识别可以用作“橡皮图章”来绘制JList中的单元格的组件。
例如，使用一个JLabel作为ListCellRenderer，你会写是这样的：
class MyCellRenderer extends JLabel implements ListCellRenderer<Object> { public MyCellRenderer() { setOpaque(true); } public Component getListCellRendererComponent(JList<?> list, Object value, int index, boolean isSelected, boolean cellHasFocus) { setText(value.toString()); Color background; Color foreground; // check if this cell represents the current DnD drop location JList.DropLocation dropLocation = list.getDropLocation(); if (dropLocation != null && !dropLocation.isInsert() && dropLocation.getIndex() == index) { background = Color.BLUE; foreground = Color.WHITE; // check if this cell is selected } else if (isSelected) { background = Color.RED; foreground = Color.WHITE; // unselected, and not the DnD drop location } else { background = Color.WHITE; foreground = Color.BLACK; }; setBackground(background); setForeground(foreground); return this; } }