201871010123-吴丽丽 《面向对象程序设计（Java）》第十四周学习总结

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()); //设置布局管理器为边框布局管理器 result = ;
lastCommand = "=";
start = true; // add the display display = new JButton(""); //创建一个按钮为“0”，将其赋给diaplay这个按钮
display.setEnabled(false); //将display这个按钮的控件设置为false，意味着这个控件不可用
add(display, BorderLayout.NORTH); //将display这个按钮添加到边框布局管理器的北位置
//创建两个动作
var insert = new InsertAction();
var command = new CommandAction(); // add the buttons in a 4 x 4 grid panel = new JPanel(); //创建一个新的JPanel对象
panel.setLayout(new GridLayout(, )); //创建一个四行四列的网格布局来设置这个面板的布局管理器
//以下是利用addButton方法来添加相应的按钮
addButton("", insert);
addButton("", insert);
addButton("", insert);
addButton("/", command); addButton("", insert);
addButton("", insert);
addButton("", insert);
addButton("*", command); addButton("", insert);
addButton("", insert);
addButton("", insert);
addButton("-", command); addButton("", insert);
addButton(".", insert);
addButton("=", command);
addButton("+", command); add(panel, BorderLayout.CENTER); //将panel（面板）添加到BorderLayout（边框布局）的中间
} /**
* Adds a button to the center panel.
* @param label the button label
* @param listener the button listener
*/
private void addButton(String label, ActionListener listener)
{
var button = new JButton(label); //创建一个新的名为label按钮
button.addActionListener(listener); //为按钮添加监听器，监听器对象为listener
panel.add(button); //在面板中添加按钮
} /**
* This action inserts the button action string to the end of the display text.
*/
//此操作将按钮操作字符串插入到显示文本的末尾
private class InsertAction implements ActionListener
{
public void actionPerformed(ActionEvent event)
{
String input = event.getActionCommand(); //通过事件得到动作命令赋给input对象
if (start)
{
display.setText("");
start = false;
}
display.setText(display.getText() + input);
}
} /**
* This action executes the command that the button action string denotes.
*/
// 此操作执行按钮操作字符串所表示的命令。
private class CommandAction implements ActionListener
{
public void actionPerformed(ActionEvent event)
{
String command = event.getActionCommand(); if (start)
{
if (command.equals("-"))
{
display.setText(command);
start = false;
}
else lastCommand = command;
}
else
{
calculate(Double.parseDouble(display.getText())); //Double.parseDouble（）是把通过按钮中获得的文本（数字类型的字符串），转换成double类型
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);
}
}

package calculator; import java.awt.*;
import javax.swing.*; /**
* @version 1.35 2018-04-10
* @author Cay Horstmann
*/
public class Calculator
{
public static void main(String[] args)
{
EventQueue.invokeLater(() -> {
var frame = new CalculatorFrame();
frame.setTitle("Calculator");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
});
}
}

package calculator; import javax.swing.*; /**
* A frame with a calculator panel.
*/
public class CalculatorFrame extends JFrame
{
public CalculatorFrame()
{
add(new CalculatorPanel()); //构建一个新的计算器面板添加到计算器框架中
pack(); //pack()方法用来调整框架的大小，以适合其子组件的首选大小和布局
}
}

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 = ;
public static final int TEXTAREA_COLUMNS = ; public TextComponentFrame()
{
var textField = new JTextField(); //创建一个新的文本域，赋给textField对象
var passwordField = new JPasswordField(); //创建一个新的密码域，并赋给passwordField对象 var northPanel = new JPanel();
northPanel.setLayout(new GridLayout(, )); //创建一个两行两列的网络布局，将其设置为northPanel的布局管理器
northPanel.add(new JLabel("User name: ", SwingConstants.RIGHT)); //构建新的标签，将其添加到northPanel中
northPanel.add(textField); //将文本域添加到northPanel面板中
northPanel.add(new JLabel("Password: ", SwingConstants.RIGHT));
northPanel.add(passwordField); //将密码域添加到northPanel面板中 add(northPanel, BorderLayout.NORTH); //将northPanel添加到边框布局的北位置 var textArea = new JTextArea(TEXTAREA_ROWS, TEXTAREA_COLUMNS); //创建一个设置了行与列的文本区
var scrollPane = new JScrollPane(textArea); //创建一个滚动窗格，用来显示文本区，当组件内容超过显示范围时，滚动条会自动出现 add(scrollPane, BorderLayout.CENTER); //将滚动窗格添加中边框布局的中间位置 // add button to append text into the text area var southPanel = new JPanel(); var insertButton = new JButton("Insert");
southPanel.add(insertButton);
insertButton.addActionListener(event ->
textArea.append("User name: " + textField.getText() + " Password: "
+ new String(passwordField.getPassword()) + "\n")); //textArea.append这表示将给定的文本追加到文本区已有文本的尾部
add(southPanel, BorderLayout.SOUTH);
pack();
}
}

package text;import java.awt.*;
import javax.swing.*;/**
* @version 1.42 2018-04-10
* @author Cay Horstmann
*/
public class TextComponentTest
{
public static void main(String[] args)
{
EventQueue.invokeLater(() -> {
var frame = new TextComponentFrame();
frame.setTitle("TextComponentTest");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
});
}
}

package checkBox; import java.awt.*;
import javax.swing.*; /**
* @version 1.35 2018-04-10
* @author Cay Horstmann
*/
public class CheckBoxTest
{
public static void main(String[] args)
{
EventQueue.invokeLater(() -> {
var frame = new CheckBoxFrame();
frame.setTitle("CheckBoxTest");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
});
}
}

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; //复选框
private JCheckBox italic; //复选框
private static final int FONTSIZE = ; public CheckBoxFrame()
{
// add the sample text label label = new JLabel("The quick brown fox jumps over the lazy dog."); //创建一个新的标签，并赋给label对象
label.setFont(new Font("Serif", Font.BOLD, FONTSIZE)); //为label设置字体
add(label, BorderLayout.CENTER); //将label添加到边框布局的中间位置 // this listener sets the font attribute of
// the label to the check box state
//actionPerformed方法查询bold和italic两个复选框的状态，并且设置面板中的字体
ActionListener listener = event -> { //为复选框设置一个动作监听器，两个复选框选用了同一个动作监听器
int mode = ;
if (bold.isSelected()) mode += Font.BOLD; //isSelected方法将返回每个复选框的当前状态
if (italic.isSelected()) mode += Font.ITALIC;
label.setFont(new Font("Serif", mode, FONTSIZE));
}; // add the check boxes
//以下是将两个复选框添加到buttonPanel的操作
var 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();
}
}

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 = ; 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(); //为单选钮组构造一个ButtonGroup的对象
//用addRadioButton方法来传递按钮
addRadioButton("Small", );
addRadioButton("Medium", );
addRadioButton("Large", );
addRadioButton("Extra large", ); 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;
var button = new JRadioButton(name, selected); //为按钮构造一个JRadioButton的对象
group.add(button); //将按钮添加到按钮组中
buttonPanel.add(button); //将按钮添加按钮面板中 // this listener sets the label font size ActionListener listener = event -> label.setFont(new Font("Serif", Font.PLAIN, size)); //定义了一个动作监听器用来把字体设置为特定值 button.addActionListener(listener); //每个单选钮都对应一个不同的监听器对象
}
}

package radioButton;import java.awt.*;
import javax.swing.*;/**
* @version 1.35 2018-04-10
* @author Cay Horstmann
*/
public class RadioButtonTest
{
public static void main(String[] args)
{
EventQueue.invokeLater(() -> {
var frame = new RadioButtonFrame();
frame.setTitle("RadioButtonTest");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
});
}
}

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(); //为单选钮组构造一个ButtonGroup的对象 addRadioButton("Lowered bevel", BorderFactory.createLoweredBevelBorder()); //传递一个具有凹面效果的边框的参数
addRadioButton("Raised bevel", BorderFactory.createRaisedBevelBorder()); //传递一个具有凸面效果的边框参数
addRadioButton("Etched", BorderFactory.createEtchedBorder()); //传递一个具有3D效果的直线边框参数
addRadioButton("Line", BorderFactory.createLineBorder(Color.BLUE)); //传递一个简单的直线边框参数
addRadioButton("Matte", BorderFactory.createMatteBorder(, , , , Color.BLUE)); //传递一个用color颜色填充的粗边框参数
addRadioButton("Empty", BorderFactory.createEmptyBorder()); //传递一个空边框参数
//将一个带有标题的浊刻边框添加到一个按钮面板上
Border etched = BorderFactory.createEtchedBorder();
Border titled = BorderFactory.createTitledBorder(etched, "Border types");
buttonPanel.setBorder(titled); setLayout(new GridLayout(, )); //构建一个两行一列的网络布局来设置布局管理器
add(buttonPanel);
add(demoPanel);
pack();
} public void addRadioButton(String buttonName, Border b)
{
var button = new JRadioButton(buttonName);
button.addActionListener(event -> demoPanel.setBorder(b)); //向按钮添加了动作监听器，动作监听器用来设置组件b的边框
group.add(button);
buttonPanel.add(button);
}
}

package border; import java.awt.*;
import javax.swing.*; /**
* @version 1.35 2018-04-10
* @author Cay Horstmann
*/
public class BorderTest
{
public static void main(String[] args)
{
EventQueue.invokeLater(() -> {
var frame = new BorderFrame();
frame.setTitle("BorderTest");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
});
}
}

package comboBox;import java.awt.BorderLayout;
import java.awt.Font;import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;/**
* A frame with a sample text label and a combo box for selecting font faces.
*/
public class ComboBoxFrame extends JFrame
{
private JComboBox<String> faceCombo; //泛型类组合框
private JLabel label;
private static final int DEFAULT_SIZE = ; 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"); //调用addItem方法来增加选项
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()), //通过getSelectedIndex方法获取选择的选项，再通过getItemAt方法获取选项的位置，从而设置字体
Font.PLAIN, DEFAULT_SIZE))); // add combo box to a panel at the frame's southern border
//将组合项添加组合面板上，再将组合面板添加到边框的南位置
var comboPanel = new JPanel();
comboPanel.add(faceCombo);
add(comboPanel, BorderLayout.SOUTH);
pack();
}
}

package comboBox; import java.awt.*;
import javax.swing.*; /**
* @version 1.36 2018-04-10
* @author Cay Horstmann
*/
public class ComboBoxTest
{
public static void main(String[] args)
{
EventQueue.invokeLater(() -> {
var frame = new ComboBoxFrame();
frame.setTitle("ComboBoxTest");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
});
}
}