How to make a JComboBox table editor have the design of an ordinary JComboBox?
Solution 1:
Working from this complete example as a common frame of reference, note how the appearance of unselected cells in the ITEM_COL
column is due to the default renderer. The arrow button typical of a stand-alone JComboBox
only appears when the cell's editor is evoked, as by clicking on the cell or pressing Space when the cell is selected. You can add a triangle in a custom renderer:
final JComboBox combo = new JComboBox(items);
TableColumn col = table.getColumnModel().getColumn(ITEM_COL);
col.setCellRenderer(new DefaultTableCellRenderer(){
@Override
public Component getTableCellRendererComponent(JTable table, Object value,
boolean isSelected, boolean hasFocus, int row, int column) {
JLabel label = (JLabel) super.getTableCellRendererComponent(table,
value, isSelected, hasFocus, row, column);
label.setIcon(UIManager.getIcon("Table.descendingSortIcon"));
return label;
}
});
Addendum: A more complete example due to @aterai is seen here.
Solution 2:
In the spirit of moving forward I was going to post the solution that I was talking about earlier. This solution actually uses comboBox as a renderer. So it will look the same as a real comboBox in any LAF. The problem is that the text is squished, so I like trashgod's implementation better.
import java.awt.*;
import java.awt.event.*;
import java.util.List;
import java.util.ArrayList;
import javax.swing.*;
import javax.swing.border.*;
import javax.swing.table.*;
public class TableComboBoxByRow extends JFrame
{
List<TableCellEditor> editors = new ArrayList<TableCellEditor>(3);
public TableComboBoxByRow()
{
// Create the editors to be used for each row
String[] items1 = { "Red", "Blue", "Green" };
JComboBox comboBox1 = new JComboBox( items1 );
DefaultCellEditor dce1 = new DefaultCellEditor( comboBox1 );
editors.add( dce1 );
String[] items2 = { "Circle", "Square", "Triangle" };
JComboBox comboBox2 = new JComboBox( items2 );
DefaultCellEditor dce2 = new DefaultCellEditor( comboBox2 );
editors.add( dce2 );
String[] items3 = { "Apple", "Orange", "Banana" };
JComboBox comboBox3 = new JComboBox( items3 );
DefaultCellEditor dce3 = new DefaultCellEditor( comboBox3 );
editors.add( dce3 );
// Create the table with default data
Object[][] data =
{
{"Color", "Red"},
{"Shape", "Square"},
{"Fruit", "Banana"},
{"Plain", "Text"}
};
String[] columnNames = {"Type","Value"};
DefaultTableModel model = new DefaultTableModel(data, columnNames);
JTable table = new JTable(model)
{
// Determine editor to be used by row
public TableCellEditor getCellEditor(int row, int column)
{
int modelColumn = convertColumnIndexToModel( column );
if (modelColumn == 1 && row < 3)
return editors.get(row);
else
return super.getCellEditor(row, column);
}
};
JScrollPane scrollPane = new JScrollPane( table );
getContentPane().add( scrollPane );
table.getColumnModel().getColumn(1).setCellRenderer(new ComboBoxRenderer() );
}
class ComboBoxRenderer extends JComboBox implements TableCellRenderer
{
public ComboBoxRenderer()
{
setBorder(new EmptyBorder(0, 0, 0, 0));
}
public Component getTableCellRendererComponent(
JTable table, Object value, boolean isSelected,
boolean hasFocus, int row, int column)
{
// setFocusable(false);
removeAllItems();
addItem( value );
return this;
}
}
public static void main(String[] args)
{
TableComboBoxByRow frame = new TableComboBoxByRow();
frame.setDefaultCloseOperation( EXIT_ON_CLOSE );
frame.pack();
frame.setVisible(true);
}
}