2019.11.14

Posted 2021-03-17 quan-2723365710

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动作事件
1、P255例13.22，以及P256例13.23，注意比较用普通当前类和匿名内部类两种方式实现按钮对象的事件监听器。（必做题，20分）

代码1：
package MyAdvancedEvent;

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

import MyAdvancedEvent.SimpleEvent.jbAction;

public class SimpleEvents extends JFrame implements ActionListener{
    private JButton jb=new JButton("我是按钮，单击我");
    public SimpleEvents() {
        setLayout(null);
        setBounds(100,100,300,300);
        setVisible(true);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        add(jb);
        jb.setBounds(10, 10, 150, 30);
        jb.addActionListener(this);
    }
    public void actionPerformed(ActionEvent e) {
        jb.setText("我被单击了");
    }
    public static void main(String[] args) {
        new SimpleEvents();
    }
}
代码2：
package MyAdvancedEvent;

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

import MyAdvancedEvent.SimpleEvent.jbAction;

public class SimpleEvent2 extends JFrame{
    private JButton jb=new JButton("我是按钮，单击我");
    public SimpleEvent2() {
        setLayout(null);
        setBounds(100,100,300,300);
        setVisible(true);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        add(jb);
        jb.setBounds(10, 10, 150, 30);
        jb.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                jb.setText("我被单击了");
            }
        });
    }
    public static void main(String[] args) {
        new SimpleEvent2();
    }
}

运行截图:
技术图片

鼠标事件
1、P460【例25.2】一个用来演示鼠标事件的典型示例MouseEvent_Example（必做题，20分）

代码：
package MyAdvancedEvent;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;

import javax.swing.*;
public class MouseEvent1 {
    JFrame f;
    JLabel l;
    public MouseEvent1() {
        f=new JFrame();
        l=new JLabel();
        f.add(l);
        l.addMouseListener(new MouseListener() {
            public void mouseClicked(MouseEvent e) {
                System.out.print("单击了鼠标按键，");
                int i=e.getButton();
                if(i==MouseEvent.BUTTON1) {
                    System.out.println("单击的是鼠标左键，");
                }
                if(i==MouseEvent.BUTTON2) {
                    System.out.println("单击的是鼠标滚轮，");
                }
                if(i==MouseEvent.BUTTON3) {
                    System.out.println("单击的是鼠标右键键，");
                }
                int clickcount=e.getClickCount();
                System.out.println("单击次数为"+clickcount+"下");
            }
            public void mousePressed(MouseEvent e) {
                System.out.print("鼠标按键被按下，");
                int i=e.getButton();
                if(i==MouseEvent.BUTTON1) {
                    System.out.println("按下的是鼠标左键，");
                }
                if(i==MouseEvent.BUTTON2) {
                    System.out.println("按下的是鼠标滚轮，");
                }
                if(i==MouseEvent.BUTTON3) {
                    System.out.println("按下的是鼠标右键键，");
                }
            }
            public void mouseReleased(MouseEvent e) {
                System.out.print("鼠标按键被释放，");
                int i=e.getButton();
                if(i==MouseEvent.BUTTON1) {
                    System.out.println("释放的是鼠标左键，");
                }
                if(i==MouseEvent.BUTTON2) {
                    System.out.println("释放的是鼠标滚轮，");
                }
                if(i==MouseEvent.BUTTON3) {
                    System.out.println("释放的是鼠标右键键，");
                }
            }
            public void mouseEntered(MouseEvent e) {
                System.out.println("光标移入组件");
            }
            public void mouseExited(MouseEvent e) {
                System.out.println("光标移入组件");
            }
            
        });
        f.setBounds(100, 100, 200, 200);
        f.setVisible(true);
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    }
    public static void main(String[] args) {
        new MouseEvent1();
    }
}

运行截图：
技术图片

2、鼠标选色卡MouseEventColor，运行结果如下，通过鼠标点击不同的颜色，将窗体的背景色设置成不同。试用普通类、匿名内部类、鼠标适配器三种方式分别实例化监听器对象。
（必做题，20分）
技术图片

代码1：
package MyAdvancedEvent;
import java.awt.Color;
import java.awt.Font;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;

import javax.swing.*;
public class MouseEventColor implements MouseListener{
    JFrame f;
    JPanel p;
    Box box;
    JButton[]Button=new JButton[7];
    Color[]color= {Color.CYAN,Color.BLUE,Color.GRAY,Color.DARK_GRAY,Color.MAGENTA,Color.YELLOW,Color.PINK};
    public MouseEventColor() {
        f=new JFrame("选");
        p=new JPanel();
        box=Box.createHorizontalBox();
        for(int i=0;i<7;i++) {
            Button[i]=new JButton("  ");
            Button[i].setBackground(color[i]);
            Button[i].setFont(new Font("",Font.PLAIN,15));
            Button[i].addMouseListener(this);
            box.add(Button[i]);
        }
        p.add(box);
        f.add(p);
        f.setBounds(100, 100, 310, 300);
        f.setVisible(true);
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    }
    public static void main(String[] args) {
        new MouseEventColor();
    }
        public void mouseClicked(MouseEvent e) {
            if(e.getSource()==Button[0]) {
                p.setBackground(color[0]);
            }else if(e.getSource()==Button[1]) {
                p.setBackground(color[1]);
            }else if(e.getSource()==Button[2]) {
                p.setBackground(color[2]);
            }else if(e.getSource()==Button[3]) {
                p.setBackground(color[3]);
            }else if(e.getSource()==Button[4]) {
                p.setBackground(color[4]);
            }else if(e.getSource()==Button[5]) {
                p.setBackground(color[5]);
            }else{
                p.setBackground(color[6]);
            }
        }
        public void mousePressed(MouseEvent e) {
            
        }
        public void mouseReleased(MouseEvent e) {
            
        }
        public void mouseEntered(MouseEvent e) {
            
        }
        public void mouseExited(MouseEvent e) {
            
        }
    
}
代码2：
package MyAdvancedEvent;
import java.awt.Color;
import java.awt.Font;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;

import javax.swing.*;
public class MouseEventColor1 {
    JFrame f;
    JPanel p;
    Box box;
    JButton[]Button=new JButton[7];
    Color[]color= {Color.CYAN,Color.BLUE,Color.GRAY,Color.DARK_GRAY,Color.MAGENTA,Color.YELLOW,Color.PINK};
    public MouseEventColor1() {
        f=new JFrame("选");
        p=new JPanel();
        box=Box.createHorizontalBox();
        for(int i=0;i<7;i++) {
            Button[i]=new JButton("  ");
            Button[i].setBackground(color[i]);
            Button[i].setFont(new Font("",Font.PLAIN,15));
            Button[i].addMouseListener(new MouseListener() {
                public void mouseClicked(MouseEvent e) {
                    if(e.getSource()==Button[0]) {
                        p.setBackground(color[0]);
                    }else if(e.getSource()==Button[1]) {
                        p.setBackground(color[1]);
                    }else if(e.getSource()==Button[2]) {
                        p.setBackground(color[2]);
                    }else if(e.getSource()==Button[3]) {
                        p.setBackground(color[3]);
                    }else if(e.getSource()==Button[4]) {
                        p.setBackground(color[4]);
                    }else if(e.getSource()==Button[5]) {
                        p.setBackground(color[5]);
                    }else{
                        p.setBackground(color[6]);
                    }
                }
                public void mousePressed(MouseEvent e) {
                    
                }
                public void mouseReleased(MouseEvent e) {
                    
                }
                public void mouseEntered(MouseEvent e) {
                    
                }
                public void mouseExited(MouseEvent e) {
                    
                }
            });
            box.add(Button[i]);
        }
        p.add(box);
        f.add(p);
        f.setBounds(100, 100, 310, 300);
        f.setVisible(true);
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    }
    public static void main(String[] args) {
        new MouseEventColor1();
    }
}
代码3：
package MyAdvancedEvent;
import java.awt.Color;
import java.awt.Font;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;

import javax.swing.*;
public class MouseEventColor3 {
    JFrame f;
    JPanel p;
    Box box;
    Color[]color= {Color.CYAN,Color.BLUE,Color.GRAY,Color.DARK_GRAY,Color.MAGENTA,Color.YELLOW,Color.PINK};
    public MouseEventColor3() {
        f=new JFrame("");
        p=new JPanel();
        box=Box.createHorizontalBox();
        for(int i=0;i<color.length;i++) {
            final JButton button=new JButton(" ");
            button.setBackground(color[i]);
            button.setFont(new Font("",Font.PLAIN,15));
            button.addMouseListener(new MouseAdapter() {
                public void mouseClicked(MouseEvent e) {
                        p.setBackground(button.getBackground());
                }
            });
            box.add(button);
        }
        p.add(box);
        f.add(p);
        f.setBounds(100, 100, 310, 300);
        f.setVisible(true);
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    }
    public static void main(String[] args) {
        new MouseEventColor3();
    }
}

运行截图：
技术图片

3、鼠标事件响应练习MouseEventapp.java。当鼠标进入窗口时，窗口的标题显示“欢迎”；当鼠标离开窗口时，窗口的标题显示“再见”；鼠标在窗体单击时，就在鼠标单击所在位置显示“开始”。（必做题，20分）
技术图片

代码：
package MyAdvancedEvent;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;

import javax.swing.*;
public class MouseEventapp {
    JFrame f;
    JLabel l;
    public MouseEventapp() {
        f=new JFrame("再见！");
        l=new JLabel("开始");
        f.add(l);
        l.setVisible(false);
        f.addMouseListener(new MouseAdapter() {
            public void mouseClicked(MouseEvent e) {
                l.setVisible(true);
                int x=e.getX(),y=e.getY()-30;
                l.setBounds(x, y, 100, 20);
            }
            public void mouseEntered(MouseEvent e) {
                f.setTitle("欢迎！");
            }
            public void mouseExited(MouseEvent e) {
                f.setTitle("再见！");
                l.setVisible(false);
            }
        });
        f.setBounds(200, 200, 300, 300);
        f.setVisible(true);
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    }
    public static void main(String[] args) {
        new MouseEventapp();
    }
}

运行截图：
技术图片

2、鼠标移动监听练习MyMouseMotionListener.java。当鼠标在窗体内移动和拖动时，分别显示如下信息：最前面是移动或拖动次数；最后面的是发生事件时鼠标所在的x坐标和y坐标（选做题，20分）
技术图片

代码：
package MyAdvancedEvent;
import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseEvent;
import java.awt.event.MouseMotionListener;
import javax.swing.*;

public class MyMouseMotionLister {
    JFrame f;
    JLabel l;
    JButton b;
    JTextArea ta;
    JScrollPane sp;
    int count;
    public MyMouseMotionLister() {
        f=new JFrame("MyMouseMotionLister");
        l=new JLabel("click and drag the mouse");
        b=new JButton("退出");
        ta=new JTextArea();
        sp=new JScrollPane(ta);
        sp.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);
        f.add(l,BorderLayout.NORTH);
        f.add(sp,BorderLayout.CENTER);
        f.add(b,BorderLayout.SOUTH);
        f.setSize(400, 300);
        f.setVisible(true);
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        ta.addMouseMotionListener(new MouseMotionListener() {
            public void mouseDragged(MouseEvent e) {
                int xx=e.getX(),yy=e.getY();
                count++;
                String counts=count+"",x=xx+"",y=yy+"";
                String content=counts+"the mouse is drag:x="+x+",y="+y;
                ta.append(content+"
");
            }
            public void mouseMoved(MouseEvent e) {
                int xx=e.getX(),yy=e.getY();
                count++;
                String counts=count+"",x=xx+"",y=yy+"";
                String content=counts+"the mouse is moving:x="+x+",y="+y;
                ta.append(content+"
");
            }
        });
        b.addActionListener(new ActionListener(){
            public void actionPerformed(ActionEvent e){
                if(e.getSource()==b){
                    System.exit(0);
                }
            }
        });
    }
    public static void main(String[] args){
        new MyMouseMotionLister();
    }
}

运行截图：
技术图片

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