Error with Gridlayout in dialog

Question

Hello,
I wondered if anyone could advise, in this dialog code I was hoping the first panel to display the labels and textfields as 2 columns, with 3 rows. The second panel works fine, could anyone see the problem in the first?
Thank you
The first panel should be:
oneLb oneTf
twoLb twoTf
threeLb threeTf
fourLb fourTf
public class testDialog extends JDialog implements ActionListener{
JLabel oneLb, twoLb, threeLb, fourLb;
JTextField oneTf, twoTf, threeTf, fourTf;
JButton oneBt, twoBt;
BuildPanel(){
JPanel panel = new JPanel(new GridLayout(3,2,15,10));
panel.add(oneLb = new JLabel("One"));
panel.add(oneTf = new JTextField());
oneTf.addActionListener(this);
panel.add(twoLb = new JLabel("Two"));
panel.add(twoTf = new JTextField());
twoTf.addActionListener(this);
panel.add(threeLb = new JLabel("Three"));
panel.add(threeTf = new JTextField());
threeTf.addActionListener(this);
panel.add(fourLb = new JLabel("Four"));
panel.add(fourTf = new JTextField());
fourTf.addActionListener(this);
JPanel panel1 = new JPanel();
panel1.add(oneBt = new JButton("Button 1"));
panel1.add(twoBt = new JButton("Button 2"));
getContentPane().add(panel, BorderLayout.CENTER);
getContentPane().add(panel1, BorderLayout.SOUTH);
pack();
     setResizable(true);
public void actionPerformed(ActionEvent e){

Answer 1

I wondered if you could advise of any method to copy
the whole number entered in a textfield, to an int
var? I tried the functions getValue, and casting to
Integer, this did not appear to work.I'm not sure what you're doing: JTextField doesn't have a method getValue.
Two ways to get the contents out of a JTextField is to use its method getText,
or to use an ActionListener and the ActionEvent method getActionCommand:
JTextField field = new JTextField(10);
field.addActionListener(new ActionListener(){
    public void actionPerformed(ActionEvent evt) {
        String input = evt.getActionCommand();
});In either case, the result is a String. Casting never turns a String into anything else! You
need to use a method like Integer.parseInt.
Instead of a JTextField, you could also try JFormattedTextField. Here's an article.
You can also add an InputVerifier to any component.
My one beef with these, is that they are used when the component loses focus and doing common
things like pressing enter to trigger the default button doesn't cause a loss of focus :-(
>
Could I also ask, I have seen you offering much advise
on the 2d pages. And just wondered if you had ever
written a classical connected components algorithm in
java?It's been a long time since I wrote any graph algorithms, and then it wasn't in Java.