新手上路多多帮忙
2004-07-03 17:25
337 查看
//新手上路多多帮忙
import java.applet.*;
import java.awt.*;
import java.awt.event.*;
public class listener extends Applet implements ActionListener,
MouseMotionListener{
int x=-1,y=-1,rubber=0,clear=0;
Color c = new Color(255,0,0);
int con=3;
Button redbutton,bluebutton,greenbutton,rubberbutton,clearbutton;
public void init()
{
addMouseMotionListener(this);
redbutton = new Button("红色");
bluebutton = new Button("蓝色");
greenbutton = new Button("绿色");
rubberbutton = new Button("橡皮");
clearbutton = new Button("清除");
add(redbutton);
add(bluebutton);
add(greenbutton);
add(rubberbutton);
add(clearbutton);
redbutton.addActionListener(this);
bluebutton.addActionListener(this);
greenbutton.addActionListener(this);
rubberbutton.addActionListener(this);
clearbutton.addActionListener(this);
setSize(640,480);
}
//paint方法
public void paint(Graphics g)
{
if(rubber==0&&clear==0)
{
g.setColor(c);
g.fillOval(x,y,con,con);
}//end of if
else if (rubber==1&&clear==0)
{
g.clearRect(x,y,10,10);
}
else if(rubber==0&&clear==1)
{
g.clearRect(0,0,getSize().width,getSize().height);
}
}
public void mouseDragged(MouseEvent e)
{
x=(int)e.getX();
y=(int)e.getY();
repaint();
}
public void mouseMove(MouseEvent e)
{
}
public void update(Graphics g)
{
paint(g);
}
public void actionPerformed(ActionEvent e)
{
if(e.getSource()==redbutton)
{
rubber=clear=0;
c=new Color(255,0,0);
}
else if(e.getSource()==bluebutton)
{
rubber=clear=0;
c=new Color(0,0,255);
}
else if(e.getSource()==greenbutton)
{
rubber=clear=0;
c = new Color(0,255,0);
}
else if(e.getSource()==rubberbutton)
{
rubber=1;
clear=0;
}
else if(e.getSource()==clearbutton)
{
rubber=0;
clear=1;
repaint();
}
}
}
//错误提示
F:/学校教学课件/JAVA/java/listener.java:4: listener
is not abstract and does not override abstract method mouseReleased(java.awt.event.MouseEvent)
in java.awt.event.MouseListener
public class listener extends Applet implements ActionListener,
import java.applet.*;
import java.awt.*;
import java.awt.event.*;
public class listener extends Applet implements ActionListener,
MouseMotionListener{
int x=-1,y=-1,rubber=0,clear=0;
Color c = new Color(255,0,0);
int con=3;
Button redbutton,bluebutton,greenbutton,rubberbutton,clearbutton;
public void init()
{
addMouseMotionListener(this);
redbutton = new Button("红色");
bluebutton = new Button("蓝色");
greenbutton = new Button("绿色");
rubberbutton = new Button("橡皮");
clearbutton = new Button("清除");
add(redbutton);
add(bluebutton);
add(greenbutton);
add(rubberbutton);
add(clearbutton);
redbutton.addActionListener(this);
bluebutton.addActionListener(this);
greenbutton.addActionListener(this);
rubberbutton.addActionListener(this);
clearbutton.addActionListener(this);
setSize(640,480);
}
//paint方法
public void paint(Graphics g)
{
if(rubber==0&&clear==0)
{
g.setColor(c);
g.fillOval(x,y,con,con);
}//end of if
else if (rubber==1&&clear==0)
{
g.clearRect(x,y,10,10);
}
else if(rubber==0&&clear==1)
{
g.clearRect(0,0,getSize().width,getSize().height);
}
}
public void mouseDragged(MouseEvent e)
{
x=(int)e.getX();
y=(int)e.getY();
repaint();
}
public void mouseMove(MouseEvent e)
{
}
public void update(Graphics g)
{
paint(g);
}
public void actionPerformed(ActionEvent e)
{
if(e.getSource()==redbutton)
{
rubber=clear=0;
c=new Color(255,0,0);
}
else if(e.getSource()==bluebutton)
{
rubber=clear=0;
c=new Color(0,0,255);
}
else if(e.getSource()==greenbutton)
{
rubber=clear=0;
c = new Color(0,255,0);
}
else if(e.getSource()==rubberbutton)
{
rubber=1;
clear=0;
}
else if(e.getSource()==clearbutton)
{
rubber=0;
clear=1;
repaint();
}
}
}
//错误提示
F:/学校教学课件/JAVA/java/listener.java:4: listener
is not abstract and does not override abstract method mouseReleased(java.awt.event.MouseEvent)
in java.awt.event.MouseListener
public class listener extends Applet implements ActionListener,