      return group.getSelection().getActionCommand();
   }
}

测试程序14

l 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；

l 掌握对话框的数据交换用法;

l 记录示例代码阅读理解中存在的问题与疑惑。

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()
   {
      // construct a File menu
      JMenuBar mbar = new JMenuBar();
      setJMenuBar(mbar);
      JMenu fileMenu = new JMenu("File");
      mbar.add(fileMenu);
      // add Connect and Exit menu items
      JMenuItem connectItem = new JMenuItem("Connect");
      connectItem.addActionListener(new ConnectAction());
      fileMenu.add(connectItem);
      // The Exit item exits the program
      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)
      {
         // if first time, construct dialog
         if (dialog == null) dialog = new PasswordChooser();
         // set default values
         dialog.setUser(new User("yourname", null));
         // pop up dialog
         if (dialog.showDialog(DataExchangeFrame.this, "Connect"))
         {
            // if accepted, retrieve user input
            User u = dialog.getUser();
            textArea.append("user name = " + u.getName() + ", password = "
                  + (new String(u.getPassword())) + "
");
         }
      }
   }
}

 

测试程序15

l 在elipse IDE中调试运行教材556页程序12-21、12-2212-23，结合程序运行结果理解程序；

l 掌握文件对话框的用法;

l 记录示例代码阅读理解中存在的问题与疑惑。

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()
   {
      // construct a File menu
      JMenuBar mbar = new JMenuBar();
      setJMenuBar(mbar);
      JMenu fileMenu = new JMenu("File");
      mbar.add(fileMenu);
      // add Connect and Exit menu items
      JMenuItem connectItem = new JMenuItem("Connect");
      connectItem.addActionListener(new ConnectAction());
      fileMenu.add(connectItem);
      // The Exit item exits the program
      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)
      {
         // if first time, construct dialog
         if (dialog == null) dialog = new PasswordChooser();
         // set default values
         dialog.setUser(new User("yourname", null));
         // pop up dialog
         if (dialog.showDialog(DataExchangeFrame.this, "Connect"))
         {
            // if accepted, retrieve user input
            User u = dialog.getUser();
            textArea.append("user name = " + u.getName() + ", password = "
                  + (new String(u.getPassword())) + "
");
         }
      }
   }
}

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());
      // construct a panel with user name and password fields
      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);
      // create Ok and Cancel buttons that terminate the dialog
      okButton = new JButton("Ok");
      okButton.addActionListener(event -> {
         ok = true;
         dialog.setVisible(false);
      });
      JButton cancelButton = new JButton("Cancel");
      cancelButton.addActionListener(event -> dialog.setVisible(false));
      // add buttons to southern border
      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;
      // locate the owner frame
      Frame owner = null;
      if (parent instanceof Frame)
         owner = (Frame) parent;
      else
         owner = (Frame) SwingUtilities.getAncestorOfClass(Frame.class, parent);
      // if first time, or if owner has changed, make new dialog
      if (dialog == null || dialog.getOwner() != owner)
      {
         dialog = new JDialog(owner, true);
         dialog.add(this);
         dialog.getRootPane().setDefaultButton(okButton);
         dialog.pack();
      }
      // set title and show dialog
      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;
   }
}

测试程序16

l 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；

l 了解颜色选择器的用法。

记录示例代码阅读理解中存在的问题与疑惑。

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()//狗仔一个初始颜色的颜色选择器
   {
      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 javax.swing.*;
/**
 * A frame with a color chooser panel
 */
public class ColorChooserFrame extends JFrame
{//设置两个私有属性
   private static final int DEFAULT_WIDTH = 300;
   private static final int DEFAULT_HEIGHT = 200;
   public ColorChooserFrame()//颜色选择器
   {      
      setSize(DEFAULT_WIDTH, DEFAULT_HEIGHT);
      // add color chooser panel to frame
      ColorChooserPanel panel = new ColorChooserPanel();
      add(panel);
   }
}

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();//生成ColorChooserFrame类
         frame.setTitle("ColorChooserTest");
         frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);//关闭界面操作
         frame.setVisible(true);
      });
   }
}

实验2：组内讨论反思本组负责程序，理解程序总体结构，梳理程序GUI设计中应用的相关组件，整理相关组件的API,对程序中组件应用的相关代码添加注释。

所添加注释：

package 课本示例13;

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 课本示例13;

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

/**
* 包含用于选择各种选项对话框的设置的框架。
*/
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;
}

/**
* 获取所选消息或选项类型
* @param面板消息类型或确认面板
* @return JOptionPane类中选定的XXX_MESSAGE或XXX_OPTION常量
*/
public int getType(ButtonPanel panel)
{
String s = panel.getSelection();
try
{
return JOptionPane.class.getField(s).getInt(null);
}
catch (Exception e)
{
return -1;
}
}

/**
* “显示”按钮的动作侦听器显示“确认”，“输入”，“消息”或“选项”对话框
*取决于“类型”面板选择。
*/
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]);
}
}
}

/**
* 具有涂漆表面的组件
*/

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);
}
}

package 课本示例13;

import javax.swing.*;

/**

 * 带标题边框内的单选按钮的面板.

 */

public class ButtonPanel extends JPanel

{

   private ButtonGroup group;

   /**

    * 构造一个按钮面板.

    * @param标题边框中显示的标题

    * @param选项一组单选按钮标签

    */

   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]);

      }

   }

   /**

    * 获取当前选定的选项。

    * @return当前所选单选按钮的标签。

    */

   public String getSelection()

   {

      return group.getSelection().getActionCommand();

   }

}

GUI相关组件： 

GUI窗口

　　Jframe是窗体组件。创建该组件即创建了一个窗口。窗口是一个容器组件，所有内容均可以放入其中。

　　创建窗体对象：

　　JFrame frame = newJFrame(“标题”);

　　// 在这里需要简单设置属性:

　　frame.setSize(int 宽,int 高); //设置窗体尺寸

　　frame.setLocation(int x轴，int y轴); //设置窗体位置

　　frame. setVisible(true); //设置窗体可见

　　this.setResizable(false); //设置窗体大小固定

　　this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);// 关闭窗口默认操作

　　向窗体中添加其他组件：

　　frame.add(其他组件);

GUI布局

　　布局是指界面存放组件位置的方式。

　　如果组件凌乱地存放在容器当中不好看，通常可以采用对应布局方式，来规范组件的位置,Java也提供了常见的布局对象。

　　LayoutManager： 布局接口，各种布局类均为其子类

　　frame.setLayout(布局对象) //设置窗口布局

　　null：不使用布局，此时可以容器内的组件可以调用方法，通过坐标以及尺寸进行组件定位：

　　组件定位方法为void setBounds(int x轴，int y轴，int 宽度，int 高度)

　　BorderLayout：边界布局，将界面分为东西南北中5个方位，frame的默认布局

　　GUI面板

　　JPanel面板与JFrame窗体类似，属于容器组件，可以存放其他组件内容。通常用来划分区域，完成一个完整的功能。

　　通常的方式是： JFrame存放JPanel，JPanel存放其他组件。

　　GUI按钮

　　在容器内最终完成数据展示与交互的均为功能组件。组件众多，其他组件的使用方法均类似，这里不一一介绍。欢迎界面中使用到了Button组件。

　　Button btn = new Button();

　　通用步骤：

　　1、创建功能组件对象;

　　2、给功能组件绑定监听器;

　　3、将功能组件添加到容器组件中;

　　 GUI监听器

　　页面中的各种组件均包含一些Java预设的用户操作(如鼠标点击，键盘按键等)，如何在用户完成对应操作时，执行对应的代码，是事件监听机制完成的。

　　将发生预设事件的组件绑定监听器，监听器某个组件是否发生了用户操作，当用户进行对应的操作后，执行对应代码。

　　我们最常见的操作是鼠标点击按钮，是按钮的动作。这里介绍按钮的事件监听。

　　事件监听步骤：

　　① 被监听的组件调用方法与监听器关联

　　按钮组件关联监听器方法：addActionListener(监听器对象)

　　按钮动作监听器接口：ActionListener

　　② 在监听器中定义用户操作对应的执行代码

实验3：组间协同学习：在本班课程QQ群内，各位同学对实验1中存在的问题进行提问，提问时注明实验1中的测试程序编号，负责对应程序的小组需及时对群内提问进行回答。

实验总结：

1. Swing简介

 Swing 是 Java 为图形界面应用开发提供的一组工具包，是 Java 基础类的一部分。

 Swing 包含了构建图形界面（GUI）的各种组件，如: 窗口、标签、按钮、文本框等。

 Swing 提供了许多比 AWT 更好的屏幕显示元素，使用纯 Java 实现，能够更好的兼容跨平台运行。

 为了和AWT 组件区分，Swing 组件在javax.swing.*包下，类名均以 J 开头，例如: JFrame、JLabel、JButton等。

 2. Swing组件

 一个Java 的图形界面，由各种不同类型的“元素”组成，例如: 窗口、菜单栏、对话框、标签、按钮、文本框等等，这些“元素”统一被称为 组件（Component）。

 组件按照不同的功能，可分为顶层容器、中间容器、基本组件。一个简单窗口的组成，如下层级结构所示:

 顶层容器

菜单栏

中间容器

基本组件

基本组件

组件类型的继承关系:

 

顶层容器属于窗口类组件，继承自java.awt.Window；

中间容器和基本组件继承自javax.swing.JComponent。

（1）顶层容器

 

顶层容器属于窗口类组件，可以独立显示，一个图形界面至少需要一个窗口，例如:

 

#组件描述

1JFrame一个普通的窗口（绝大多数Swing 图形界面程序使用 JFrame 作为顶层容器）

2JDialog对话框

（2）中间容器

 中间容器充当基本组件的载体，不可独立显示。中间容器可以添加若干基本组件（也可以嵌套添加中间容器），对容器内的组件进行管理，类似于给各种复杂的组件进行分组管理。最顶层的一个中间容器必须依托在顶层容器（窗口）内。

 常用的中间容器（面板）:

 #组件描述

1JPanel一般轻量级面板容器组件

2JScrollPane带滚动条的，可以水平和垂直滚动的面板组件

3JSplitPane分隔面板

4JTabbedPane选项卡面板

5JLayeredPane层级面板

 

特殊的中间容器:

#组件描述

1JMenuBar菜单栏

2JToolBar工具栏

3JPopupMenu弹出菜单

4JInternalFrame内部窗口

 

（3）基本组件

 

基本组件是直接实现人机交互的组件。

 常用的简单的基本组件:

 #组件描述

1JLabel标签

2JButton按钮

3JRadioButton单选按钮

4JCheckBox复选框

5JToggleButton开关按钮

6JTextField文本框

7JPasswordField密码框

8JTextArea文本区域

9JComboBox下拉列表框

10JList列表

11JProgressBar进度条

12JSlider滑块

 

选取器组件:

#组件描述

1JFileChooser文件选取器

2JColorChooser颜色选取器

 

其他较为复杂的基本组件:

#组件描述

1JTable表格

2JTree树

3. 布局管理器

 把Swing 的各种组件(JComponent)添加到面板容器中(JPanel)，需要给面板容器指定布局管理器(LayoutManager)，明确容器(Container)内的各个组件之间的排列布局方式。

 常用的布局管理器:

 #布局管理器描述

1FlowLayout流式布局，按组件加入的顺序，按水平方向排列，排满一行换下一行继续排列。

2GridLayout网格布局，把Container按指定行列数分隔出若干网格，每一个网格按顺序放置一个控件。

3GridBagLayout网格袋布局，按网格划分Container，每个组件可占用一个或多个网格，可将组件垂直、水平或沿它们的基线对齐。

4BoxLayout箱式布局，将Container中的多个组件按 水平 或 垂直 的方式排列。

5GroupLayout分组布局，将组件按层次分组（串行或并行），分别确定组件组在水平和垂直方向上的位置。

6CardLayout卡片布局，将Container中的每个组件看作一张卡片，一次只能显示一张卡片，默认显示第一张卡片。

7BorderLayout边界布局，把Container按方位分为 5 个区域（东、西、南、北、中），每个区域放置一个组件。

8SpringLayout弹性布局，通过定义组件四条边的坐标位置来实现布局。

9null绝对布局，通过设置组件在Container中的坐标位置来放置组件。

4. 代码实例: 一个简单的窗口程序

 

package com.xiets.swing;

 

import javax.swing.*;

 

public class Main {

 

    public static void main(String[] args) {

        // 1. 创建一个顶层容器（窗口）

        JFrame jf = new JFrame("测试窗口");          // 创建窗口

        jf.setSize(250, 250);                       // 设置窗口大小

        jf.setLocationRelativeTo(null);             // 把窗口位置设置到屏幕中心

        jf.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE); // 当点击窗口的关闭按钮时退出程序（没有这一句，程序不会退出）

 

        // 2. 创建中间容器（面板容器）

        JPanel panel = new JPanel();                // 创建面板容器，使用默认的布局管理器

 

        // 3. 创建一个基本组件（按钮），并添加到 面板容器 中

        JButton btn = new JButton("测试按钮");

        panel.add(btn);

 

        // 4. 把 面板容器 作为窗口的内容面板 设置到 窗口

        jf.setContentPane(panel);

 

        // 5. 显示窗口，前面创建的信息都在内存中，通过 jf.setVisible(true) 把内存中的窗口显示在屏幕上。

        jf.setVisible(true);

    }

 

}