Re: Java Euro Converter

From:

"R.Demandt" <r.demandt@gmail.com>

Newsgroups:

comp.lang.java.programmer

Date:

Sat, 06 Oct 2007 09:18:01 -0000

Message-ID:

<1191662281.098232.300990@19g2000hsx.googlegroups.com>

Hi,

This is what I have so far:

//Applet 01 - Euro Converter - Build_001

import java.applet.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

public class Euro extends Applet
{
   TextField invoer;
   TextField koers;

   Button eurogulden;
   Button guldeneuro;

   Label uitvoer;

   public void paint (Graphics pen)
   {
      invoer.setBounds(100,30,100,25);
      koers.setBounds(250,30,100,25);

      eurogulden.setBounds(125,100,100,25);
      guldeneuro.setBounds(225,100,100,25);

      uitvoer.setBounds(150,150,100,25);

      pen.drawString("Invoer:",100,20);
      pen.drawString("Koers:",250,20);
      pen.setColor(Color.black);
   }

   public void init()
   {
      guldeneuro.addActionListener(this);
      eurogulden.addActionListener(this);

      uitvoer=new Label("");
      add(uitvoer);

      invoer=new TextField("");
      add(invoer);

      koers=new TextField("2.20371");
      add(koers);

      eurogulden=new Button("Euro > Gulden");
      add(eurogulden);

      guldeneuro=new Button("Gulden > Euro");
      add(guldeneuro);
    }

   public void actionPerformed(ActionEvent actionevent)
   {
      actionevent.getSource();
           String s = actionevent.getActionCommand();

            if(s.equals("Euro > Gulden"))
            {
                if(invoer.getText() != "")
                {
                    Double double1 = new Double(invoer.getText());
                    double d = double1.doubleValue() /
koers.getText();
                    Double double3 = new Double(d);
                    uitvoer.setText(double3.toString());
                    return;
                }
            } else
            if(s.equals("Gulden > Euro") && invoer.getText() != "")
            {
                Double double2 = new Double(invoer.getText());
                double d1 = double2.doubleValue() * koers.getText();
                Double double4 = new Double(d1);
                uitvoer.setText(double4.toString());
            }
   }

}

But when compiling I get the following error's:
C:\Program Files\Java\Java Development Kit\bin\Euro.java:35:
addActionListener(java.awt.event.ActionListener) in java.awt.Button
cannot be applied to (Euro)
guldeneuro.addActionListener(this);
^
C:\Program Files\Java\Java Development Kit\bin\Euro.java:36:
addActionListener(java.awt.event.ActionListener) in java.awt.Button
cannot be applied to (Euro)
eurogulden.addActionListener(this);
^
C:\Program Files\Java\Java Development Kit\bin\Euro.java:64:
operator / cannot be applied to double,java.lang.String
double d = double1.doubleValue() / koers.getText();
^
C:\Program Files\Java\Java Development Kit\bin\Euro.java:70: cannot
find symbol
symbol : variable Invoer
location: class Euro
if(s.equals("Gulden > Euro") && Invoer.getText() != "")
^
C:\Program Files\Java\Java Development Kit\bin\Euro.java:73: operator
* cannot be applied to double,java.lang.String
double d1 = double2.doubleValue() * koers.getText();
^
5 errors

If anyone knows what I have to change, please let me know!

Thanks for any response,
R.Demandt