Swing/ListCellAnimation のバックアップ(No.15)

class AnimeListCellRenderer extends JPanel implements ListCellRenderer {
  private static final Color selectedColor = new Color(230, 230, 255);
  private final AnimeIcon icon = new AnimeIcon();
  private final MarqueeLabel label = new MarqueeLabel();
  private final javax.swing.Timer animator;
  private final JList list;
  private boolean isRunning = false;
  int animate_index = -1;

  public AnimeListCellRenderer(final JList l) {
    super(new BorderLayout());
    this.list = l;
    animator = new Timer(80, new ActionListener() {
      @Override public void actionPerformed(ActionEvent e) {
        int i = l.getSelectedIndex();
        if (isRunning = (i >= 0)) {
          l.repaint(l.getCellBounds(i, i));
        }
      }
    });
    setOpaque(true);
    add(icon,  BorderLayout.WEST);
    add(label);
    animator.start();
  }

  @Override public Component getListCellRendererComponent(JList list, Object object,
      int index, boolean isSelected, boolean cellHasFocus) {
    setBackground(isSelected ? selectedColor : list.getBackground());
    label.setText((object == null) ? "" : object.toString());
    animate_index = index;
    return this;
  }

  private boolean isAnimatingCell() {
    return isRunning && animate_index == list.getSelectedIndex();
  }

  private class MarqueeLabel extends JLabel {
    // ...
  }
  // ...
}