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(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

elipse IDE中运行教材479页程序12-1,结合运行结果理解程序;

掌握各种布局管理器的用法;

理解GUI界面中事件处理技术的用途。

在布局管理应用代码处添加注释;

package calculator;

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

/**
 * A panel with calculator buttons and a result display.
 */
public class CalculatorPanel extends JPanel
{
    //定义了五个对象
   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;

      // add the display

      display = new JButton("0");// display用来显示一个算法的结果
      display.setEnabled(false);
      add(display, BorderLayout.NORTH);
      //定义了两个监听器对象
      ActionListener insert = new InsertAction();
      ActionListener command = new CommandAction();

      // add the buttons in a 4 x 4 grid

      panel = new JPanel();//容器组件
      panel.setLayout(new GridLayout(4, 4));//四行四列的网格
     //调用addButton方法来添加按钮
      addButton("3", insert);
      addButton("6", insert);
      addButton("9", insert);
      addButton("/", command);

      addButton("2", insert);
      addButton("5", insert);
      addButton("8", insert);
      addButton("*", command);

      addButton("1", insert);
      addButton("4", insert);
      addButton("7", insert);
      addButton("-", command);

      addButton("0", insert);
      addButton(".", insert);
      addButton("=", command);
      addButton("+", command);
      //创建了16个事件源

      add(panel, BorderLayout.SOUTH);

       JButton b1 = new JButton("验证");
      add(b1, BorderLayout.SOUTH);


   }

   /**
    * Adds a button to the center panel.
    * @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);
   }

   /**
    * This action inserts the button action string to the end of the display text.
    */
   private class InsertAction implements ActionListener
   {
      public void actionPerformed(ActionEvent event)
      {
         String input = event.getActionCommand();//通过事件源来获得动作
         if (start)
         {
            display.setText("");//用setText方法 来更改
            start = false;
         }
         display.setText(display.getText() + input);
      }
   }

   /**
    * This action executes the command that the button action string denotes.
    */
   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()));
            //将数字字符串转换成对应的数字,用parseDouble
            lastCommand = command;//控制变量
            start = true;
         }
      }
   }

   /**
    * Carries out the pending calculation.
    * @param x the value to be accumulated with the prior result.
    */
   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);//""的意义在于字符串的转换
   }
}

package calculator;

import javax.swing.*;

/**
 * A frame with a calculator panel.
 */
public class CalculatorFrame extends JFrame
{
   public CalculatorFrame()
   {
      add(new CalculatorPanel());
      pack();//用pack方法
   }
}
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);////关闭界面的按钮操作
         frame.setVisible(true);//可见的
      });
   }
}

 

测试程序2

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;

掌握各种文本组件的用法;

记录示例代码阅读理解中存在的问题与疑惑。

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;

/**
 * A frame with sample text components.
 */
public class TextComponentFrame extends JFrame
{  //定义网格的行数、列数
   public static final int TEXTAREA_ROWS = 8;
   public static final int TEXTAREA_COLUMNS = 20;

   public TextComponentFrame()
   {
      JTextField textField = new JTextField();//创建一个新的文本域
      JPasswordField passwordField = new JPasswordField();

      JPanel northPanel = new JPanel();//构造一个JPanel组件
      northPanel.setLayout(new GridLayout(2, 2));//设置布局管理器
      northPanel.add(new JLabel("User name: ", SwingConstants.RIGHT));//指定右对齐标签
      northPanel.add(textField);
      northPanel.add(new JLabel("Password: ", SwingConstants.RIGHT));
      northPanel.add(passwordField);

      add(northPanel, BorderLayout.NORTH);//add方法

      JTextArea textArea = new JTextArea(TEXTAREA_ROWS, TEXTAREA_COLUMNS);
      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);
      insertButton.addActionListener(event ->
         textArea.append("User name: " + textField.getText() + " Password: "
            + new String(passwordField.getPassword()) + "\n"));

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

Text
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();//生成 TextComponentFrame类的GUI界面对象
         frame.setTitle("TextComponentTest");
         frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);//关闭界面的按钮操作
         frame.setVisible(true);//使结果可见的
      });
   }
}


 

 

测试程序3

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;

掌握复选框组件的用法;

记录示例代码阅读理解中存在的问题与疑惑。

 

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
{  //定义四个私有属性
   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.");//创建新标签
      label.setFont(new Font("Serif", Font.BOLD, FONTSIZE));//设置字体
      add(label, BorderLayout.CENTER);

      // this listener sets the font attribute of
      // the label to the check box state

      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));//设置面板中的字体
      };

      // add the check boxes

      JPanel buttonPanel = new JPanel();

      bold = new JCheckBox("Bold");//在构造器中指定标签文本
      bold.addActionListener(listener);
      bold.setSelected(true);//返回每个复选框的当前状态
      buttonPanel.add(bold);

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

      add(buttonPanel, BorderLayout.SOUTH);
      pack();//调整此窗口的大小
   }
}


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");//设置Title为复选框
         frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
         frame.setVisible(true);
      });
   }
}


 

 

测试程序4(本组程序)

elipse IDE中调试运行教材491页程序12-4,运行结果理解程序;

掌握单选按钮组件的用法;

记录示例代码阅读理解中存在的问题与疑惑。

package radioButton;

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

 

public class RadioButtonFrame extends JFrame
{
private JPanel buttonPanel;
private ButtonGroup group;
//使用相同的 ButtonGroup 对象创建一组按钮意味着“开启”其中一个按钮时,将关闭组中的其他所有按钮。
private JLabel label;
//可以通过设置垂直和水平对齐方式,指定标签显示区中标签内容在何处对齐
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.");//参数:由标签显示的文本。
label.setFont(new Font("Serif", Font.PLAIN, DEFAULT_SIZE));//设置此组件的字体
add(label, BorderLayout.CENTER);//设置组件位置


// 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);


// 此侦听器设置标签字体大小


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


button.addActionListener(listener);
}
}




 

测试程序5

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;

掌握边框的用法;

记录示例代码阅读理解中存在的问题与疑惑。

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();

      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);
   }
}



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);
      });
   }
}

 

 

 

测试程序6

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;

掌握组合框组件的用法;

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;

/**
 * A frame with a sample text label and a combo box for selecting font faces.
 */
public class ComboBoxFrame extends JFrame
{
   private JComboBox<String> faceCombo;//定义组合框面
   private JLabel label;//定义标签
   private static final int DEFAULT_SIZE = 24;

   public ComboBoxFrame()
   {
      // 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));//设置组件的字体
      add(label, BorderLayout.CENTER);

      // make a combo box and add face names
      //调用addItem方法添加选项
      faceCombo = new JComboBox<>();
      faceCombo.addItem("Serif");
      faceCombo.addItem("SansSerif");
      faceCombo.addItem("Monospaced");
      faceCombo.addItem("Dialog");
      faceCombo.addItem("DialogInput");

      // the combo box listener changes the label font to the selected face name

      faceCombo.addActionListener(event ->//组合框产生一个动作事件
         label.setFont(
            new Font(faceCombo.getItemAt(faceCombo.getSelectedIndex()), 
               Font.PLAIN, DEFAULT_SIZE)));

      // add combo box to a panel at the frame's southern border

      JPanel comboPanel = new JPanel();
      comboPanel.add(faceCombo);
      add(comboPanel, BorderLayout.SOUTH);
      pack();
   }
}


 

 

 

测试程序7

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;

掌握滑动条组件的用法;

记录示例代码阅读理解中存在的问题与疑惑。

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
      //添加一个普通滑块

      JSlider slider = new JSlider();//构造一个滑动条
      addSlider(slider, "Plain");

      // add a slider with major and minor ticks
      
       //添加一个有大和小刻度的滑块
      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);//设置标尺标记
      slider.setSnapToTicks(true);
      slider.setMajorTickSpacing(20);//每20个单位的位置显示一个大标尺标记
      slider.setMinorTickSpacing(5);//每5个单位的位置显示一个小标尺标记
      addSlider(slider, "Snap to ticks");

      // add a slider with no track
      //添加一个没有轨道的滑块
      slider = new JSlider();
      slider.setPaintTicks(true);
      slider.setMajorTickSpacing(20);
      slider.setMinorTickSpacing(5);
      slider.setPaintTrack(false);
      addSlider(slider, "No track");//添加滑块“无磁块”

      // add an inverted slider
      //添加一个倒滑块
      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
      //添加带有数字标签的滑块

      slider = new JSlider();
      slider.setPaintTicks(true);
      slider.setPaintLabels(true);//滑块设置面板标签
      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);//设置组件
      GridBagConstraints gbc = new GridBagConstraints();
      gbc.gridy = sliderPanel.getComponentCount();
      gbc.anchor = GridBagConstraints.WEST;
      sliderPanel.add(panel, gbc);
   }
}


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();//生成 SliderFrame类的GUI界面对象
         frame.setTitle("SliderTest");
         frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);////关闭界面的按钮操作
         frame.setVisible(true);//使结果可见
      });
   }


 

 

测试程序8

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;

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。

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

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;

掌握工具栏和工具提示的用法;

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);
      }
   }
}
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();//生成新的ToolBarFrame类的GUI界面
         frame.setTitle("ToolBarTest");
         frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);//关闭窗口界面
         frame.setVisible(true);//使结果可见
      });
   }

 

测试程序10

elipse IDE中调试运行教材524页程序12-1012-11,结合运行结果理解程序,了解GridbagLayout的用法。

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。

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;
   }
}
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);
         });
   }
}

 

 

 

测试程序11

elipse IDE中调试运行教材539页程序12-1312-14,结合运行结果理解程序;

掌握定制布局管理器的用法。

记录示例代码阅读理解中存在的问题与疑惑。

package circleLayout;

import java.awt.*;

/**
 * A layout manager that lays out components along a circle.
 */
public class CircleLayout implements LayoutManager
{//将布局管理器设置为空
   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)//将组件添加到布局中
   {
   }

   public void removeLayoutComponent(Component comp)//从布局中删去一个组件
   {
   }

   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;//计算最大组件宽度和高度
         }
      }
      minWidth = preferredWidth / 2;
      minHeight = preferredHeight / 2;
      sizesSet = true;
   }

   public Dimension preferredLayoutSize(Container parent)//返回布局下的容器的首选尺寸
   {
      setSizes(parent);
      Insets insets = parent.getInsets();
      int width = preferredWidth + insets.left + insets.right;
      int height = preferredHeight + insets.top + insets.bottom;//设置长、宽大小
      return new Dimension(width, height);
   }

   public Dimension minimumLayoutSize(Container parent)//返回布局下容器的最小尺寸
   {
      setSizes(parent);
      Insets insets = parent.getInsets();
      int width = minWidth + insets.left + insets.right;
      int height = minHeight + insets.top + insets.bottom;//设置最小尺寸
      return new Dimension(width, height);
   }

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

      // compute center of the circle
      //计算圆的中心
      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
       //计算圆的半径
      int xradius = (containerWidth - maxComponentWidth) / 2;
      int yradius = (containerHeight - maxComponentHeight) / 2;
      int radius = Math.min(xradius, yradius);//

      // lay out components along the circle
      //在圆周上布置组件

      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);
         }
      }
   }
}
package circleLayout;

import javax.swing.*;

/**
 * A frame that shows buttons arranged along a circle.
 */
public class CircleLayoutFrame extends JFrame
{
   public CircleLayoutFrame()
   {//调用add方法来添加各种按钮
      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();//调节大小
   }
}

1
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)
   {  //设置边框属性
      setBorder(BorderFactory.createTitledBorder(BorderFactory.createEtchedBorder(), title));
      setLayout(new BoxLayout(this, BoxLayout.Y_AXIS));
      group = new ButtonGroup();

      // make one radio button for each option
      //为每个选项设置一个单选按钮
      for (String option : options)
      {
         JRadioButton b = new JRadioButton(option);
         b.setActionCommand(option);
         add(b);
         group.add(b);
         b.setSelected(option == options[0]);
      }
   }

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


package 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");//设置标题为CircleLayoutTest
         frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);//关闭界面操作
         frame.setVisible(true);
      });
   }
}

 

测试程序12

elipse IDE中调试运行教材544页程序12-1512-16,结合运行结果理解程序;

掌握选项对话框的用法。

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

elipse IDE中调试运行教材552页程序12-1712-18,结合运行结果理解程序;

掌握对话框的创建方法;

记录示例代码阅读理解中存在的问题与疑惑。

package optionDialog;

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
{//定义长和宽的大小
   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");//建立新的对话框现象
      aboutItem.addActionListener(event -> {//并让他可见
         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.
      //按Exit退出程序

      JMenuItem exitItem = new JMenuItem("Exit");
      exitItem.addActionListener(event -> System.exit(0));
      fileMenu.add(exitItem);
   }
}
package dialog;

import java.awt.BorderLayout;

import javax.swing.JButton;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;

/**
 * A sample modal dialog that displays a message and waits for the user to click the OK button.
 */
public class AboutDialog extends JDialog
{
   public AboutDialog(JFrame owner)
   {
      super(owner, "About DialogTest", true);

      // add HTML label to center

      add(
            new JLabel(
                  "<html><h1><i>Core Java</i></h1><hr>By Cay Horstmann</html>"),
            BorderLayout.CENTER);//将HTML标签添加到中心

      // OK button closes the dialog
      //OK按钮关闭对话框
      JButton ok = new JButton("OK");
      ok.addActionListener(event -> setVisible(false));//监听器对象

      // add OK button to southern border

      JPanel panel = new JPanel();//创建新面板
      panel.add(ok);
      add(panel, BorderLayout.SOUTH);

      pack();
   }
}
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);
      });
   }

 

测试程序14

elipse IDE中调试运行教材556页程序12-1912-20,结合运行结果理解程序;

掌握对话框的数据交换用法;

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())) + "\n");
         }
      }
   }
}
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15

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;

掌握文件对话框的用法;

记录示例代码阅读理解中存在的问题与疑惑。

package fileChooser;

import java.awt.*;
import java.io.*;

import javax.swing.*;

/**
 * A file chooser accessory that previews images.
 */
public class ImagePreviewer extends JLabel
{
   /**
    * Constructs an ImagePreviewer.
    * @param chooser the file chooser whose property changes trigger an image
    *        change in this previewer
    */
   public ImagePreviewer(JFileChooser chooser)
   {
      setPreferredSize(new Dimension(100, 100));//设置此组件的首选大小
      setBorder(BorderFactory.createEtchedBorder());//设置此组件的边框

      chooser.addPropertyChangeListener(event -> {
         if (event.getPropertyName() == JFileChooser.SELECTED_FILE_CHANGED_PROPERTY)
         {
            // the user has selected a new file
            File f = (File) event.getNewValue();//创建一个新的文件对话框
            if (f == null)
            {
               setIcon(null);
               return;
            }

            // read the image into an icon
            //将图像读成图标
            ImageIcon icon = new ImageIcon(f.getPath());

            // if the icon is too large to fit, scale it
            //如果图标太大而无法容纳,将其缩放
            if (icon.getIconWidth() > getWidth())
               icon = new ImageIcon(icon.getImage().getScaledInstance(
                     getWidth(), -1, Image.SCALE_DEFAULT));

            setIcon(icon);//图标
         }
      });
   }
}
package fileChooser;

import java.io.*;

import javax.swing.*;
import javax.swing.filechooser.*;
import javax.swing.filechooser.FileFilter;

/**
 * A frame that has a menu for loading an image and a display area for the
 * loaded image.
 */
public class ImageViewerFrame extends JFrame
{
   private static final int DEFAULT_WIDTH = 300;
   private static final int DEFAULT_HEIGHT = 400;
   private JLabel label;
   private JFileChooser chooser;

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

      // set up menu bar
      JMenuBar menuBar = new JMenuBar();
      setJMenuBar(menuBar);

      JMenu menu = new JMenu("File");
      menuBar.add(menu);

      JMenuItem openItem = new JMenuItem("Open");
      menu.add(openItem);
      openItem.addActionListener(event -> {
         chooser.setCurrentDirectory(new File("."));

         // show file chooser dialog
            int result = chooser.showOpenDialog(ImageViewerFrame.this);

            // if image file accepted, set it as icon of the label
            if (result == JFileChooser.APPROVE_OPTION)
            {
               String name = chooser.getSelectedFile().getPath();
               label.setIcon(new ImageIcon(name));
               pack();
            }
         });

      JMenuItem exitItem = new JMenuItem("Exit");
      menu.add(exitItem);
      exitItem.addActionListener(event -> System.exit(0));

      // use a label to display the images
      //使用一个标签来显示图像标签
      label = new JLabel();
      add(label);

      // set up file chooser
      //设置文件选择器
      chooser = new JFileChooser();

      // accept all image files ending with .jpg, .jpeg, .gif
     
      FileFilter filter = new FileNameExtensionFilter(
            "Image files", "jpg", "jpeg", "gif");//接受各种形式
      chooser.setFileFilter(filter);

      chooser.setAccessory(new ImagePreviewer(chooser));
      //设置过滤器
      chooser.setFileView(new FileIconView(filter, new ImageIcon("palette.gif")));
   }
}
package fileChooser;

import java.io.*;
import javax.swing.*;
import javax.swing.filechooser.*;
import javax.swing.filechooser.FileFilter;

/**
 * A file view that displays an icon for all files that match a file filter.
 */
public class FileIconView extends FileView
{
   private FileFilter filter;
   private Icon icon;

   /**
    * Constructs a FileIconView.
    * @param aFilter a file filter--all files that this filter accepts will be shown 
    * with the icon.
    * @param anIcon--the icon shown with all accepted files.
    */
   public FileIconView(FileFilter aFilter, Icon anIcon)
   {
      filter = aFilter;
      icon = anIcon;
   }

   public Icon getIcon(File f)
   {
      if (!f.isDirectory() && filter.accept(f)) return icon;
      else return null;
   }
}
package fileChooser;

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

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

 

测试程序16

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;

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。

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。

总结:

这周由于实验内容过多,在老师的要求下我们选择了结对编程,首先通过测试了各个程序,大概了解了相关程序,然后通过结对编程,对我们组的测试程序进行了详细的注解。对需要我们负责的程序的相关内容进行了详细的了解,掌握了程序的基本构成和相关内容。但对于其他的内容还有很大的问题,需要解决。