在applet中如何弹出对话框

新近写的一本书上的例子import java.io.*;
import java.awt.*;public class all extends Frame
{
Button butupdata, butnew,butdelete ,done;

   Updatarec updata;
   Newrec newrec;
   Deleterec deleterec;

   RandomAccessFile file;
   record data;
   int account;

    public all()
    {
     super("Transaction Processor");

     data=new record();

     try

     {
     file=new RandomAccessFile("credit.dat","rw");
     }
     catch(IOException e)
     {
     System.err.print("Can not find file"+e.toString());
     System.exit(1);
     }

     setup();
     }

     public void setup()
     {
      resize(300,80);
      setLayout(new GridLayout(2,2));

      butupdata=new Button("Updata record");
      butnew=new Button("New record");
      butdelete=new Button("Delete record");
      done=new Button("Done");

      add(butupdata);
      add(butnew);
      add(butdelete);
      add(done);

      show();

      updata=new Updatarec(file);
      newrec=new Newrec(file);
      deleterec=new Deleterec(file);

      }



       public void cleanup()
  {
   try
   {
   file.close();
   }
     catch(IOException e)
     {
     System.err.print("File can not close properly"+e.toString());
     System.exit(1);
     }
   }


   public boolean handleEvent(Event event)
   {


   if(event.id==Event.WINDOW_DEICONIFY||event.target==done)
   {
   cleanup();

   hide();
   dispose();
   System.exit(0);
   return true;
   }

   if(event.target instanceof Button)
   {
   if(event.arg.equals("Updata record"))
   {
   updata.show();
   return true;
   }

   if(event.arg.equals("New record"))
   {
   newrec.show();
   return true;
   }


        if(event.arg.equals("Delete record"))
   {
   deleterec.show();
   return true;
   }
   }

   return super.handleEvent(event);
   }



   public static void main(String args[])
  {
   System.out.println("Starting...");
   all accounts=new all();
   }
}

class Updatarec extends Dialog
{
RandomAccessFile file;
TextField acct,fname,lname,bal,transaction;
Label labacct,labfname,lablname,labbal,labtran;

Button cancel,save;

record data;
int account;

public Updatarec(RandomAccessFile f)
{
super(new Frame(),"Updata Record",true);
resize(300,180);
setLayout(new GridLayout(6,2));
file=f;

acct=new TextField(10);
fname=new TextField(10);
lname=new TextField(10);
bal=new TextField(10);
transaction=new TextField(10);

labacct=new Label("Account");
labfname=new Label("First name");
lablname=new Label("Last name");
labbal=new Label("Balance");
labtran=new Label("Transaction amount");
save=new Button("Save change");
cancel=new Button("Cancel");

add(labacct);add(acct);
add(labfname);add(fname);
add(lablname);add(lname);
add(labbal);add(bal);
add(labtran);add(transaction);
add(save);add(cancel);

data=new record();
}
public boolean action(Event event,Object o)
{
if(event.target==acct)
{
account=Integer.parseInt(acct.getText());

if(account<1||account>100)
{
acct.setText("Invalid account");
return true;
}

try
{
file.seek((account-1)*data.size());
data.read(file);
}
catch(IOException e)
     {
      acct.setText("Error reading file");
      }

     if(data.account!=0)
     {
      acct.setText(String.valueOf(data.account));
      fname.setText(data.fname);
      lname.setText(data.lname);
      bal.setText(String.valueOf(data.balance));
      transaction.setText("change(+) or payment(-)");
    }
     else
      acct.setText(String.valueOf(account)+"does not exist");

    }
     else if(event.target==transaction)
     {
      Double trans=Double.valueOf(transaction.getText());
      data.balance+=trans.doubleValue();
      bal.setText(String.valueOf(data.balance));
      }
     else if(event.target==save)
     {
      try{
      file.seek((account-1)*data.size());
      data.write(file);
      }
      catch(IOException e)
      {
      acct.setText("Error writing file");
      return true;
      }
      hide();
      clear();
      }

     else if(event.target==cancel)
     {
      hide();
      clear();
      }

return true;
}

private void clear()
{
acct.setText("");
fname.setText("");
lname.setText("");
bal.setText("");
transaction.setText("");
}

}

class Newrec extends Dialog{

       RandomAccessFile file;
       TextField acct,fname,lname,bal;
       Label labacct,labfname,lablname,labbal;
       Button cancel,save;

       record data;
       int account;

       public Newrec(RandomAccessFile f)
       {
       super(new Frame(),"New record",true);
       resize(300,150);
       setLayout(new GridLayout(5,2));
       file=f;

       acct=new TextField(10);
fname=new TextField(10);
lname=new TextField(10);
bal=new TextField(10);

labacct=new Label("Account");
labfname=new Label("First name");
lablname=new Label("Last name");
labbal=new Label("Balance");
save=new Button("Save change");
cancel=new Button("Cancel");

add(labacct);
add(acct);
add(labfname);
add(fname);
add(lablname);
add(lname);
add(labbal);
add(bal);
add(save);
add(cancel);

data=new record();
       }


       public boolean action(Event event,Object o)
       {

          if(event.target==acct)
{
account=Integer.parseInt(acct.getText());

if(account<1||account>100)
{
acct.setText("Invalid account");
return true;
}

   try
    {
file.seek((account-1)*data.size());
data.read(file);
}
   catch(IOException e)
        {
      acct.setText("Error reading file");
      }

      if(data.account==0)
        {
         fname.setText("Enter first name");
         lname.setText("Enter last name");
         bal.setText("Enter balance");
         }
        else
        {
         acct.setText(String.valueOf(data.account)+"already exist");
         fname.setText("");
         lname.setText("");
         bal.setText("");
         }
       }
            else if(event.target==save)
            {
             try{
             data.account=account;
             data.lname=lname.getText();
             data.fname=fname.getText();
             data.balance=(Double.valueOf(bal.getText())).doubleValue();
             file.seek((account-1)*data.size());
             data.write(file);
             }
             catch(IOException e)
             {
             acct.setText("Error writing file");
             return true;
             }
              hide();
              clear();
             }

           else if(event.target==cancel)
           {
           hide();
           clear();
           }
             return true;
            }


        private void clear()
  {
acct.setText("");
fname.setText("");
lname.setText("");
bal.setText("");
}

       }

import java.awt.*;
import javax.swing.*;
import java.awt.event.*;/*
<APPLET
CODE=dialoginput.class
WIDTH=300
HEIGHT=200>
</APPLET>
*/public class dialoginput extends JApplet implements ActionListener
{
JLabel top=new JLabel("Welcome to cn-java net !");
JButton display=new JButton("»áÔ±µÇÂ¼");
JLabel welcomeword=new JLabel(" Äú»¹Ã»ÓÐµÇÂ¼ ");JLabel title=new JLabel(" µÇ Â¼ ´° ¿Ú "),
name=new JLabel("»áÔ±Ãû:"),
password=new JLabel("ÃÜÂë:");
JTextField inputname=new JTextField(12);
JPasswordField inputpassword=new JPasswordField(12);//ÓëAWT²»Í¬µÄÊÇ,SwingÓÐÒ»¸öÓÃÓÚ¿ÚÁîµÄÌØÊâ¿Ø¼þ,¾ÍÊÇJPasswordField
JButton ok=new JButton("È·¶¨"),
cancel=new JButton("·ÅÆú");
private JDialog dialog=new JDialog((Frame)null,"µÇÂ¼",true);public void init()
{
Container contentPane=getContentPane();
Container dialogContentPane=dialog.getContentPane();
JPanel p=new JPanel();contentPane.setLayout(new GridBagLayout());
GridBagConstraints gbc=new GridBagConstraints();
gbc.gridy=0;
contentPane.add(top,gbc);
gbc.gridx=GridBagConstraints.RELATIVE;
gbc.gridy=1;
contentPane.add(display,gbc);
gbc.gridx=GridBagConstraints.RELATIVE;
gbc.gridy=2;
contentPane.add(welcomeword,gbc);
dialogContentPane.setLayout(new GridBagLayout());
GridBagConstraints gbb=new GridBagConstraints();gbb.gridx=1;
gbb.gridy=0;
dialogContentPane.add(title,gbb);
gbb.gridx=GridBagConstraints.RELATIVE;
gbb.gridy=1;
dialogContentPane.add(name,gbb);
dialogContentPane.add(inputname,gbb);gbb.gridx=GridBagConstraints.RELATIVE;
gbb.gridy=2;
dialogContentPane.add(password,gbb);
dialogContentPane.add(inputpassword,gbb);
inputpassword.setEchoChar('*'); gbb.gridx=GridBagConstraints.RELATIVE;
gbb.gridy=3;
p.setLayout(new FlowLayout());p.add(ok);
p.add(cancel);gbb.gridx=1;
gbb.gridy=4;dialogContentPane.add(p,gbb);
display.addActionListener(this);
ok.addActionListener(this);
cancel.addActionListener(this);
}public void actionPerformed(ActionEvent e)
{
if(e.getSource()==display){
dialog.setBounds(200,200,300,200);
dialog.show();
}else if(e.getSource()==ok){
welcomeword.setText("ÄúºÃ,"+inputname.getText()+",»¶Ó¹âÁÙÖÐÎÄJava¼¼ÊõÍø!");
}else if(e.getSource()==cancel){
welcomeword.setText("ÄãÃ»ÓÐÊäÈë!");
}
dialog.setVisible(false);
}
}

import java.awt.*;
import javax.swing.*;
import java.awt.event.*;/*
<APPLET
CODE=dialoginput.class
WIDTH=300
HEIGHT=200>
</APPLET>
*/public class dialoginput extends JApplet implements ActionListener
{
JLabel top=new JLabel("Welcome to cn-java net !");
JButton display=new JButton("会员登录");
JLabel welcomeword=new JLabel(" 您还没有登录 ");JLabel title=new JLabel(" 登录窗口 "),
name=new JLabel("会员名:"),
password=new JLabel("密码:");
JTextField inputname=new JTextField(12);
JPasswordField inputpassword=new JPasswordField(12);//与AWT不同的是,Swing有一个用于口令的特殊控件,就是JPasswordField
JButton ok=new JButton("确定"),
cancel=new JButton("放弃");
private JDialog dialog=new JDialog((Frame)null,"登录",true);public void init()
{
Container contentPane=getContentPane();
Container dialogContentPane=dialog.getContentPane();
JPanel p=new JPanel();contentPane.setLayout(new GridBagLayout());
GridBagConstraints gbc=new GridBagConstraints();
gbc.gridy=0;
contentPane.add(top,gbc);
gbc.gridx=GridBagConstraints.RELATIVE;
gbc.gridy=1;
contentPane.add(display,gbc);
gbc.gridx=GridBagConstraints.RELATIVE;
gbc.gridy=2;
contentPane.add(welcomeword,gbc);
dialogContentPane.setLayout(new GridBagLayout());
GridBagConstraints gbb=new GridBagConstraints();gbb.gridx=1;
gbb.gridy=0;
dialogContentPane.add(title,gbb);
gbb.gridx=GridBagConstraints.RELATIVE;
gbb.gridy=1;
dialogContentPane.add(name,gbb);
dialogContentPane.add(inputname,gbb);gbb.gridx=GridBagConstraints.RELATIVE;
gbb.gridy=2;
dialogContentPane.add(password,gbb);
dialogContentPane.add(inputpassword,gbb);
inputpassword.setEchoChar('*'); gbb.gridx=GridBagConstraints.RELATIVE;
gbb.gridy=3;
p.setLayout(new FlowLayout());p.add(ok);
p.add(cancel);gbb.gridx=1;
gbb.gridy=4;dialogContentPane.add(p,gbb);
display.addActionListener(this);
ok.addActionListener(this);
cancel.addActionListener(this);
}public void actionPerformed(ActionEvent e)
{
if(e.getSource()==display){
dialog.setBounds(200,200,300,200);
dialog.show();
}else if(e.getSource()==ok){
welcomeword.setText("您好,"+inputname.getText()+",欢迎光临中文Java技术网!");
}else if(e.getSource()==cancel){
welcomeword.setText("你没有输入!");
}
dialog.setVisible(false);
}
}

调试易

在applet中如何弹出对话框

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