JComboBox

[John Brookes]

I have a few JComboBox instances in a GUI I've made. They all start off empty and get populated by the user, but because they start empty they look rubbish on the screen. I can't for the life of me find a way to set a default string to appear in an otherwise empty combo box. I just want to put in "-----" or something to set an initial size.

[Campbell Ritchie]

Have you tried setting them invisible (setVisible(false)) before they are populated??? Or maybe setPopupVisible()?

[John Brookes]

Ah good call. I'll give it a go but I'd rather have them in place with a default string to keep the layout more consistent.

[Michael Dunn]

    
import javax.swing.*;
import java.awt.*;
class Testing extends JFrame
{
  public Testing()
  {
    setLocation(400,300);
    setDefaultCloseOperation(EXIT_ON_CLOSE);
    JPanel jp = new JPanel();
    JComboBox cbo = new JComboBox();
    cbo.setPrototypeDisplayValue("123456789");//<---------any length string you want
    jp.add(cbo);
    getContentPane().add(jp);
    pack();
  }
  public static void main(String args[]){new Testing().setVisible(true);}
}