JDialog not showing panel after closing and reopening

Question

The JDialog isn't showing the JPanel after closing of the dialog and then if the user immediately repeats the action it isn't showing a panel at all but a dialog that is solid black with a small white box in the top left corner. I have tried creating a SSCCE but couldn't develop one. If I remove the window adapter in MainControl class it will just keep adding another panel to the dialog after closing and repeating the opening of the dialog. Below is the code of the SSCCE that I tried creating but it still behaves the same. The code below is the minimal amount needed to run the dialog.

public class CreateAndShowUI {
  public static void createUI() {
    JFrame frame = new JFrame();
    MainPanel mainPanel = new MainPanel();
    Dialog dialog = new Dialog();
    MainControl mainControl = new MainControl(frame, mainPanel,
            dialog);

    frame.getContentPane().add(mainPanel.getMainPanel());
    frame.setUndecorated(true);
    frame.setPreferredSize(new Dimension(1100, 550));
    frame.pack();
    frame.setLocationRelativeTo(null);
    frame.setVisible(true);

  }
  public static void main(String[] args) {
    createUI();
  }
}


public class MainControl {
    private JFrame frame;
    private MainPanel mainPanel;
    private Dialog dialog;

    public MainControl(JFrame frame, MainPanel panel, Dialog dialog) {
        this.frame = frame;
        this.mainPanel = panel;
        this.dialog = dialog;
        mainPanel.getTable().addMouseListener(new MouseListener());
        dialog.getDialog().addWindowListener(new DialogWindowListener());
    }

    public class MouseListener extends MouseAdapter {
        @Override
        public void mousePressed(MouseEvent evt) {
            if (evt.getButton() == MouseEvent.BUTTON3) {
                dialog.showDialog(new KeywordPanel().getKeywordPanel(),
                        evt.getXOnScreen(), evt.getYOnScreen());
            }
        }
    }

    public class DialogWindowListener extends WindowAdapter {
        @Override
        public void windowClosing(final WindowEvent event) {
            dialog.getDialog().dispose();
            dialog.getDialog().removeAll();
        }
    }
}


public class MainPanel {
    private JPanel mainPanel;
    private JScrollPane listScrollPane;
    private JTable table;

    public MainPanel() {
        mainPanel = new JPanel(new MigLayout("", "", "[]13[]"));
        table = new JTable(new ProductTableModel());
        listScrollPane = new JScrollPane(table,
                JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED,
                JScrollPane.HORIZONTAL_SCROLLBAR_NEVER);
        listScrollPane.setPreferredSize(new Dimension(850, 990));
        mainPanel.add(listScrollPane, "cell 0 1");
    }

    public JPanel getMainPanel() {
        return mainPanel;
    }

    public JTable getTable() {
        return table;
    }
}


public class KeywordPanel {
  private JPanel keywordPanel;
  private JLabel searchLbl;

  public KeywordPanel() {
    searchLbl = new JLabel("KeyWords");
    keywordPanel = new JPanel();
    keywordPanel.add(searchLbl);
  }

  public JPanel getKeywordPanel() {
    return keywordPanel;
  }

}


public class Dialog {
    private JDialog dialog = new JDialog();

    public Dialog() {
        dialog.setLayout(new MigLayout());
    }

    public void showDialog(JPanel panel, int x, int y) {
        dialog.add(panel);
        dialog.pack();
        dialog.setVisible(true);
    }

    public JDialog getDialog() {
        return dialog;
    }

}


public class ProductTableModel extends AbstractTableModel {
  private ArrayList<Object> list = new ArrayList<Object>();
  private String[] columnNames = { "ID", "Description", "Inventory",
        "Minimum Quantity", "Cost", "Order Quantity" };

  public ProductTableModel() {
    list.add(new Product("Sup", "Sup", "Sup", 10, 20, "null"));
  }

  @Override
  public int getColumnCount() {
    return columnNames.length;
  }

  @Override
  public String getColumnName(int column) {
    switch (column) {
    case 0:
        return "<html>ID<br></html>";
    case 1:
        return "<html>Description<br></html>";
    case 2:
        return "<html>Inventory<br></html>";
    case 3:
        return "<html>Minimum<br>Quantity</html>";
    case 4:
        return "<html>Cost<br></html>";
    case 5:
        return "<html>Order<br>Quantity</html>";
    default:
        return null;
    }
  }

  @Override
  public int getRowCount() {
    return list.size();
  }

  @Override
  public boolean isCellEditable(int row, int column) {
    return true;
  }

  @Override
  public Object getValueAt(int row, int column) {

    if (list.get(row) instanceof Product) {

        Product product = (Product) list.get(row);
        switch (column) {
        case 0:
            return product.getId();
        case 1:
            return product.getProductDescription();
        case 2:
            return product.getQtyOnHand();
        case 3:
            return product.getMinQty();
        case 4:
            return product.getCost();
        case 5:
            return product.getOrderQty();
        default:
            throw new IndexOutOfBoundsException();
        }

    } else {
        return null;
    }
  }
}



public class Product {
  private int minQty;
  private double cost;
  private String productDescription, id, category, qtyOnHand, orderQty;

  public Product(String id, String productDescription, String qtyOnHand,
        int minQty, double cost, String orderQty) {

    this.setQtyOnHand(qtyOnHand);
    this.setOrderQty(orderQty);
    this.setId(id);
    this.setMinQty(minQty);
    this.setCost(cost);
    this.setProductDescription(productDescription);
  }

  public String getQtyOnHand() {
    return qtyOnHand;
  }

  public void setQtyOnHand(String qtyOnHand) {
    this.qtyOnHand = qtyOnHand;
  }

  public String getOrderQty() {
    return orderQty;
  }

  public void setOrderQty(String orderQty) {
    this.orderQty = orderQty;
  }

  public String getId() {
    return id;
  }

  public void setId(String id) {
    this.id = id;
  }

  public double getCost() {
    return cost;
  }

  public void setCost(double cost) {
    this.cost = cost;
  }

  public String getProductDescription() {
    return productDescription;
  }

  public void setProductDescription(String productDescription) {
    this.productDescription = productDescription;
  }

  public int getMinQty() {
    return minQty;
  }

  public void setMinQty(int minQty) {
    this.minQty = minQty;
  }

  public String getCategory() {
    return category;
  }

  public void setCategory(String category) {
    this.category = category;
  }
}

Answer 1

You should use

dialog.getContentPane().add(panel);

and

dialog.getDialog().getContentPane().removeAll();

And you also must NOT dispose the dialog,