Change icon of JComboBox arrow button

Question

Thanks for reply

but this what i want to do:

When a key is pressed in an editable combobox, I want the popup menu of the jcombobox to appear automatically, and get the text written in it, but when I changed the icon of the arrow button,the icon changed but the popup menu doesn't appear when key is pressed.

When I tried to do this in Windows look and feel, it worked fine without any problems, but in Synth look and feel, it didn't work. I searched for two days but I couldn't solve the problem.

I tried to use document listener but nothing changed or i didnt use it correctly

I hope my problem is clarified this time

JTextField editor;
.
.
.
editor = (JTextField) jComboBox1.getEditor().getEditorComponent();

\\ 

editor.addKeyListener(new KeyAdapter() {
@Override
public void keyReleased(KeyEvent e) {

    if (jComboBox1.isDisplayable())
    {
        jComboBox1.setPopupVisible(true);
    }

         System.out.println(editor.getText());
}
});

\\ change arrowbutton icon

jComboBox1.setUI(new SynthComboBoxUI() {

   @Override
   protected JButton createArrowButton() {
      JButton btn = new JButton();
      btn.setIcon(new javax.swing.ImageIcon(getClass().getResource("/Image/error3.png")));
      return btn;
   }
});

Answer 1

1. don't use KeyListener , use DocumentFilter for filtering unwanted chars or DocumentListener

2. JTextComponents returns Document (derived JTextField or JFormattedTextField from JComboBox / JSpinner )

3. put Icon to the definitions saved into xml file for Synt , you can to test that by derive SynthButtonUI from JComboBOx

4. from Synth L&F to use Nimbus

5. use Custom Look and Feel , part of them override methods from BasicXxxUI directly