How to wait for a button press in Java

Question

I have a JFrame with some a JTextField and a JButton. I want it to behave like JOptionPane.showInputDialog(). Basically, I want to construct it, then call .start() or something which will make it visible and then wait for a button press and then return the contents of the JTextField. I have heard that wait()/notify() might do this, but I don't know if that's right for this and if it is, could I see a short example of how to use it?

That sounds like it might work. Can a JDialog contain more information than a JOptonPane (so it could replace a JFrame?) — Fractaly, Jun 20 '12 at 03:41
Actually they both have equal functionality, seems like you really don't know what `JOptionPane` can do, in real terms, other than showing the default Dialog windows to the user. You can manipulate `JOptionPane` to show what ever you need it to have. Here is one example regarding [JOptionPane usage](http://stackoverflow.com/questions/10306901/how-to-change-highlighting-color-in-java-swing-textarea-and-also-change-the-be/10309277#10309277), have a look at this too :-) — nIcE cOw, Jun 20 '12 at 04:02
Do watch the `JButton` (with name "HIGHLIGHT TEXT")'s `actionPerformed(...)` method, watch the second argument in this line `int selection = JOptionPane.showConfirmDialog(frame, getOptionPanel(), "Highlight Colour : ",JOptionPane.OK_CANCEL_OPTION, JOptionPane.PLAIN_MESSAGE);`, this can give you one idea, which means you can add your own `JPanel` and put whatever you want to put in that `JPanel` and use the same `JOptionPane` for your specific needs :-) — nIcE cOw, Jun 20 '12 at 04:07

score 3 · Answer 1 · answered Jun 20 '12 at 03:55

3

Also JDialog is your solution for custom input dialogs, there is library which can help speed up your development. It is called TaskDailog.

More info at http://code.google.com/p/oxbow/wiki/TaskDialogIntroduction?tm=6

answered Jun 20 '12 at 03:55

Eugene Ryzhikov

17,131
3
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score 3 · Accepted Answer · answered Jun 20 '12 at 03:59

Here try this code example using JDialog :

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

public class DialogExample extends JFrame
{
    private JLabel nameLabel;

    public DialogExample()
    {
        super("Dialog Example");
    }

    private void createAndDisplayGUI()
    {       
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        JPanel contentPane = new JPanel();
        nameLabel = new JLabel();
        contentPane.add(nameLabel);

        setContentPane(contentPane);
        setSize(200, 100);
        setLocationByPlatform(true);
        setVisible(true);

        MyDialog dialog = new MyDialog(this, "Credentials : ", true);
        dialog.createAndDisplayGUI();
    }

    public void setName(String name)
    {
        if (name.length() > 0)
            nameLabel.setText(name);
        else
            nameLabel.setText("Empty string received.");
    }


    public static void main(String... args)
    {
        SwingUtilities.invokeLater(new Runnable()
        {
            public void run()
            {
                new DialogExample().createAndDisplayGUI();
            }
        });
    }
}

class MyDialog extends JDialog
{
    private JTextField nameField;
    private JFrame frame;

    public MyDialog(JFrame f
            , String title, boolean isModal)
    {
        super(f, title, isModal);
        frame = f;
    }

    public void createAndDisplayGUI()
    {
        JPanel contentPane = new JPanel();
        contentPane.setLayout(new FlowLayout(FlowLayout.LEFT, 5, 5));
        JLabel nameLabel = new JLabel("Please Enter your Name : ");
        nameField = new JTextField(10);
        JButton submitButton = new JButton("SUBMIT");
        submitButton.addActionListener(new ActionListener()
        {
            public void actionPerformed(ActionEvent ae)
            {
                if (nameField.getDocument().getLength() > 0)
                    frame.setName(nameField.getText());
                else
                    frame.setName("");
                MyDialog.this.dispose();    
            }
        });

        contentPane.add(nameLabel);
        contentPane.add(nameField);
        contentPane.add(submitButton);

        add(contentPane);
        pack();
        setVisible(true);
    }
}

That was almost exactly the solution I was working on. You probably just saved me half an hour. Thanks — Fractaly, Jun 20 '12 at 04:09
You are MOST WELCOME and KEEP SMILING :-). HAPPY to know that my answer did helped you somewhere :-) — nIcE cOw, Jun 20 '12 at 04:10
One thing though- can I make it return its value like JOptionPane.showInputDialog, where it doesn't need to backcall on the frame? — Fractaly, Jun 20 '12 at 04:11
Yesh, true, just change the logic inside the `actionPerformed(...)` method of the `Submit JButton`, or else you can take the approach as shown in the comment by me, regarding using `JOptionPane` in the same manner as `JDialog` (in some sense) :-) — nIcE cOw, Jun 20 '12 at 04:13

How to wait for a button press in Java

2 Answers2