第十四周作业
本人学号：201771010138
姓名：邹丰蔚
《面向对象程序设计（java）》第十四周学习总结
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；
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Calculator： 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); }); } }
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CalculatorFrame: package calculator;
import javax.swing.*;
/** * A frame with a calculator panel. */ public class CalculatorFrame extends JFrame { public CalculatorFrame() { add(new CalculatorPanel()); pack(); } }
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CalculatorPanel: 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 { 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.setEnabled(false); add(display, BorderLayout.NORTH);
ActionListener insert = new InsertAction(); ActionListener command = new CommandAction();
// add the buttons in a 4 x 4 grid
panel = new JPanel(); panel.setLayout(new GridLayout(4, 4));
addButton("7", insert); addButton("8", insert); addButton("9", insert); addButton("/", command);
addButton("4", insert); addButton("5", insert); addButton("6", insert); addButton("*", command);
addButton("1", insert); addButton("2", insert); addButton("3", insert); addButton("-", command);
addButton("0", insert); addButton(".", insert); addButton("=", command); addButton("+", command);
add(panel, BorderLayout.CENTER); }
/** * 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(); if (start) { display.setText(""); 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())); lastCommand = command; 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); } } |
得出结果：
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。
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TextComponentTest: 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); }); } } |
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TextComponentFrame: 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 { 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)); 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);
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(); } } |
得出结果：
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。
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CheckBoxTest: 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); }); } }
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CheckBoxFrame: 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() { // add the sample text label
label = new JLabel("The quick brown fox jumps over the lazy dog."); label.setFont(new Font("Serif", Font.BOLD, FONTSIZE)); 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)); };
// add the check boxes
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(); } } |
得出结果：
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。
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RadioButtonTest: 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); }); } } |
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RadioButtonFrame: package radioButton;
import java.awt.*; import java.awt.event.*; import javax.swing.*;
/** * A frame with a sample text label and radio buttons for selecting font sizes. */ public class RadioButtonFrame extends JFrame { private JPanel buttonPanel; private ButtonGroup group; private JLabel label; private static final int DEFAULT_SIZE = 36;
public RadioButtonFrame() { // 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(); }
/** * 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);
// this listener sets the label font size
ActionListener listener = event -> label.setFont(new Font("Serif", Font.PLAIN, size));
button.addActionListener(listener); } } |
得出结果：
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。
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BorderTest： 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); }); } }
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BorderFrame： 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); } }
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得出结果：
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。
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ComboBoxTest: 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) { EventQueue.invokeLater(() -> { JFrame frame = new ComboBoxFrame(); frame.setTitle("ComboBoxTest"); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); frame.setVisible(true); }); } } |
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ComboBoxFrame： 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; private JLabel label; 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)); add(label, BorderLayout.CENTER);
// make a combo box and add face names
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 -> 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(); } } |
得出结果：
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。
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SliderTest： 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); }); } } |
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SliderFrame： 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); } } |
得出结果：
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。
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MenuTest： 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); }); } } |
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MenuFrame： 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); } }
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得出结果：
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；
记录示例代码阅读理解中存在的问题与疑惑。
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ToolBarText： 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); }); } } |
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ToolBarFrame： 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); } } } |
得出结果：
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。
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GridLayoutTest： 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); }); } } |
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GBC： 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; } }
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FontFrame： 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<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(); } } |
得出结果：
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GroupLayoutTest： 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); }); } } |
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FontFrame： 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<String> face; private JComboBox<Integer> 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(); }
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(); } }
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得出结果：
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。
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CircleLayoutTest： 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); }); } } |
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CircleLayoutFrame： 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(); } } |
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CircleLayout： 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); } } } } |
得出结果:
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。
记录示例代码阅读理解中存在的问题与疑惑。
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OptionDialogTest： 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); }); } }
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OptionDialogFrame： 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); } }
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ButtonPanel： 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(); } }
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得出结果:
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。
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DialogTest: 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); }); } } |
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DialogFrame: 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); } }
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AboutDialog: 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(); } } |
得出结果：
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。
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DataExchangeTest： 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); }); } } |
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DataExchangeFrame： 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"); } } } } |
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PasswordChooser： 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; } } |
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User： 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; } } |
得出结果：
测试程序15
l 在elipse IDE中调试运行教材556页程序12-21、12-2212-23，结合程序运行结果理解程序；
l 掌握文件对话框的用法;
记录示例代码阅读理解中存在的问题与疑惑。
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FileChooserTest： 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); }); } } |
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FileIconView： 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; } } |
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ImagePreviwer： package fileChooser;
import java.awt.*; import java.io.*;
import javax.swing.*;
/** * A file chooser accessory that previews images. */ public class ImagePreviewer extends JLabel { /** * Constructs an ImagePreviewer. * @param chooser the file chooser whose property changes trigger an image * change in this previewer */ public ImagePreviewer(JFileChooser chooser) { setPreferredSize(new Dimension(100, 100)); setBorder(BorderFactory.createEtchedBorder());
chooser.addPropertyChangeListener(event -> { if (event.getPropertyName() == JFileChooser.SELECTED_FILE_CHANGED_PROPERTY) { // the user has selected a new file File f = (File) event.getNewValue(); if (f == null) { setIcon(null); return; }
// read the image into an icon ImageIcon icon = new ImageIcon(f.getPath());
// if the icon is too large to fit, scale it if (icon.getIconWidth() > getWidth()) icon = new ImageIcon(icon.getImage().getScaledInstance( getWidth(), -1, Image.SCALE_DEFAULT));
setIcon(icon); } }); } }
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ImageViewerFrame: 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 label = new JLabel(); add(label);
// set up file chooser chooser = new JFileChooser();
// accept all image files ending with .jpg, .jpeg, .gif FileFilter filter = new FileNameExtensionFilter( "Image files", "jpg", "jpeg", "gif"); chooser.setFileFilter(filter);
chooser.setAccessory(new ImagePreviewer(chooser));
chooser.setFileView(new FileIconView(filter, new ImageIcon("palette.gif"))); } } |
得出结果：
测试程序16
l 在elipse IDE中调试运行教材570页程序12-24，结合运行结果理解程序；
l 了解颜色选择器的用法。
l 记录示例代码阅读理解中存在的问题与疑惑。
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ColorChooserTest： package colorChooser;
import java.awt.*; import javax.swing.*;
/** * @version 1.04 2015-06-12 * @author Cay Horstmann */ public class ColorChooserTest { public static void main(String[] args) { EventQueue.invokeLater(() -> { JFrame frame = new ColorChooserFrame(); frame.setTitle("ColorChooserTest"); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); frame.setVisible(true); }); } } |
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ColorChooserPanel： package colorChooser;
import java.awt.Color; import java.awt.Frame; import java.awt.event.ActionEvent; import java.awt.event.ActionListener;
import javax.swing.JButton; import javax.swing.JColorChooser; import javax.swing.JDialog; import javax.swing.JPanel;
/** * A panel with buttons to pop up three types of color choosers */ public class ColorChooserPanel extends JPanel { public ColorChooserPanel() { JButton modalButton = new JButton("Modal"); modalButton.addActionListener(new ModalListener()); add(modalButton);
JButton modelessButton = new JButton("Modeless"); modelessButton.addActionListener(new ModelessListener()); add(modelessButton);
JButton immediateButton = new JButton("Immediate"); immediateButton.addActionListener(new ImmediateListener()); add(immediateButton); }
/** * This listener pops up a modal color chooser */ private class ModalListener implements ActionListener { public void actionPerformed(ActionEvent event) { Color defaultColor = getBackground(); Color selected = JColorChooser.showDialog(ColorChooserPanel.this, "Set background", defaultColor); if (selected != null) setBackground(selected); } }
/** * This listener pops up a modeless color chooser. The panel color is changed when the user * clicks the OK button. */ private class ModelessListener implements ActionListener { private JDialog dialog; private JColorChooser chooser;
public ModelessListener() { chooser = new JColorChooser(); dialog = JColorChooser.createDialog(ColorChooserPanel.this, "Background Color", false /* not modal */, chooser, event -> setBackground(chooser.getColor()), null /* no Cancel button listener */); }
public void actionPerformed(ActionEvent event) { chooser.setColor(getBackground()); dialog.setVisible(true); } }
/** * This listener pops up a modeless color chooser. The panel color is changed immediately when * the user picks a new color. */ private class ImmediateListener implements ActionListener { private JDialog dialog; private JColorChooser chooser;
public ImmediateListener() { chooser = new JColorChooser(); chooser.getSelectionModel().addChangeListener( event -> setBackground(chooser.getColor()));
dialog = new JDialog((Frame) null, false /* not modal */); dialog.add(chooser); dialog.pack(); }
public void actionPerformed(ActionEvent event) { chooser.setColor(getBackground()); dialog.setVisible(true); } } } |
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ColorChooserFrame： package colorChooser;
import javax.swing.*;
/** * A frame with a color chooser panel */ public class ColorChooserFrame extends JFrame { private static final int DEFAULT_WIDTH = 300; private static final int DEFAULT_HEIGHT = 200;
public ColorChooserFrame() { setSize(DEFAULT_WIDTH, DEFAULT_HEIGHT);
// add color chooser panel to frame
ColorChooserPanel panel = new ColorChooserPanel(); add(panel); } } |
得出结果：
实验2：组内讨论反思本组负责程序，理解程序总体结构，梳理程序GUI设计中应用的相关组件，整理相关组件的API,对程序中组件应用的相关代码添加注释。
所添加注释：
package 课本示例13;
import java.awt.*; import javax.swing.*;
/** * @version 1.34 2015-06-12 * @author Cay Horstmann */ public class OptionDialogTest { public static void main(String[] args) { EventQueue.invokeLater(() -> { JFrame frame = new OptionDialogFrame(); frame.setTitle("OptionDialogTest"); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); frame.setVisible(true); }); } }
package 课本示例13;
import java.awt.*; import java.awt.event.*; import java.awt.geom.*; import java.util.*; import javax.swing.*;
/** * 包含用于选择各种选项对话框的设置的框架。 */ public class OptionDialogFrame extends JFrame { private ButtonPanel typePanel; private ButtonPanel messagePanel; private ButtonPanel messageTypePanel; private ButtonPanel optionTypePanel; private ButtonPanel optionsPanel; private ButtonPanel inputPanel; private String messageString = "Message"; private Icon messageIcon = new ImageIcon("blue-ball.gif"); private Object messageObject = new Date(); private Component messageComponent = new SampleComponent();
public OptionDialogFrame() { JPanel gridPanel = new JPanel(); gridPanel.setLayout(new GridLayout(2, 3));
typePanel = new ButtonPanel("Type", "Message", "Confirm", "Option", "Input"); messageTypePanel = new ButtonPanel("Message Type", "ERROR_MESSAGE", "INFORMATION_MESSAGE", "WARNING_MESSAGE", "QUESTION_MESSAGE", "PLAIN_MESSAGE"); messagePanel = new ButtonPanel("Message", "String", "Icon", "Component", "Other", "Object[]"); optionTypePanel = new ButtonPanel("Confirm", "DEFAULT_OPTION", "YES_NO_OPTION", "YES_NO_CANCEL_OPTION", "OK_CANCEL_OPTION"); optionsPanel = new ButtonPanel("Option", "String[]", "Icon[]", "Object[]"); inputPanel = new ButtonPanel("Input", "Text field", "Combo box");
gridPanel.add(typePanel); gridPanel.add(messageTypePanel); gridPanel.add(messagePanel); gridPanel.add(optionTypePanel); gridPanel.add(optionsPanel); gridPanel.add(inputPanel);
// add a panel with a Show button
JPanel showPanel = new JPanel(); JButton showButton = new JButton("Show"); showButton.addActionListener(new ShowAction()); showPanel.add(showButton);
add(gridPanel, BorderLayout.CENTER); add(showPanel, BorderLayout.SOUTH); pack(); }
/** * Gets the currently selected message. * @return a string, icon, component, or object array, depending on the Message panel selection */ public Object getMessage() { String s = messagePanel.getSelection(); if (s.equals("String")) return messageString; else if (s.equals("Icon")) return messageIcon; else if (s.equals("Component")) return messageComponent; else if (s.equals("Object[]")) return new Object[] { messageString, messageIcon, messageComponent, messageObject }; else if (s.equals("Other")) return messageObject; else return null; }
/** * Gets the currently selected options. * @return an array of strings, icons, or objects, depending on the Option panel selection */ public Object[] getOptions() { String s = optionsPanel.getSelection(); if (s.equals("String[]")) return new String[] { "Yellow", "Blue", "Red" }; else if (s.equals("Icon[]")) return new Icon[] { new ImageIcon("yellow-ball.gif"), new ImageIcon("blue-ball.gif"), new ImageIcon("red-ball.gif") }; else if (s.equals("Object[]")) return new Object[] { messageString, messageIcon, messageComponent, messageObject }; else return null; }
/** * 获取所选消息或选项类型 * @param面板消息类型或确认面板 * @return JOptionPane类中选定的XXX_MESSAGE或XXX_OPTION常量 */ public int getType(ButtonPanel panel) { String s = panel.getSelection(); try { return JOptionPane.class.getField(s).getInt(null); } catch (Exception e) { return -1; } }
/** * “显示”按钮的动作侦听器显示“确认”，“输入”，“消息”或“选项”对话框 *取决于“类型”面板选择。 */ private class ShowAction implements ActionListener { public void actionPerformed(ActionEvent event) { if (typePanel.getSelection().equals("Confirm")) JOptionPane.showConfirmDialog( OptionDialogFrame.this, getMessage(), "Title", getType(optionTypePanel), getType(messageTypePanel)); else if (typePanel.getSelection().equals("Input")) { if (inputPanel.getSelection().equals("Text field")) JOptionPane.showInputDialog( OptionDialogFrame.this, getMessage(), "Title", getType(messageTypePanel)); else JOptionPane.showInputDialog(OptionDialogFrame.this, getMessage(), "Title", getType(messageTypePanel), null, new String[] { "Yellow", "Blue", "Red" }, "Blue"); } else if (typePanel.getSelection().equals("Message")) JOptionPane.showMessageDialog( OptionDialogFrame.this, getMessage(), "Title", getType(messageTypePanel)); else if (typePanel.getSelection().equals("Option")) JOptionPane.showOptionDialog( OptionDialogFrame.this, getMessage(), "Title", getType(optionTypePanel), getType(messageTypePanel), null, getOptions(), getOptions()[0]); } } }
/** * 具有涂漆表面的组件 */
class SampleComponent extends JComponent { public void paintComponent(Graphics g) { Graphics2D g2 = (Graphics2D) g; Rectangle2D rect = new Rectangle2D.Double(0, 0, getWidth() - 1, getHeight() - 1); g2.setPaint(Color.YELLOW); g2.fill(rect); g2.setPaint(Color.BLUE); g2.draw(rect); }
public Dimension getPreferredSize() { return new Dimension(10, 10); } }
package 课本示例13;
import javax.swing.*;
/**
* 带标题边框内的单选按钮的面板.
*/
public class ButtonPanel extends JPanel
{
private ButtonGroup group;
/**
* 构造一个按钮面板.
* @param标题边框中显示的标题
* @param选项一组单选按钮标签
*/
public ButtonPanel(String title, String... options)
{
setBorder(BorderFactory.createTitledBorder(BorderFactory.createEtchedBorder(), title));
setLayout(new BoxLayout(this, BoxLayout.Y_AXIS));
group = new ButtonGroup();
// make one radio button for each option
for (String option : options)
{
JRadioButton b = new JRadioButton(option);
b.setActionCommand(option);
add(b);
group.add(b);
b.setSelected(option == options[0]);
}
}
/**
* 获取当前选定的选项。
* @return当前所选单选按钮的标签。
*/
public String getSelection()
{
return group.getSelection().getActionCommand();
}
}
GUI相关组件：
GUI窗口
Jframe是窗体组件。创建该组件即创建了一个窗口。窗口是一个容器组件，所有内容均可以放入其中。
创建窗体对象：
JFrame frame = newJFrame(“标题”);
// 在这里需要简单设置属性:
frame.setSize(int 宽,int 高); //设置窗体尺寸
frame.setLocation(int x轴，int y轴); //设置窗体位置
frame. setVisible(true); //设置窗体可见
this.setResizable(false); //设置窗体大小固定
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);// 关闭窗口默认操作
向窗体中添加其他组件：
frame.add(其他组件);
GUI布局
布局是指界面存放组件位置的方式。
如果组件凌乱地存放在容器当中不好看，通常可以采用对应布局方式，来规范组件的位置,Java也提供了常见的布局对象。
LayoutManager： 布局接口，各种布局类均为其子类
frame.setLayout(布局对象) //设置窗口布局
null：不使用布局，此时可以容器内的组件可以调用方法，通过坐标以及尺寸进行组件定位：
组件定位方法为void setBounds(int x轴，int y轴，int 宽度，int 高度)
BorderLayout：边界布局，将界面分为东西南北中5个方位，frame的默认布局
GUI面板
JPanel面板与JFrame窗体类似，属于容器组件，可以存放其他组件内容。通常用来划分区域，完成一个完整的功能。
通常的方式是： JFrame存放JPanel，JPanel存放其他组件。
GUI按钮
在容器内最终完成数据展示与交互的均为功能组件。组件众多，其他组件的使用方法均类似，这里不一一介绍。欢迎界面中使用到了Button组件。
Button btn = new Button();
通用步骤：
1、创建功能组件对象;
2、给功能组件绑定监听器;
3、将功能组件添加到容器组件中;
GUI监听器
页面中的各种组件均包含一些Java预设的用户操作(如鼠标点击，键盘按键等)，如何在用户完成对应操作时，执行对应的代码，是事件监听机制完成的。
将发生预设事件的组件绑定监听器，监听器某个组件是否发生了用户操作，当用户进行对应的操作后，执行对应代码。
我们最常见的操作是鼠标点击按钮，是按钮的动作。这里介绍按钮的事件监听。
事件监听步骤：
① 被监听的组件调用方法与监听器关联
按钮组件关联监听器方法：addActionListener(监听器对象)
按钮动作监听器接口：ActionListener
② 在监听器中定义用户操作对应的执行代码
实验3：组间协同学习：在本班课程QQ群内，各位同学对实验1中存在的问题进行提问，提问时注明实验1中的测试程序编号，负责对应程序的小组需及时对群内提问进行回答。
总结：
本周学习内容较多，所以我们采用了自小组协作学习模式。通过小组内的商讨大致理解了这些测试程序的基本思路；也在合作伙伴的身上学到了一些学习的方法。通过本周的小组学习，我们收获了自主学习所得不到的好处，那就是学习理解别人的学习感悟和知识理解。希望在这周学习完之后，可以对此问题有了更深入的了解。
