Java中的鼠标和键盘事件
1、使用MouseListener借口处理鼠标事件
鼠标事件有5种：按下鼠标键，释放鼠标键，点击鼠标键，鼠标进入和鼠标退出
鼠标事件类型是MouseEvent，主要方法有：
getX(),getY() 获取鼠标位置
getModifiers() 获取鼠标左键或者右键
getClickCount() 获取鼠标被点击的次数
getSource() 获取鼠标发生的事件源
事件源获得监视器的方法是addMouseListener()，移去监视器的方法是removeMouseListener()
处理事件源发生的时间的事件的接口是MouseListener 接口中有如下的方法
mousePressed(MouseEvent) 负责处理鼠标按下事件
mouseReleased(MouseEvent) 负责处理鼠标释放事件
mouseEntered(MouseEvent) 负责处理鼠标进入容器事件
mouseExited(MouseEvent) 负责处理鼠标离开事件
mouseClicked(MouseEvent) 负责处理点击事件
2、使用MouseMotionListener接口处理鼠标事件
事件源发生的鼠标事件有2种：拖动鼠标和鼠标移动
鼠标事件的类型是MouseEvent
事件源获得监视器的方法是addMouseMotionListener()
处理事件源发生的事件的接口是MouseMotionListener 接口中有如下的方法
mouseDragged() 负责处理鼠标拖动事件
mouseMoved() 负责处理鼠标移动事件
3、控制鼠标的指针形状
setCursor(Cursor.getPreddfinedCursor(Cursor.鼠标形状定义)) 鼠标形状定义见（书 P 210）
4、键盘事件
键盘事件源使用addKeyListener 方法获得监视器
键盘事件的接口是KeyListener 接口中有3个方法
public void keyPressed(KeyEvent e) 按下键盘按键
public void keyReleased(KeyEvent e) 释放键盘按键
public void keyTypde(KeyEvent e) 按下又释放键盘按键
package mouseenvent;
import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
public class Mouse extends JFrame implements MouseListener{
JPanel jp = new JPanel();
JLabel statusbar = new JLabel();
static final long serialVersionUID=0;
public Mouse(){
setTitle("Mouse Event");
getContentPane().add(jp,BorderLayout.CENTER);
getContentPane().add(statusbar, BorderLayout.SOUTH);
jp.addMouseListener(this);
}
public static void main(String[] args){
Mouse frame = new Mouse();
frame.setSize(500,500);
frame.setVisible(true);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
public void mousePressed(MouseEvent e){
int x = e.getX();
int y = e.getY();
String s = "鼠标在坐标"+"("+x+","+y+")"+"处按下";
statusbar.setText(s);
}
public void mouseReleased(MouseEvent e){
int x = e.getX();
int y = e.getY();
String s = "鼠标在坐标"+"("+x+","+y+")"+"处释放";
statusbar.setText(s);
}
public void mouseClicked(MouseEvent e){
int x = e.getX();
int y = e.getY();
String s = "鼠标在坐标"+"("+x+","+y+")"+"处点击";
statusbar.setText(s);
}
public void mouseEntered(MouseEvent e){
int x = e.getX();
int y = e.getY();
String s = "鼠标在坐标"+"("+x+","+y+")"+"处进入";
statusbar.setText(s);
}
public void mouseExited(MouseEvent e){
int x = e.getX();
int y = e.getY();
String s = "鼠标在坐标"+"("+x+","+y+")"+"处离开";
statusbar.setText(s);
}
}
package mouseenvent;
import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
public class MouseMotion extends JFrame implements MouseMotionListener{
static final long serialVersionUID=0;
JLabel bar = new JLabel();
JTextField text = new JTextField();
public MouseMotion(){
setTitle("Mouse Event");
getContentPane().add(text,BorderLayout.NORTH);
getContentPane().add(bar, BorderLayout.SOUTH);
addMouseMotionListener(this);
}
public void mousePressed(MouseEvent e){
int x = e.getX();
int y = e.getY();
String s = "x = "+x+"y = "+y;
bar.setText(s);
text.setText(s);
}
public void mouseDragged(MouseEvent e){
int x = e.getX();
int y = e.getY();
String s = "x = "+x+" y = "+y;
bar.setText(s);
text.setText(s);
}
public void mouseMoved(MouseEvent e){
int x = e.getX();
int y = e.getY();
String s = "x = "+x+" y = "+y;
bar.setText(s);
text.setText(s);
}
public static void main(String args[])throws Exception{
MouseMotion mouse = new MouseMotion();
mouse.setSize(500,500);
mouse.setVisible(true);
mouse.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
}
package mouseenvent;
import java.awt.event.*;
import javax.swing.*;
import java.awt.*;
public class Key extends JFrame implements KeyListener{
JLabel bar ;
public Key(){
bar = new JLabel();
getContentPane().add(bar,BorderLayout.CENTER);
addKeyListener(this);
}
public void keyPressed(KeyEvent e){
char c = e.getKeyChar();
String s = c+"" ;
bar.setText(s);
}
public void keyReleased(KeyEvent e){
char c = e.getKeyChar();
}
public void keyTyped(KeyEvent e){
char c = e.getKeyChar();
}
public static void main(String args[])throws Exception{
Key key = new Key();
key.setSize(500,500);
key.setVisible(true);
key.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
}
}
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