Swing How to make dialogues

There are two types of dialog:

• modal
• non-modal: must use JDialog directly

Taken JFileChooser as Example:

1. Open a JFileChooser:

JFileChooserfileChooser = new JFileChooser();

2. Get value from it:

File file = fileChooser.getSelectedFile();

Code:

 import javax.swing.*;

 import java.awt.*;
 import java.awt.event.ActionEvent;
 import java.awt.event.ActionListener;
 import java.io.File;

 public class nameDlg extends JFrame {

 public nameDlg() {

 setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

 this.setTitle("GridBagLayout");

 this.setSize(600, 200);

 Container pane = this.getContentPane();

 GridBagLayout layout = new GridBagLayout();

 pane.setLayout(layout);

 GridBagConstraints c = new GridBagConstraints();

 // lable
 c.fill = GridBagConstraints.HORIZONTAL;
 c.gridx = 0;
 c.gridy = 0;
 c.insets = new Insets(3, 3, 3, 3);
 c.weightx = 0;
 c.weighty = 0.25;

 pane.add(new JLabel("Please enter the prefix:"), c);

 // textfield
 c.fill = GridBagConstraints.HORIZONTAL;
 c.gridx = 1;
 c.gridy = 0;
 c.gridwidth = 3;
 c.weightx = 0;

 pane.add(new JTextField(), c);

 // lable
 c.fill = GridBagConstraints.HORIZONTAL;
 c.gridx = 0;
 c.gridy = 1;
 c.gridwidth = 1;

 pane.add(new JLabel("Please enter the starting number:"), c);

 // textfield
 c.fill = GridBagConstraints.HORIZONTAL;
 c.gridx = 1;
 c.gridy = 1;
 c.gridwidth = 3;

 pane.add(new JTextField(), c);

 // lable
 c.fill = GridBagConstraints.HORIZONTAL;
 c.gridx = 0;
 c.gridy = 2;
 c.gridwidth = 1;

 pane.add(new JLabel("Please select a folder:"), c);

 // textfield shows file path
 c.fill = GridBagConstraints.HORIZONTAL;
 c.gridx = 1;
 c.gridy = 2;
 c.weightx = 0.75;

 final JTextField pathText = new JTextField();
 pane.add(pathText, c);

 // button
 c.fill = GridBagConstraints.HORIZONTAL;
 c.gridx = 2;
 c.gridy = 2;
 c.weightx = 0.25;

 JButton folderBtn = new JButton("Folder");

 folderBtn.addActionListener(new ActionListener() {
 JFileChooser fileChooser;

 @Override
 public void actionPerformed(ActionEvent event) {

 fileChooser = new JFileChooser();
 int returnVal = fileChooser.showOpenDialog(nameDlg.this);

 if (returnVal == JFileChooser.APPROVE_OPTION) {
 File file = fileChooser.getSelectedFile();

 pathText.setText(file.getPath());
 }

 }
 });

 pane.add(folderBtn, c);

 // button enter
 c.fill = GridBagConstraints.NONE;
 c.gridx = 0;
 c.gridy = 5;
 c.insets.top = 10;
 c.weightx = 0;

 pane.add(new JButton("Enter"), c);

 // button quit
 c.fill = GridBagConstraints.NONE;
 c.gridx = 1;
 c.gridy = 5;

 pane.add(new JButton("Quit"), c);

 this.setVisible(true);

 }
 }