王颖奇 20171010129《面向对象程序设计（java）》第十四周学习总结

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王颖奇 20171010129《面向对象程序设计（java）》第十四周学习总结

阅读原文时间：2023年07月15日阅读：3

实验十四 Swing图形界面组件

理论知识知识点：

1.Swing和MVC设计模式
2.布局管理器
3.文本输入
4.选择组件
5.菜单
6.对话框

实验时间 2018-11-29

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

/**
* 带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()
{
//为容器设置布局管理器，为边框布局管理器
setLayout(new BorderLayout());

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

  // 添加页面显示

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

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

  // 在4\*4的网格中添加按钮

  panel = new JPanel();  
  //在panel对象中设置边框布局管理器  
  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);

}

/**
* 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);
}

/**
* 此操作将按钮操作的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();
if (start)
{
display.setText("");
start = false;
}
display.setText(display.getText() + input);
}
}

/**
* 该操作执行按钮操作的字符串表示的命令。
*/
private class CommandAction implements ActionListener
{
public void actionPerformed(ActionEvent event)
{
String command = event.getActionCommand();

     if (start)  
     {  
        if (command.equals("-"))  
        {  
           display.setText(command);  
           start = false;  
        }  
        else lastCommand = command;  
     }  
     else  
     {  
        calculate(Double.parseDouble(display.getText()));  
        lastCommand = command;  
        start = true;  
     }  
  }

}

/**
* 具体的计算
* @param x与先前结果累积的值。
*/
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;
//将结果转化成字符串显示
display.setText("" + result);
}
}

CalculatorPanel

运行结果：

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。

代码：

package text;

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

/**
* @version 1.41 2015-06-12
* @author Cay Horstmann
*/
public class TextComponentTest
{
public static void main(String[] args)
{
EventQueue.invokeLater(() -> {
JFrame frame = new TextComponentFrame();
frame.setTitle("TextComponentTest");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
});
}
}

TextComponentTest

package text;

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;

/**
* 带有输入文本框组件的框架。
*/
public class TextComponentFrame extends JFrame
{
public static final int TEXTAREA_ROWS = 8;
public static final int TEXTAREA_COLUMNS = 20;

public TextComponentFrame()
{
JTextField textField = new JTextField();
JPasswordField passwordField = new JPasswordField();

  JPanel northPanel = new JPanel();  
  northPanel.setLayout(new GridLayout(2, 2));  
  //SwingConstants通常用于在屏幕上定位或定向组件的常量的集合  
  northPanel.add(new JLabel("User name: ", SwingConstants.RIGHT));  
  northPanel.add(textField);  
  northPanel.add(new JLabel("Password: ", SwingConstants.RIGHT));  
  northPanel.add(passwordField);

  add(northPanel, BorderLayout.NORTH);

  //构造具有指定行数和列数的新的空 TextArea。  
  JTextArea textArea = new JTextArea(TEXTAREA\_ROWS, TEXTAREA\_COLUMNS);  
  //创建一个显示指定组件内容的 JScrollPane对象，只要组件的内容超过视图大小就会显示水平和垂直滚动条。  
  JScrollPane scrollPane = new JScrollPane(textArea);

  add(scrollPane, BorderLayout.CENTER);

  // add button to append text into the text area

  JPanel southPanel = new JPanel();

  JButton insertButton = new JButton("Insert");  
  southPanel.add(insertButton);  
  //将给定文本追加到文档结尾。  
  insertButton.addActionListener(event ->  
     textArea.append("User name: " + textField.getText() + " Password: "  
        + new String(passwordField.getPassword()) + "\\n"));

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

}
}

TextComponentFrame

运行结果：

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。

代码：

package checkBox;

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 checkBox;

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()
{
// 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);

  // 字体属性  
  // 复选框状态的标签

  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

运行结果：

普通字体：加粗：

斜体和加粗：斜体：

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。

代码：

package radioButton;

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 radioButton;

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

/**
* 带有示例文本标签和用于选择字体大小的单选按钮的框架。
*/
public class RadioButtonFrame extends JFrame
{
private JPanel buttonPanel;
private ButtonGroup group;
private JLabel label;
private static final int DEFAULT_SIZE = 36;

public RadioButtonFrame()
{
// add the sample text label

  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);

  // add the radio buttons

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

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

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

}

/**
* 添加一个单选按钮，用于设置示例文本的字体大小。
* @param 大小的规格要出现在按钮上的字符串
* @param 按钮设置的字体大小
*/
public void addRadioButton(String name, int size)
{
boolean selected = size == DEFAULT_SIZE;
JRadioButton button = new JRadioButton(name, selected);
group.add(button);
buttonPanel.add(button);

  // 此监听器设置标签字体大小

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

  button.addActionListener(listener);

}
}

RadioButtonFrame

运行结果：

samll：

medium：

large：

extra large：

单选钮，只能选中一个

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。

代码：

package border;

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 border;

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();

  //设置不同的边框类型按钮，共六种（提供标准 Border 对象的工厂类）  
  addRadioButton("Lowered bevel", BorderFactory.createLoweredBevelBorder());  
  addRadioButton("Raised bevel", BorderFactory.createRaisedBevelBorder());  
  addRadioButton("Etched", BorderFactory.createEtchedBorder());  
  addRadioButton("Line", BorderFactory.createLineBorder(Color.BLUE));  
  addRadioButton("Matte", BorderFactory.createMatteBorder(10, 10, 10, 10, Color.BLUE));  
  addRadioButton("Empty", BorderFactory.createEmptyBorder());

  Border etched = BorderFactory.createEtchedBorder();  
  Border titled = BorderFactory.createTitledBorder(etched, "Border types");  
  buttonPanel.setBorder(titled);

  setLayout(new GridLayout(2, 1));  
  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

运行结果：

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。

本小组负责的示例程序（如有问题与疑惑，请看注释）：

代码：

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);
});
}
}

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 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();

}
}

运行结果：

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。

代码：

package slider;

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

/**
* @version 1.15 2015-06-12
* @author Cay Horstmann
*/
public class SliderTest
{
public static void main(String[] args)
{
EventQueue.invokeLater(() -> {
SliderFrame frame = new SliderFrame();
frame.setTitle("SliderTest");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
});
}
}

SliderTest

package slider;

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

/**
* A frame with many sliders and a text field to show slider values.
*/
public class SliderFrame extends JFrame
{
private JPanel sliderPanel;
private JTextField textField;
private ChangeListener listener;

public SliderFrame()
{
sliderPanel = new JPanel();
sliderPanel.setLayout(new GridBagLayout());

  // common listener for all sliders  
  listener = event -> {  
     // update text field when the slider value changes  
     JSlider source = (JSlider) event.getSource();  
     textField.setText("" + source.getValue());  
  };

  // add a plain slider

  JSlider slider = new JSlider();  
  addSlider(slider, "Plain");

  // add a slider with major and minor ticks

  slider = new JSlider();  
  slider.setPaintTicks(true);  
  slider.setMajorTickSpacing(20);  
  slider.setMinorTickSpacing(5);  
  addSlider(slider, "Ticks");

  // add a slider that snaps to ticks

  slider = new JSlider();  
  slider.setPaintTicks(true);  
  slider.setSnapToTicks(true);  
  slider.setMajorTickSpacing(20);  
  slider.setMinorTickSpacing(5);  
  addSlider(slider, "Snap to ticks");

  // add a slider with no track

  slider = new JSlider();  
  slider.setPaintTicks(true);  
  slider.setMajorTickSpacing(20);  
  slider.setMinorTickSpacing(5);  
  slider.setPaintTrack(false);  
  addSlider(slider, "No track");

  // add an inverted slider

  slider = new JSlider();  
  slider.setPaintTicks(true);  
  slider.setMajorTickSpacing(20);  
  slider.setMinorTickSpacing(5);  
  slider.setInverted(true);  
  addSlider(slider, "Inverted");

  // add a slider with numeric labels

  slider = new JSlider();  
  slider.setPaintTicks(true);  
  slider.setPaintLabels(true);  
  slider.setMajorTickSpacing(20);  
  slider.setMinorTickSpacing(5);  
  addSlider(slider, "Labels");

  // add a slider with alphabetic labels

  slider = new JSlider();  
  slider.setPaintLabels(true);  
  slider.setPaintTicks(true);  
  slider.setMajorTickSpacing(20);  
  slider.setMinorTickSpacing(5);

  Dictionary<Integer, Component> labelTable = new Hashtable<>();  
  labelTable.put(0, new JLabel("A"));  
  labelTable.put(20, new JLabel("B"));  
  labelTable.put(40, new JLabel("C"));  
  labelTable.put(60, new JLabel("D"));  
  labelTable.put(80, new JLabel("E"));  
  labelTable.put(100, new JLabel("F"));

  slider.setLabelTable(labelTable);  
  addSlider(slider, "Custom labels");

  // add a slider with icon labels

  slider = new JSlider();  
  slider.setPaintTicks(true);  
  slider.setPaintLabels(true);  
  slider.setSnapToTicks(true);  
  slider.setMajorTickSpacing(20);  
  slider.setMinorTickSpacing(20);

  labelTable = new Hashtable<Integer, Component>();

  // add card images

  labelTable.put(0, new JLabel(new ImageIcon("nine.gif")));  
  labelTable.put(20, new JLabel(new ImageIcon("ten.gif")));  
  labelTable.put(40, new JLabel(new ImageIcon("jack.gif")));  
  labelTable.put(60, new JLabel(new ImageIcon("queen.gif")));  
  labelTable.put(80, new JLabel(new ImageIcon("king.gif")));  
  labelTable.put(100, new JLabel(new ImageIcon("ace.gif")));

  slider.setLabelTable(labelTable);  
  addSlider(slider, "Icon labels");

  // add the text field that displays the slider value

  textField = new JTextField();  
  add(sliderPanel, BorderLayout.CENTER);  
  add(textField, BorderLayout.SOUTH);  
  pack();

}

/**
* Adds a slider to the slider panel and hooks up the listener
* @param s the slider
* @param description the slider description
*/
public void addSlider(JSlider s, String description)
{
s.addChangeListener(listener);
JPanel panel = new JPanel();
panel.add(s);
panel.add(new JLabel(description));
panel.setAlignmentX(Component.LEFT_ALIGNMENT);
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridy = sliderPanel.getComponentCount();
gbc.anchor = GridBagConstraints.WEST;
sliderPanel.add(panel, gbc);
}
}

SliderFrame

运行结果：

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。

代码：

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);
});
}
}

MenuTest

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);  
}

}

MenuFrame

运行结果：

三个主菜单：

1.点击Exit会关闭窗口

2.使用快捷键Ctrl+O和Ctrl+S，操作结果与鼠标点击相同：

控制台上显示：

3.Options子菜单（复选框和单选按钮菜单项）

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。

代码：

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);
});
}
}

ToolBarTest

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
{
private static final int DEFAULT_WIDTH = 300;
private static final int DEFAULT_HEIGHT = 200;
private JPanel panel;

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

  // add a panel for color change

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

  // set up actions

  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);  
  bar.add(yellowAction);  
  bar.add(redAction);  
  bar.addSeparator();  
  bar.add(exitAction);  
  add(bar, BorderLayout.NORTH);

  // populate menu

  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);

}

/**
* 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);
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);  
  }

}
}

ToolBarFrame

运行结果：

初始：

分别点击四个按钮之后：

将鼠标放置在四个按钮上都会有对应的提示(如图）:

问题与疑惑：

1.此段代码中：putValue的使用意义和使用方法

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);
      }
   }

2.蓝色球前面有一些细小的点是怎么设置的

测试程序10到12有较多不懂的地方：

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。

代码：

GridBag：

package gridbag;

import java.awt.EventQueue;

import javax.swing.JFrame;

/**
* @version 1.35 2015-06-12
* @author Cay Horstmann
*/
public class GridBagLayoutTest
{
public static void main(String[] args)
{
EventQueue.invokeLater(() -> {
JFrame frame = new FontFrame();
frame.setTitle("GridBagLayoutTest");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
});
}
}

GridBagLayoutTest

package gridbag;

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;
}
}

GBC

package gridbag;

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 face;
private JComboBox 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();
}
}

FontFrame

Group：

package groupLayout;

import java.awt.EventQueue;

import javax.swing.JFrame;

/**
* @version 1.01 2015-06-12
* @author Cay Horstmann
*/
public class GroupLayoutTest
{
public static void main(String[] args)
{
EventQueue.invokeLater(() -> {
JFrame frame = new FontFrame();
frame.setTitle("GroupLayoutTest");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
});
}
}

GroupLayoutTest

package groupLayout;

import java.awt.Font;
import java.awt.event.ActionListener;

import javax.swing.BorderFactory;
import javax.swing.GroupLayout;
import javax.swing.JCheckBox;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.LayoutStyle;
import javax.swing.SwingConstants;

/**
* A frame that uses a group 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 face;
private JComboBox size;
private JCheckBox bold;
private JCheckBox italic;
private JScrollPane pane;
private JTextArea sample;

public FontFrame()
{
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());

  pane = new JScrollPane(sample);

  GroupLayout layout = new GroupLayout(getContentPane());  
  setLayout(layout);  
  layout.setHorizontalGroup(layout.createParallelGroup(GroupLayout.Alignment.LEADING)  
        .addGroup(  
              layout.createSequentialGroup().addContainerGap().addGroup(  
                    layout.createParallelGroup(GroupLayout.Alignment.LEADING).addGroup(  
                          GroupLayout.Alignment.TRAILING,  
                          layout.createSequentialGroup().addGroup(  
                                layout.createParallelGroup(GroupLayout.Alignment.TRAILING)  
                                      .addComponent(faceLabel).addComponent(sizeLabel))  
                                .addPreferredGap(LayoutStyle.ComponentPlacement.RELATED)  
                                .addGroup(  
                                      layout.createParallelGroup(  
                                            GroupLayout.Alignment.LEADING, false)  
                                            .addComponent(size).addComponent(face)))  
                          .addComponent(italic).addComponent(bold)).addPreferredGap(  
                    LayoutStyle.ComponentPlacement.RELATED).addComponent(pane)  
                    .addContainerGap()));

  layout.linkSize(SwingConstants.HORIZONTAL, new java.awt.Component\[\] { face, size });

  layout.setVerticalGroup(layout.createParallelGroup(GroupLayout.Alignment.LEADING)  
        .addGroup(  
              layout.createSequentialGroup().addContainerGap().addGroup(  
                    layout.createParallelGroup(GroupLayout.Alignment.LEADING).addComponent(  
                          pane, GroupLayout.Alignment.TRAILING).addGroup(  
                          layout.createSequentialGroup().addGroup(  
                                layout.createParallelGroup(GroupLayout.Alignment.BASELINE)  
                                      .addComponent(face).addComponent(faceLabel))  
                                .addPreferredGap(LayoutStyle.ComponentPlacement.RELATED)  
                                .addGroup(  
                                      layout.createParallelGroup(  
                                            GroupLayout.Alignment.BASELINE).addComponent(size)  
                                            .addComponent(sizeLabel)).addPreferredGap(  
                                      LayoutStyle.ComponentPlacement.RELATED).addComponent(  
                                      italic, GroupLayout.DEFAULT\_SIZE,  
                                      GroupLayout.DEFAULT\_SIZE, Short.MAX\_VALUE)  
                                .addPreferredGap(LayoutStyle.ComponentPlacement.RELATED)  
                                .addComponent(bold, GroupLayout.DEFAULT\_SIZE,  
                                      GroupLayout.DEFAULT\_SIZE, Short.MAX\_VALUE)))  
                    .addContainerGap()));  
  pack();

}

FontFrame

运行结果：

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。

代码：

package circleLayout;

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

/**
* @version 1.33 2015-06-12
* @author Cay Horstmann
*/
public class CircleLayoutTest
{
public static void main(String[] args)
{
EventQueue.invokeLater(() -> {
JFrame frame = new CircleLayoutFrame();
frame.setTitle("CircleLayoutTest");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
});
}
}

CircleLayoutTest

package circleLayout;

import java.awt.*;

/**
* A layout manager that lays out components along a circle.
*/
public class CircleLayout implements LayoutManager
{
private int minWidth = 0;
private int minHeight = 0;
private int preferredWidth = 0;
private int preferredHeight = 0;
private boolean sizesSet = false;
private int maxComponentWidth = 0;
private int maxComponentHeight = 0;

public void addLayoutComponent(String name, Component comp)
{
}

public void removeLayoutComponent(Component comp)
{
}

public void setSizes(Container parent)
{
if (sizesSet) return;
int n = parent.getComponentCount();

  preferredWidth = 0;  
  preferredHeight = 0;  
  minWidth = 0;  
  minHeight = 0;  
  maxComponentWidth = 0;  
  maxComponentHeight = 0;

  // compute the maximum component widths and heights  
  // and set the preferred size to the sum of the component sizes.  
  for (int i = 0; i < n; i++)  
  {  
     Component c = parent.getComponent(i);  
     if (c.isVisible())  
     {  
        Dimension d = c.getPreferredSize();  
        maxComponentWidth = Math.max(maxComponentWidth, d.width);  
        maxComponentHeight = Math.max(maxComponentHeight, d.height);  
        preferredWidth += d.width;  
        preferredHeight += d.height;  
     }  
  }  
  minWidth = preferredWidth / 2;  
  minHeight = preferredHeight / 2;  
  sizesSet = true;

}

public Dimension preferredLayoutSize(Container parent)
{
setSizes(parent);
Insets insets = parent.getInsets();
int width = preferredWidth + insets.left + insets.right;
int height = preferredHeight + insets.top + insets.bottom;
return new Dimension(width, height);
}

public Dimension minimumLayoutSize(Container parent)
{
setSizes(parent);
Insets insets = parent.getInsets();
int width = minWidth + insets.left + insets.right;
int height = minHeight + insets.top + insets.bottom;
return new Dimension(width, height);
}

public void layoutContainer(Container parent)
{
setSizes(parent);

  // compute center of the circle

  Insets insets = parent.getInsets();  
  int containerWidth = parent.getSize().width - insets.left - insets.right;  
  int containerHeight = parent.getSize().height - insets.top - insets.bottom;

  int xcenter = insets.left + containerWidth / 2;  
  int ycenter = insets.top + containerHeight / 2;

  // compute radius of the circle

  int xradius = (containerWidth - maxComponentWidth) / 2;  
  int yradius = (containerHeight - maxComponentHeight) / 2;  
  int radius = Math.min(xradius, yradius);

  // lay out components along the circle

  int n = parent.getComponentCount();  
  for (int i = 0; i < n; i++)  
  {  
     Component c = parent.getComponent(i);  
     if (c.isVisible())  
     {  
        double angle = 2 \* Math.PI \* i / n;

        // center point of component  
        int x = xcenter + (int) (Math.cos(angle) \* radius);  
        int y = ycenter + (int) (Math.sin(angle) \* radius);

        // move component so that its center is (x, y)  
        // and its size is its preferred size  
        Dimension d = c.getPreferredSize();  
        c.setBounds(x - d.width / 2, y - d.height / 2, d.width, d.height);  
     }  
  }

}
}

CircleLayout

package circleLayout;

import javax.swing.*;

/**
* A frame that shows buttons arranged along a circle.
*/
public class CircleLayoutFrame extends JFrame
{
public CircleLayoutFrame()
{
setLayout(new CircleLayout());
add(new JButton("Yellow"));
add(new JButton("Blue"));
add(new JButton("Red"));
add(new JButton("Green"));
add(new JButton("Orange"));
add(new JButton("Fuchsia"));
add(new JButton("Indigo"));
pack();
}
}

CircleLayoutFrame

运行结果：

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。

代码：

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);
});
}
}

OptionDialogTest

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();
}
}

ButtonPanel

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);
}
}

OptionDialogFrame

运行结果：

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。

代码：

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);
});
}
}

DialogTest

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);

}
}

DialogFrame

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();

}
}

AboutDialog

运行结果：

点击About后：

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。

代码：

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);
});
}
}

DataExchangeTest

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())) + "\\n");  
     }  
  }

}
}

DataExchangeFrame

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;

}
}

PasswordChooser

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;
}
}

User

运行结果：