201771010110孔维滢《面向对象程序设计（java）》第十三周学习总结(代码片段)

package button;

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

/**
 * @version 1.34 2015-06-12
 * @author Cay Horstmann
 */
public class ButtonTest

   public static void main(String[] args)
   
      EventQueue.invokeLater(() -> 
         JFrame frame = new ButtonFrame();//构建一个ButtonFrame类对象
         frame.setTitle("ButtonTest");//设置Title属性，确定框架标题栏中的文字
         frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);//设置默认关闭操作，退出并关闭
         frame.setVisible(true);//设置Visible属性，组件可见
      );
   

package button;

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

/**
 * A frame with a button panel
 */
public class ButtonFrame extends JFrame

   private JPanel buttonPanel;
   private static final int DEFAULT_WIDTH = 300;
   private static final int DEFAULT_HEIGHT = 200;

   public ButtonFrame()
         
      setSize(DEFAULT_WIDTH, DEFAULT_HEIGHT);

      // 创建按钮
      JButton yellowButton = new JButton("Yellow");
      JButton blueButton = new JButton("Blue");
      JButton redButton = new JButton("Red");

      buttonPanel = new JPanel();

      // 添加按钮到面板
      buttonPanel.add(yellowButton);//调用add方法将按钮添加到面板
      buttonPanel.add(blueButton);
      buttonPanel.add(redButton);

      // 添加面板到框架
      add(buttonPanel);

      // 创建按钮事件
      ColorAction yellowAction = new ColorAction(Color.YELLOW);
      ColorAction blueAction = new ColorAction(Color.BLUE);
      ColorAction redAction = new ColorAction(Color.RED);

      // 将时间与按钮关联
      yellowButton.addActionListener(yellowAction);
      blueButton.addActionListener(blueAction);
      redButton.addActionListener(redAction);
   

   /**
    * An action listener that sets the panel‘s background color.
    */
   private class ColorAction implements ActionListener//实现了ActionListener的接口类
   
      private Color backgroundColor;

      public ColorAction(Color c)
      
         backgroundColor = c;
      

      public void actionPerformed(ActionEvent event)//actionListener方法接收一个ActionEvent对象参数
      
         buttonPanel.setBackground(backgroundColor);
      
   

package plaf;

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

/**
 * @version 1.32 2015-06-12
 * @author Cay Horstmann
 */
public class PlafTest

   public static void main(String[] args)
   
      EventQueue.invokeLater(() -> 
         JFrame frame = new PlafFrame();//构建一个PlafFrame类对象
         frame.setTitle("PlafTest");//设置Title属性，确定框架标题栏中的文字
         frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);//设置默认关闭操作，退出并关闭
         frame.setVisible(true);//设置Visible属性，组件可见
      );
   

package plaf;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
import javax.swing.UIManager;

/**
 * A frame with a button panel for changing look-and-feel
 */
public class PlafFrame extends JFrame

   private JPanel buttonPanel;

   public PlafFrame()
   
      buttonPanel = new JPanel();

      UIManager.LookAndFeelInfo[] infos = UIManager.getInstalledLookAndFeels();//获得一个用于描述已安装的观感实现的对象数组
      for (UIManager.LookAndFeelInfo info : infos)
         makeButton(info.getName(), info.getClassName());//返回观感的显示名称，返回观感实现类的名称

      add(buttonPanel);
      pack();
   

   /**
    * Makes a button to change the pluggable look-and-feel.
    * @param name the button name
    * @param className the name of the look-and-feel class
    */
   private void makeButton(String name, String className)
   
	   // 添加按钮到面板

      JButton button = new JButton(name);
      buttonPanel.add(button);

      // 设置按钮事件

      button.addActionListener(event -> 
         // 按钮动作:切换到新的外观
         try
         
            UIManager.setLookAndFeel(className);
            SwingUtilities.updateComponentTreeUI(this);
            pack();
         
         catch (Exception e)
         
            e.printStackTrace();
         
      );
   //使用辅助方法makeButton和匿名内部类指定按钮动作

package action;

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

/**
 * @version 1.34 2015-06-12
 * @author Cay Horstmann
 */
public class ActionTest

   public static void main(String[] args)
   
      EventQueue.invokeLater(() -> 
         JFrame frame = new ActionFrame();//构建一个ActionFrame类对象
         frame.setTitle("ActionTest");//设置Title属性，确定框架标题栏中的文字
         frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);//设置默认关闭操作，退出并关闭
         frame.setVisible(true);//设置Visible属性，组件可见
      );
   

package action;

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

/**
 * A frame with a panel that demonstrates color change actions.
 */
public class ActionFrame extends JFrame

   private JPanel buttonPanel;
   private static final int DEFAULT_WIDTH = 300;
   private static final int DEFAULT_HEIGHT = 200;

   public ActionFrame()
   
      setSize(DEFAULT_WIDTH, DEFAULT_HEIGHT);

      buttonPanel = new JPanel();

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

      // 为这些操作添加按钮
      buttonPanel.add(new JButton(yellowAction));
      buttonPanel.add(new JButton(blueAction));
      buttonPanel.add(new JButton(redAction));

      // 将面板添加到框架
      add(buttonPanel);

      // 将Y、B和R键与名称关联起来
      InputMap imap = buttonPanel.getInputMap(JComponent.WHEN_ANCESTOR_OF_FOCUSED_COMPONENT);//获得将按键映射到动作键的输入映射
      imap.put(KeyStroke.getKeyStroke("ctrl Y"), "panel.yellow");//根据一个便于人们阅读的说明创建一个按钮（由空格分隔的字符串序列）
      imap.put(KeyStroke.getKeyStroke("ctrl B"), "panel.blue");
      imap.put(KeyStroke.getKeyStroke("ctrl R"), "panel.red");

      // 将名称与操作关联起来
      ActionMap amap = buttonPanel.getActionMap();//返回关联动作映射键和动作对象的映射
      amap.put("panel.yellow", yellowAction);
      amap.put("panel.blue", blueAction);
      amap.put("panel.red", redAction);
   
   
   public class ColorAction extends AbstractAction
   
      /**
       * Constructs a color action.
       * @param name the name to show on the button
       * @param icon the icon to display on the button
       * @param c the background color
       */
      public ColorAction(String name, Icon icon, Color c)
      
         putValue(Action.NAME, name);//将名/值放置在动作对象内
         putValue(Action.SMALL_ICON, icon);
         putValue(Action.SHORT_DESCRIPTION, "Set panel color to " + name.toLowerCase());
         putValue("color", c);
      

      public void actionPerformed(ActionEvent event)
      
         Color c = (Color) getValue("color");//返回被存储的名对的值
         buttonPanel.setBackground(c);
      
   

package mouse;

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

/**
 * @version 1.34 2015-06-12
 * @author Cay Horstmann
 */
public class MouseTest

   public static void main(String[] args)
   
      EventQueue.invokeLater(() -> 
         JFrame frame = new MouseFrame();//构建一个MouseFrame类对象
         frame.setTitle("MouseTest");//设置Title属性，确定框架标题栏中的文字
         frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);//设置默认关闭操作，退出并关闭
         frame.setVisible(true);//设置Visible属性，组件可见
      );
   

package mouse;

import javax.swing.*;

/**
 * A frame containing a panel for testing mouse operations
 */
public class MouseFrame extends JFrame

   public MouseFrame()
   
      add(new MouseComponent());
      pack();
   

package mouse;

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

/**
 * A component with mouse operations for adding and removing squares.
 */
public class MouseComponent extends JComponent

   private static final int DEFAULT_WIDTH = 300;
   private static final int DEFAULT_HEIGHT = 200;

   private static final int SIDELENGTH = 10;
   private ArrayList<Rectangle2D> squares;
   private Rectangle2D current; // 包含鼠标光标的正方形

   public MouseComponent()
   
      squares = new ArrayList<>();
      current = null;

      addMouseListener(new MouseHandler());
      addMouseMotionListener(new MouseMotionHandler());
   

   public Dimension getPreferredSize()  return new Dimension(DEFAULT_WIDTH, DEFAULT_HEIGHT);    
   
   public void paintComponent(Graphics g)
   
      Graphics2D g2 = (Graphics2D) g;

      // 画出所有方块
      for (Rectangle2D r : squares)
         g2.draw(r);
   

   /**
    * Finds the first square containing a point.
    * @param p a point
    * @return the first square that contains p
    */
   public Rectangle2D find(Point2D p)
   
      for (Rectangle2D r : squares)
      
         if (r.contains(p)) return r;
      
      return null;
   

   /**
    * Adds a square to the collection.
    * @param p the center of the square
    */
   public void add(Point2D p)
   
      double x = p.getX();
      double y = p.getY();

      current = new Rectangle2D.Double(x - SIDELENGTH / 2, y - SIDELENGTH / 2, SIDELENGTH,
            SIDELENGTH);
      squares.add(current);
      repaint();
   

   /**
    * Removes a square from the collection.
    * @param s the square to remove
    */
   public void remove(Rectangle2D s)
   
      if (s == null) return;
      if (s == current) current = null;
      squares.remove(s);
      repaint();
   

   private class MouseHandler extends MouseAdapter
   
      public void mousePressed(MouseEvent event)
      
         // 如果光标不在正方形内，则添加一个新的正方形
         current = find(event.getPoint());
         if (current == null) add(event.getPoint());
      

      public void mouseClicked(MouseEvent event)
      
         // 如果双击，则删除当前方块
         current = find(event.getPoint());
         if (current != null && event.getClickCount() >= 2) remove(current);
      
   

   private class MouseMotionHandler implements MouseMotionListener
   
      public void mouseMoved(MouseEvent event)
      
         // 如果鼠标指针在内部，则将其设置为十字线
         // 一个矩形

         if (find(event.getPoint()) == null) setCursor(Cursor.getDefaultCursor());
         else setCursor(Cursor.getPredefinedCursor(Cursor.CROSSHAIR_CURSOR));
      

      public void mouseDragged(MouseEvent event)
      
         if (current != null)
         
            int x = event.getX();
            int y = event.getY();

            // 拖动当前矩形到(x, y)的中心
            current.setFrame(x - SIDELENGTH / 2, y - SIDELENGTH / 2, SIDELENGTH, SIDELENGTH);
            repaint();
         
      
      

import java.util.*;
import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
import java.awt.Frame;
import java.io.File;
import java.io.FileNotFoundException;

public class Dianmingqi extends JFrame implements ActionListener 
	private JButton but;

	private JButton show;
	private static boolean flag = true;

	public static void main(String arguments[]) 
		new Dianmingqi();

	

	public Dianmingqi() 

		but = new JButton("START");
		but.setBounds(100, 150, 100, 40);

		show = new JButton("开始点名");
		show.setBounds(80, 80, 180, 30);
		show.setFont(new Font("宋体", Font.BOLD, 30));

		add(but);

		add(show);

		setLayout(null);// 布局管理器必须先初始化为空才能赋值
		setVisible(true);
		setResizable(false);
		setBounds(100, 100, 300, 300);
        //setBackground(Color.red);不起作用
		this.getContentPane().setBackground(Color.cyan);
		setTitle("START");
		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

		but.addActionListener(this);
	

	public void actionPerformed(ActionEvent e) 
		int i = 0;
		String names[] = new String[50];
		try 
			Scanner in = new Scanner(new File("studentnamelist.txt"));
			while (in.hasNextLine()) 
				names[i] = in.nextLine();
				i++;
			
		 catch (FileNotFoundException e1) 

			e1.printStackTrace();
		

		if (but.getText() == "START") 

			show.setBackground(Color.BLUE);
			flag = true;
			new Thread() 
				public void run() 
					while (Dianmingqi.flag) 
						Random r = new Random();
						int i = r.nextInt(47);
						show.setText(names[i]);
					
				
			.start();
			but.setText("STOP");// 更改文本内容
			but.setBackground(Color.YELLOW);
		 else if (but.getText() == "STOP") 
			flag = false;
			but.setText("START");
			but.setBackground(Color.WHITE);
			show.setBackground(Color.GREEN);