Problems with calling a ProgressBar dialog in another class

[Allgorythm]

hi, I dont know why does my progressBar dialog doesnt appear correctly as I want.
the frame does appear but the container is transparent, i cant see the progress bar ,i cant figure a way how to solve this problem.
how can i make a progressBar dialog outside my class that i can call with no problems like this? i tried to search at google but i cant understand most of it so i decide to post my question here.

public class TableSample extends JFrame {

    private JTextField searchField;
    private JTable table;
    private JPanel panel;
    private JScrollPane scroll;

    public TableSample() {


        panel = new JPanel();

        searchField = new JTextField();

        panel.setLayout(null);

        final String[] columns = {"Name", "Surname", "Age"};

        final Object[][] names = {{"Jhon", "Java", "23"}, {"Stupid", "Stupido", "500"},
                                {"Michael", "Winnie", "20"}, {"Winnie", "Thepoor", "23"},
                                {"Michael", "Winnie", "20"}, {"Winnie", "Thepoor", "23"},
                                {"Michael", "Winnie", "20"}, {"Winnie", "Thepoor", "23"},
                                {"Michael", "Winnie", "20"}, {"Winnie", "Thepoor", "23"},
                                {"Michael", "Winnie", "20"}, {"Winnie", "Thepoor", "23"},
                                {"Michael", "Winnie", "20"}, {"Winnie", "Thepoor", "23"},
                                {"Michael", "Winnie", "20"}, {"Winnie", "Thepoor", "23"},
                                {"Michael", "Winnie", "20"}, {"Winnie", "Thepoor", "23"},
                                {"Michael", "Winnie", "20"}, {"Winnie", "Thepoor", "23"}};

        table = new JTable(names, columns);
        table.setColumnSelectionAllowed(true);
        table.setRowSelectionAllowed(true);

        scroll = new JScrollPane(table);
        scroll.setBounds(0, 100, 900, 500);

        
        searchField.setBounds(10, 50, 150, 20);
        searchField.addActionListener(new ActionListener() {

            public void actionPerformed(ActionEvent e) {

                new ProgressBar();
                
                // set the column selection to false to gain multiple row selection
                table.setColumnSelectionAllowed(false);

                // clear the selection for the next search, so the table wont
                // be flooded by selection highlight.
                table.clearSelection();

                String value = searchField.getText();

                for (int row = 0; row <= table.getRowCount() - 1; row++) {

                    for (int col = 0; col <= table.getColumnCount() - 1; col++) {

                        if (value.equals(table.getValueAt(row, col))) {

                            // this will automatically set the view of the scroll in the location of the value
                            table.scrollRectToVisible(table.getCellRect(row, col, true));

                            // this will automatically set the focus of the searched/selected row/value
                            table.addRowSelectionInterval(row, row);

                            for (int i = 0; i <= table.getColumnCount() - 1; i++) {

                                //table.getColumnModel().getColumn(i).setCellRenderer(new SingleAndMultipleRowSelectionRenderer());
                            }
                        }
                    }
                }
            }
        });

        panel.add(searchField);
        panel.add(scroll);

        getContentPane().add(panel);

        setDefaultCloseOperation(EXIT_ON_CLOSE);
        setSize(906, 700);
        setLocationRelativeTo(null);
        setVisible(true);
    }

    public static void main(String[] args) {

        new TableSample();
    }
}

the progressbar

import java.awt.BorderLayout;

import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JProgressBar;

public class ProgressBar {


    JDialog dialog;
    JProgressBar progressBar;

    public ProgressBar() {

        dialog = new JDialog(new JFrame(), "Progress Dialog", true);

        progressBar = new JProgressBar(0, 500);
    
        dialog.add(BorderLayout.CENTER, progressBar);
        dialog.setSize(300, 75);
        dialog.setLocationRelativeTo(null);

        Thread t = new Thread(new Runnable() {

            public void run() {

                dialog.setVisible(true);
            }
        });
        t.start();

        for (int i = 0; i <= 500; i++) {

            progressBar.setValue(i);

            try {

                Thread.sleep(2);
            }
            catch (InterruptedException e) {

                e.printStackTrace();
            }
        }
  }
}

[r035198x]

How to Use Progress Bars (The Java™ Tutorials > Creating a GUI With JFC/Swing > Using Swing Components)