JPanel

heavy482

i need a good site for explaining how a ticketmachinepanal is created

my class is
public class TicketMachinePanel extends JPanel implements ActionListener

and i have to take information though the ticketmachine class that i have that is
used by the panel.

public TicketMachinePanel(TicketMachine machine)
{
this.machine = machine; //connect GUI to machine

setPreferredSize(new Dimension(250, 100));

getContentPane().add(machine);
getContentPane().add(input);
getContentPane().add(priceButton);
getContentPane().add(prompt);

display.setLineWrap(true);
display.setEditable(false);

priceButton.addActionListener(this);

input.addActionListener(this);

Afuera

Have you implemented the ActionListener interface in your TicketMachinePanel class?
(All it needs is an actionPerformed(ActionEvent e) method.)

The addActionListener() method calls, that you already have, register a class to listen on the actions of a component. In your case, you have registered the TicketMachinePanel (i.e. "this") class to listen to the "priceButton" and the "input" components.

When there is an action performed on these components the actionPerformed(ActionEvent e) method will get triggered. You will need to catch and parse each type of action, by reading the ActionEvent parameter that comes as part of the call. Check out the API docs for more details on what you can extract from the ActionEvent.

heavy482

can you help..
i need a
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

/**
*
*/
public class TicketMachinePanel extends JPanel implements ActionListener
{
private TicketMachine machine;
private JTextField input=new JTextField(6);
private JButton priceButton=new JButton("Button");
private JLabel inputmsg=new JLabel("");
private JLabel outputmsg=new JLabel("");

public TicketMachinePanel(TicketMachine machine)
{
this.machine = machine; //connect GUI to machine

setPreferredSize(new Dimension(250, 100));

getContentPane().add(machine);
getContentPane().add(input);
getContentPane().add(priceButton);
getContentPane().add(inputmsg);
getContentPane().add(outputmsg);
display.setLineWrap(true);
display.setEditable(false);

priceButton.addActionListener(this);

input.addActionListener(this);


}
public void actionPerformed(ActionEvent e)
{
if(e.getSource()==priceButton || e.getSource()==input)

{

System.out.print(inputmsg);

input.setText("");
}

}

public static void main(String args[])
{
ButtonGUI f=new ButtonGUI();
f.setSize(400,300);
f.setVisible(true);

f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);


}
}

Creamy Goodness

my java is fairly rusty but in your main method you aren't creating an instance of the TicketMachinePanel class.

where has this ButtonGUI come from?

heavy482

i have everything conpilling except the main class and im not sure why it cant reckonise it

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

/**
*
*/
public class TicketMachinePanel extends JPanel implements ActionListener
{
private TicketMachine machine;
private JTextField display;
private JButton priceButton;
private JLabel inputmsg;
private JLabel outputmsg;

public TicketMachinePanel(TicketMachine machine)
{
this.machine = machine; //connect GUI to machine

setPreferredSize(new Dimension(250, 100));

JPanel p = new JPanel(new FlowLayout(FlowLayout.LEFT));


this.add(new JTextField(""));
this.add(new JButton("Button"));
this.add(new JLabel(""));
this.add(new JLabel(""));


priceButton.addActionListener(this);

display.addActionListener(this);


}

public void actionPerformed(ActionEvent e)
{
if(e.getSource()==priceButton)
{
inputmsg.setText("dewjhdne");
outputmsg.setText("dewjhdne");

}

}
public static void main(String args[])
{
TicketMachinePanel p=new TicketMachinePanel();
p.setSize(400,300);
p.setVisible(true);

TicketMachinePanel.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);


}

}

Creamy Goodness

p.setSize(400,300);
p.setVisible(true);

TicketMachinePanel.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

these should be in a constructor of some kind.

also the setVisible() method has to be the last method called otherwise the way you have it now the setdefaulCloseOperation() will not act on the window.

heavy482

how come it works in this one

also i have JFrame at the EXIT_ON_CLOSE will this still work if its extending to JPanel

heavy482

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

public class ButtonGUI extends JFrame implements ActionListener
{

private JLabel prompt=new JLabel("Enter number to double:");
private JTextField input=new JTextField(6);
private JTextArea display= new JTextArea(10,20);
private JButton doubleButton=new JButton("Double it!");

public ButtonGUI()
{
setLayout(new FlowLayout());
getContentPane().add(prompt);
getContentPane().add(input);
getContentPane().add(doubleButton);
getContentPane().add(display);

display.setLineWrap(true);
display.setEditable(false);

doubleButton.addActionListener(this);

input.addActionListener(this);


}
public void actionPerformed(ActionEvent e)
{
if(e.getSource()==doubleButton || e.getSource()==input)

{
double value=Double.valueOf(input.getText()).doubleValue();
double valueDoubled=value*2;
display.append("Double of "+value+"is;"+valueDoubled+"\n");

input.setText("");
}

}

public static void main(String args[])
{
ButtonGUI f=new ButtonGUI();
f.setSize(400,300);
f.setVisible(true);

f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);


}
}

radioactiveman

basically because you extend JFrame in that code and set it to visible which is fine. If you extend JPanel, you'll have to add it to the jframe in main. It would be a call like f.add(this) - because 'this' is the JPanel. It's just a different approach.

heavy482

thanks all sorted