Hello,

i would like to resize a JComboBox in order to fit its content. The way i thought to use is to get the component of all the item and use getPreferredSize():

   public static void redimensionnementAuto(JComboBox combo) {
       int width = 1, height = 1;
       
       JList jList = new JList();
       for (int i = 0; i < combo.getItemCount(); i++) {
           Object o = combo.getItemAt(i);
           
           ListCellRenderer lcr = combo.getRenderer();
           Component c = lcr.getListCellRendererComponent(jList, o, i,
                   combo.getSelectedIndex() == i, combo.hasFocus());
           
           Dimension dim = c.getPreferredSize();
           
           width = Math.max(dim.width, width);
           height = Math.max(dim.height, height);
       }
       
       // bordure
       width += 20;
       height += 5;
       
       combo.setSize(width, height);
   }

passing null as the JList cause a NPE at javax.swing.DefaultListCellRenderer.getListCellRendererComponent(DefaultListCellRenderer.java:80)

i'm not really happy with this way of doing. Is there any better way to achieve the same result?