Question

I’ve made a custom TableCellRenderer that displays a JPanel. When the JPanel contains interactive elements I want those to work too, so I made a custom TableCellEditor. It works, but there is some weird behavior when clicking through the JPanels. Sometimes a JPanel disappears when clicked.
When I only set a custom renderer there are no problems at all, except for the JPanels not being interactive. So the problem must be in the TableCellEditor.

Editor:

public class PanelTableCellEditor
        extends AbstractCellEditor
        implements TableCellEditor
{
    private Object _component;

    @Override
    public Object getCellEditorValue()
    {
        return _component;
    }

    @Override
    public Component getTableCellEditorComponent(JTable table, Object value,
                                                 boolean isSelected, int row,
                                                 int column)
    {
        _component = value;
        if (value instanceof JPanel)
        {
            ((Component) value).setForeground(UIManager.getColor("List.selectionForeground"));
            ((Component) value).setBackground(UIManager.getColor("List.selectionBackground"));
            return ((Component) value);
        }
        else
        {
            return null;
        }
    }
}

Renderer:

public class PanelTableCellRenderer
        extends Component
        implements TableCellRenderer
{
    @Override
    public Component getTableCellRendererComponent(JTable table, Object value,
                                                   boolean isSelected,
                                                   boolean hasFocus, int row,
                                                   int column)
    {
        if (value instanceof JPanel)
        {
            if (isSelected || hasFocus)
            {
                ((Component) value).setForeground(UIManager.getColor("List.selectionForeground"));
                ((Component) value).setBackground(UIManager.getColor("List.selectionBackground"));
            }
            else
            {
                ((Component) value).setForeground(UIManager.getColor("Panel.foreground"));
                ((Component) value).setBackground(UIManager.getColor("Panel.background"));
            }

            return ((Component) value);
        }
        else
        {
            return new DefaultTableCellRenderer().getTableCellRendererComponent(table, value, isSelected, hasFocus, row, column);
        }
    }
}

In the main form I have the next code:

DefaultTableModel model = new DefaultTableModel();
        model.addColumn(null, new Object[]
                {
                    jPanel1, jPanel2, jPanel1, jPanel2, jPanel1, jPanel2, jPanel1, jPanel2, jPanel1, jPanel2, jPanel1
                });
        jTable1.setModel(model);
        TableColumn column = jTable1.getColumnModel().getColumn(0);
        column.setCellRenderer(new PanelTableCellRenderer());
        column.setCellEditor(new PanelTableCellEditor());
        jTable1.setRowHeight(50);
        jTable1.setTableHeader(null);
        jScrollPane2.setColumnHeaderView(null);

Answer 1

There are two issues that I see here :

*Duplicate placed AWT/SWING components are a no-no ! *

1) Adding the same component twice to a panel causes issues. Swing doesn’t like the same component to exist in different locations — the state of the gui, dedrawing, etc, is all based on a model of one component – one location. I’ve had similar problems to yours in the past, where a component went blank because it was being added multiple times…

Missing variables ?

2) The variables jPanel1/jPanel2 are not defined anywhere in your code. I assume that this is not a problem in your actual code, though — so maybe if you show those definitions, there could be other problems.