Re: Controlling the scroll pane in JComboBox

Good suggestion, Pete! The code is below.

I welcome comments about all aspects of my code, but for now I'm
mostly interested in why there are no scroll bars when there is a
query and a panel is used for rendering...

Many thanks in advance,

Aaron

package pmg;

import java.awt.*;

import javax.swing.*;
import javax.swing.event.*;

import java.awt.event.*;
import java.util.ArrayList;

public class ChoiceGui extends JComboBox {
  private ArrayList<String> myList = new ArrayList<String>();
  private boolean mySettingItem = false;
  private boolean myRespondingToChangedQuery = false;

  public static void main(String[] args) {

    ArrayList<String> choices = new ArrayList<String>();
    choices.addAll(java.util.Arrays.asList(
        "Hello;Hello, World!;A very looooooooooooooong String;Very
Slow;Bad dog, bad!".split(";")));

    JFrame frame = new JFrame("Choice");
    frame.getContentPane().add(new ChoiceGui(choices));
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.pack();
    frame.setVisible(true);
  }

  public ChoiceGui(ArrayList<String> choices) {

    myList = choices;

    setEditor(new Editor());
    setRenderer(new Renderer3());
    setBackground(Color.getHSBColor(1f/6, .2f, 1f));

    this.setPreferredSize(new Dimension(150, 22));

    for (int s = 0; s < myList.size(); s++)
      this.addItem(myList.get(s));

    this.setSelectedIndex(-1);

    this.setEditable(true); // This is when the first setItem() is
called!
  }

  public class Editor implements ComboBoxEditor {
    private JTextField myTextField = new JTextField();

    public void addActionListener(ActionListener l)
{ myTextField.addActionListener(l); }
    public void removeActionListener(ActionListener l) { }
    public void setItem(Object item) {
      if (myRespondingToChangedQuery)
        return;

      System.out.println("setItem called!!!");
      mySettingItem = true;
      if (item != null) {
        myTextField.setText(item.toString());
        myTextField.setCaretPosition(0);
      }
      else if (!myRespondingToChangedQuery) // The value of
SuperChoice changed for a different reason, so the query must be
reset.
        myTextField.setText("");

      mySettingItem = false;
    }
    public void selectAll() { myTextField.selectAll(); }
    public Object getItem() { return null; }
    public Component getEditorComponent() { return myTextField; }

    public Editor() {
      myTextField.getDocument().addDocumentListener(new
DocumentListener() {
        public void dodo() {

          javax.swing.SwingUtilities.invokeLater(new Runnable() {
            public void run() {
              myRespondingToChangedQuery = true;

              String q =
((JTextField)getEditor().getEditorComponent()).getText();
              removeAllItems();
              for (int i = 0; i < myList.size(); i++)
                if
(myList.get(i).toUpperCase().contains(q.toUpperCase()))
                  addItem(myList.get(i));

              setPopupVisible(true);

              myRespondingToChangedQuery = false;

            }
          });
        }

        public void changedUpdate(DocumentEvent e) {
          if (mySettingItem)
            return;
          dodo();
        }
        public void insertUpdate(DocumentEvent e) {
          if (mySettingItem)
            return;
          dodo();
        }
        public void removeUpdate(DocumentEvent e) {
          if (mySettingItem)
            return;

          dodo();
        }
      });

    }
  }
  class Renderer3 implements ListCellRenderer {
    JPanel panel = new JPanel();
    JLabel label = new JLabel();
    JLabel label1 = new JLabel();
    JLabel label2 = new JLabel();
    JLabel label3 = new JLabel();

    public Renderer3() {
      panel.setLayout(new BoxLayout(panel, BoxLayout.X_AXIS));

      panel.add(label1);
      panel.add(label2);
      panel.add(label3);

      panel.setOpaque(true);
      panel.setBackground(Color.RED);
      Font font = label1.getFont();
      label.setFont(new Font(font.getName(), Font.PLAIN,
font.getSize()-2));
      label1.setFont(new Font(font.getName(), Font.PLAIN,
font.getSize()));
      label2.setFont(new Font(font.getName(), Font.BOLD,
font.getSize()));
      label3.setFont(new Font(font.getName(), Font.PLAIN,
font.getSize()));

      label.setOpaque(true);
      panel.setBackground(Color.getHSBColor(1f/6, .2f, 1f));
    }

    public Component getListCellRendererComponent(JList list, Object
value, int index, boolean isSelected, boolean cellHasFocus) {
      String str = (value!=null)?value.toString():"null";
      String q =
((JTextField)getEditor().getEditorComponent()).getText();
      if (q.length() != 0 &&
str.toUpperCase().indexOf(q.toUpperCase()) != -1) {
        int start = str.toUpperCase().indexOf(q.toUpperCase());
        label1.setText(str.substring(0, start));
        label2.setText(str.substring(start, start + q.length()));
        label3.setText(str.substring(start + q.length()));
        panel.setBackground(isSelected?
list.getSelectionBackground():list.getBackground());
        panel.setForeground(isSelected?
list.getSelectionForeground():list.getForeground());

        return panel;
      }
      else {
        Font font = label.getFont();
        label.setFont(new Font("Dialog", Font.PLAIN, 12));
        label.setBackground(isSelected?
list.getSelectionBackground():list.getBackground());
        label.setForeground(isSelected?
list.getSelectionForeground():list.getForeground());
        label.setText(" " + str);
        return label;
      }

    }
  }

}