display a non-selectable default value for JComboBox

Question

I have a JComboBox that contains three Items {\"Personel\", \"Magasinier\", \"Fournisseur\"}.

I want this JComboBox to display

Answer 1

The easiest and fastest way in my opinion is to use a customized ListCellRenderer

public class TestComboBox extends JComboBox {

  public TestComboBox() {
    super();
    setRenderer(new ItemRenderer());
  }

  public TestComboBox(ComboBoxModel aModel) {
    super(aModel);
    setRenderer(new ItemRenderer());
  }

  public TestComboBox(T[] items) {
    super(items);
    setRenderer(new ItemRenderer());
  }

  public TestComboBox(Vector items) {
    super(items);
    setRenderer(new ItemRenderer());
  }

  class ItemRenderer extends DefaultListCellRenderer {

    public Component getListCellRendererComponent(JList list, Object value, int index, boolean isSelected, boolean cellHasFocus){
        super.getListCellRendererComponent(list, value, index, isSelected, cellHasFocus);

        if (getSelectedItem() == null && index < 0){
            setText("placeholder");
        }
        return this;
    }
  }
}