201871010106-丁宣元 《面向对象程序设计(java)》第十五周学习总结

                   201871010106-丁宣元 《面向对象程序设计(java)》第十五周学习总结

正文开头:

项目

内容

这个作业属于哪个课程

https://home.cnblogs.com/u/nwnu-daizh/

这个作业的要求在哪里

https://www.cnblogs.com/nwnu-daizh/p/11995615.html 

作业学习目标

(1) 掌握菜单组件用途及常用API;

(2) 掌握对话框组件用途及常用API;

(3) 学习设计简单应用程序的GUI。

正文内容:

第一部分:总结第十二章理论知识

                            第十二章(续)

  12-4菜单(是GUI常用的一个组件)

    1.创建菜单栏:可以添加到容器组件的任何位置,通常在框架的顶部           

        eg:JMenuBar menuBar = new JMenuBar()      

    2.添加到框架:            

         frame.setJMenuBar(menuBar);      

    3.创建菜单对象,并将对象添加到菜单栏中

         JMenu editMenu=new JMenu("Edit");
         menuBar.add(editMenu);
    4.向菜单对象添加菜单项
         JMenuItem pasteItem=new JMenuItem();

         editMenu.add(pasteItem);

    5.添加分隔符
         editMenu.addSeparator();

    6.向对象添加子菜单:
         JMenu optionsMenu=new Jmenu("option");
         editMenu.add(optionsMenu);

    7.监听器

      用户选择菜单时,触发一个动作,需要安装一个动作监听器

         ActionListener listener=...;

         pasteItem.addActionListener(listener);

      菜单对象的add方法可返回创建的子菜单项。可以用下列方法获得她,并添加监听器:

         JMenuItem pasteItem =editMenu.add("Paste");

         pasteItem.addActionListener(listener);

    8.弹出菜单JpopMenu

       创建弹出菜单:JpopMenu popup=new JpopMenu();弹出菜单没有标题

       添加菜单项:JMenuItem item = new JMenuItem("Cut");

             item.addActionListener(listener);

             popup.add(item);

       弹出菜单用show才能显示:popup.show(panel,x,y);

       弹出式触发器:用户点击鼠标的某个键时弹出菜单

          调用方法设置弹出式触发器:component.setComponentPopMenu(popup);

    9.快捷键

        eg:JMenuItem CutItem = new JMenuItem("Index");

         CutItem.setMnemonic("|");快捷键下有一条下划线

    10.加速器

      使用setAccelerator方法可以将加速器关联到一个菜单项。

      eg:openItem.setAccelerator(KeyStroke.getKeyStrock("ctrl o"));

        菜单项并不打开菜单,而是直接激活菜单关联的动作事件
    11.启用或禁用菜单项

      a.屏蔽/启用菜单项的方法:

        aMenuItem.setEnabled(boolean);

          boolean为false时,屏蔽;为true时,启用

      b.动态启用/屏蔽某菜单项,需要为菜单项注册“menuSelectd"事件监听器

    12.工具栏JToolBar(可以移动,拖拽)

       优点:可以移动,脱离菜单栏或拖拽到框架其他地方

       工具提示:某个按钮的含义

             setToolTest方法添加工具提示到JComponent;

             exitButton.setToolTipText("Exit");

        另一种方法就是,如果使用Action对象,就可以用SHORT-DESCRIPTION关联工具提示
  12-5对话框

    1.对话框:大小不能变,不能有菜单的容器窗口

         不可以作为应用程序的主框架,必须包含在其他容器中

      多种形式的对话框:

        JOptionPane:支持简单,标准的对话框

        JFileChooser:支持文件打开,保存对话框

        ProgressMonitor:支持操作动作条控制对话框

      对话框依赖框架

      对话框分为无模式和有模式两种

          有模式:处于激活状态时,程序只能响应对话框内部的事件,不能再激活依赖的窗口或组件,且将堵塞当前线程的执行,即堵        塞使得对话框处于激活状态的线程,直到该对话框消失不可见;

          无模式:处于激活状态时,程序仍能激活它所依赖的窗口或者组件,不能堵塞线程的执行。

   2.选项对话框:

    (1)JOptionPane提供的对话框是模式对话框,可以创建和对定义问题、信息、警告、和错误等几种类型的对话框。

    (2)JOptionPane类:定义了多个showXxxDiaglog形式的静态方法

      showMessageDialog信息对话框

      showConfirmDiaglog确认对话框

      showOptionDialog选项对话框

      showInputDialog输入对话框

        showXxxDiaglo的方法参数:Component parentCopmonent

                    Object message

                    String title

                    int messageType

    (3)创建对话框:

          JDialog  (Frame owner) 没有标题的非模式对话框

          JDialog(Frame owner ,boolean modal) 没有标题的对话框

          JDialog(Frame owner ,String title)  有标题的非模式对话框

          JDialog(Frame owner ,String title,boolean modal)有标题的对话框。

    

 

第二部分:实验部分

 实验1: 导入第12示例程序,测试程序并进行组内讨论。

   测试程序1

    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。

  代码:

 

package menu;

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

/**
 * @version 1.25 2018-04-10
 * @author Cay Horstmann
 */
public class MenuTest
{
   public static void main(String[] args)
   {
      EventQueue.invokeLater(() -> {
         MenuFrame frame = new MenuFrame();
         frame.setTitle("MenuTest");
         frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
         frame.setVisible(true);
      });
   }
}

 

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//菜单项触发命令,通常采用扩展抽象类AbstractAction来定义一个实现Action接口的类
   {
      public TestAction(String name)
      {
         super(name);
      }

      public void actionPerformed(ActionEvent event)
      {
         System.out.println(getValue(Action.NAME) + " selected.");
      }
   }

   public MenuFrame()  //构造器
   {
      setSize(DEFAULT_WIDTH, DEFAULT_HEIGHT);

      JMenu fileMenu = new JMenu("File");//为菜单建立一个菜单对象
      fileMenu.add(new TestAction("New"));

      // demonstrate accelerators

      JMenuItem openItem = fileMenu.add(new TestAction("Open"));//添加菜单项open
      openItem.setAccelerator(KeyStroke.getKeyStroke("ctrl O"));//快捷键,与ctrl O联系

      fileMenu.addSeparator();//添加分隔符

      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);//真实功能
            }
         });

      // 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);//启用或禁用菜单选项利用setEnabled方法
               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有图标

      TestAction cutAction = new TestAction("Cut");
      cutAction.putValue(Action.SMALL_ICON, new ImageIcon("cut.gif"));
      TestAction copyAction = new TestAction("Copy");
      copyAction.putValue(Action.SMALL_ICON, new ImageIcon("copy.gif"));
      TestAction 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
      var 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();//创建菜单栏
      setJMenuBar(menuBar);//将菜单栏添加到框架上

      menuBar.add(fileMenu);//将顶层菜单添加到菜单栏中
      menuBar.add(editMenu);
      menuBar.add(helpMenu);

      // demonstrate pop-ups弹出菜单

      popup = new JPopupMenu();//创建弹出菜单
      popup.add(cutAction);
      popup.add(copyAction);
      popup.add(pasteAction);

      JPanel panel = new JPanel();
      panel.setComponentPopupMenu(popup);
      add(panel);
   }
}

  结果:

 

 

 

    疑惑:这个程序对我来说阅读难度较大,有许多代码不能理解。

  测试程序2

    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。

  代码

 

package toolBar;

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

/**
 * @version 1.15 2018-04-10
 * @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);
      });
   }
}

 

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);//边框布局的中

      // set up actions

      ColorAction blueAction = new ColorAction("Blue", new ImageIcon("blue-ball.gif"), Color.BLUE);
      ColorAction yellowAction = new ColorAction("Yellow", new ImageIcon("yellow-ball.gif"),
            Color.YELLOW);
      ColorAction redAction = new ColorAction("Red", new ImageIcon("red-ball.gif"), Color.RED);

      AbstractAction 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();//创建工具栏
      bar.add(blueAction);//将组件添加到工具栏中
      bar.add(yellowAction);
      bar.add(redAction);
      bar.addSeparator();
      bar.add(exitAction);
      add(bar, BorderLayout.NORTH);//置于边框布局的北

      // 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//菜单项触发命令
   {
      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)//重写actionPerformed方法
      {
         Color c = (Color) getValue("Color");
         panel.setBackground(c);
      }
   }
}

  结果:

  

 测试程序3

    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。

  代码:

 

package optionDialog;

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

/**
 * @version 1.35 2018-04-10
 * @author Cay Horstmann
 */
public class OptionDialogTest
{
   public static void main(String[] args)
   {
      EventQueue.invokeLater(() -> {
          OptionDialogFrame frame = new OptionDialogFrame();
         frame.setTitle("OptionDialogTest");
         frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
         frame.setVisible(true);
      });
   }
}

 

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));//设置边框效果
      setLayout(new BoxLayout(this, BoxLayout.Y_AXIS));
      group = new ButtonGroup();

      // make one radio button for each option
      for (String option : options)//for-each循环打印
      {
         JRadioButton button = new JRadioButton(option);
         button.setActionCommand(option);
         add(button);
         group.add(button);
         button.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 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//继承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()
   {
      var 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[]");//五个按钮
      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

      var showPanel = new JPanel();
      var showButton = new JButton("Show");
      showButton.addActionListener(new ShowAction());
      showPanel.add(showButton);

      add(gridPanel, BorderLayout.CENTER);//加于中间
      add(showPanel, BorderLayout.SOUTH);//加于南面
      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));//若typePanel中选择Confirm按钮,得messageTypePanel的内容
         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)
   {
      var g2 = (Graphics2D) g;
      var rect = new Rectangle2D.Double(0, 0, getWidth() - 1, getHeight() - 1);
      g2.setPaint(Color.YELLOW);//设置颜色
      g2.fill(rect);//进行填充
      g2.setPaint(Color.BLUE);
      g2.draw(rect);
   }

   public Dimension getPreferredSize()
   {
      return new Dimension(10, 10);
   }
}

  结果:

 

 

   测试程序4

    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。

  代码:

 

package dialog;

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

/**
 * @version 1.35 2018-04-10
 * @author Cay Horstmann
 */
public class DialogTest
{
   public static void main(String[] args)
   {
      EventQueue.invokeLater(() -> {
          DialogFrame frame = new DialogFrame();
         frame.setTitle("DialogTest");
         frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
         frame.setVisible(true);
      });
   }
}

 

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);//调用超类的构造器

      // 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));//可见

      // add OK button to southern border

       JPanel panel = new JPanel();
      panel.add(ok);
      add(panel, BorderLayout.SOUTH);

      pack();
   }
}
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();//菜单栏
      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));//退出
      fileMenu.add(exitItem);
   }
}

  结果:

 

   测试程序5

    在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。

  代码:

 

package dataExchange;

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

/**
 * @version 1.35 2018-04-10
 * @author Cay Horstmann
 */
public class DataExchangeTest
{
   public static void main(String[] args)
   {
      EventQueue.invokeLater(() -> {
         var frame = new DataExchangeFrame();
         frame.setTitle("DataExchangeTest");
         frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
         frame.setVisible(true);
      });
   }
}

 

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;
   }
}
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;//ok是boolean型的
   private JDialog dialog;

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

      // construct a panel with user name and password fields

      var panel = new JPanel();
      panel.setLayout(new GridLayout(2, 2));//网格布局,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);
      });

      var cancelButton = new JButton("Cancel");
      cancelButton.addActionListener(event -> dialog.setVisible(false));//调用取消按钮的添加监听器,设置组件不可见

      // add buttons to southern border

      var buttonPanel = new JPanel();
      buttonPanel.add(okButton);//加OK按钮
      buttonPanel.add(cancelButton);
      add(buttonPanel, BorderLayout.SOUTH);//南边
   }

   /**
    * 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;

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

      var mbar = new JMenuBar();
      setJMenuBar(mbar);
      var fileMenu = new JMenu("File");
      mbar.add(fileMenu);

      // add Connect and Exit menu items加入ConnectExit

      var connectItem = new JMenuItem("Connect");
      connectItem.addActionListener(new ConnectAction());
      fileMenu.add(connectItem);

      // the Exit item exits the program

      var 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");
         }
      }
   }
}

  结果:

 

 

  测试程序6

    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;

    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。

  代码:

 

package fileChooser;

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

/**
 * @version 1.26 2018-04-10
 * @author Cay Horstmann
 */
public class FileChooserTest
{
   public static void main(String[] args)
   {
      EventQueue.invokeLater(() -> {
         var frame = new ImageViewerFrame();
         frame.setTitle("FileChooserTest");
         frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
         frame.setVisible(true);
      });
   }
}

 

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)//getIcon获得文件类型的图标
   {
      if (!f.isDirectory() && filter.accept(f)) return icon;
      else return null;
   }
}
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));//setPreferredSize在布局管理器会获取空间的PreferredSize
      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
            var 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);//设置此文件或文件类型的图标
         }
      });
   }
}
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
      var menuBar = new JMenuBar();
      setJMenuBar(menuBar);

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

      var openItem = new JMenuItem("Open");
      menu.add(openItem);
      openItem.addActionListener(event -> {
         chooser.setCurrentDirectory(new File("."));//用setCurrentDirectory改变进程的当前目录

         // show file chooser dialog
            int result = chooser.showOpenDialog(ImageViewerFrame.this);//(不太理解)用showOpenDialog方法,显示打开文件的对话框
    
// 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();
            }
         });

      var 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 接受以jpg, .jpeg, .gif为扩展名的图像文件
      var 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")));
   }
}

 

 

  结果:

 

 测试程序7

    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;

    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。

  代码:

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);
       }); 
    }
}
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);//固定大小
  
       ColorChooserPanel panel = new ColorChooserPanel();
       add(panel);
    }
 }
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//实现接口
    {
       private JDialog dialog;//对话框
       private JColorChooser chooser;
  
       public ModelessListener()
       {
          chooser = new JColorChooser();
          dialog = JColorChooser.createDialog(ColorChooserPanel.this, "Background Color",
                false /* not modal */, chooser,
                event -> setBackground(chooser.getColor()),//getColor()设置颜色
                null /* no Cancel button listener */);
       }//不太理解
  
       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);
       }
    }
 }

 

  结果:

 

 

 

 

实验总结:     

    通过本次的实验,我了解了:    1.菜单组件用途及常用API                         2.对话框组件用途及常用API               

  3.练习设计简单应用程序的GUI

    本次实验难度较大,对于导入理解的程序在理解上困难比较大,有一些代码不明白,尤其是对话框,选项对话框的程序,添加注释很难,对于书上的解释也不太理解。通过本次实验,对于菜单,工具栏有了进一步的理解。通过阅读完整的代码,逐渐了解了菜单的完整使用过程及方法,对菜单有了更深的理解。在老师讲解知识后,要把不明白的程序要弄清楚,多多理解几次。

posted @ 2019-12-09 21:15  小Q布丁  阅读(190)  评论(1编辑  收藏  举报