定义自己的JList渲染方式，可用于添加icon改变选中时的行为等

import java.awt.BorderLayout;import java.awt.Color;import java.awt.Component;import java.awt.Container;import java.awt.Dimension;import java.awt.Font;import java.awt.FontMetrics;import java.awt.Graphics;import java.util.ArrayList;import javax.swing.JComponent;import javax.swing.JFrame;import javax.swing.JList;import javax.swing.JPanel;import javax.swing.JScrollPane;import javax.swing.JTextArea;import javax.swing.ListCellRenderer;import javax.swing.ListSelectionModel;import javax.swing.event.ListSelectionEvent;import javax.swing.event.ListSelectionListener;public class JListRenderTest {public static void main(String[] args) {JFrame frame=new ListRenderFrame();frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);frame.setVisible(true);}}class ListRenderFrame extends JFrame{private JTextArea text;private JList fontList;public ListRenderFrame(){this.setTitle("JListRenderTest");//窗口大小this.setSize(400,300);//字体列表ArrayList<Font> fonts=new ArrayList<Font>();fonts.add(new Font("Cambria",Font.PLAIN,14));fonts.add(new Font("Aharoni",Font.PLAIN,14));fonts.add(new Font("Gungsuh",Font.PLAIN,14));fonts.add(new Font("Batang",Font.PLAIN,14));fonts.add(new Font("MingLiU_HKSCS",Font.PLAIN,14));fonts.add(new Font("Times New Roman",Font.PLAIN,14));//创建JListfontList=new JList(fonts.toArray());//设置JList的可见行数fontList.setVisibleRowCount(5);//设置JList的选择模式为单选fontList.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);//设置自定义的CellRenderfontList.setCellRenderer(new FontCellRender());//添加滚动条支持JScrollPane pane=new JScrollPane(fontList);JPanel p=new JPanel();p.add(pane);//添加事件处理this.fontList.addListSelectionListener(new ListSelectionListener(){public void valueChanged(ListSelectionEvent e) {Font font=(Font) fontList.getSelectedValue();text.setFont(font);}});Container contentPane=this.getContentPane();contentPane.add(p,BorderLayout.WEST);//创建JTextAreatext=new JTextArea("Please notice the font of thease words");//设置JTextArea字体text.setFont(fonts.get(0));//设置JTextArea自动换行text.setLineWrap(true);//设置JTextArea的换行方式，设置为true的时候最后一个单词会保持其完整性，整体下移一行，设置为false则最后一个单词超出的时候会截断text.setWrapStyleWord(false);contentPane.add(text,BorderLayout.CENTER);}}//实现自定义的CellRender，它对JList中的每一行的渲染做控制，可以用于添加Icon之类的复杂控制class FontCellRender extends JComponent implements ListCellRenderer{private Font font;private Color background;private Color foreground;//实现ListCellRenderer接口的方法public Component getListCellRendererComponent(JList list, Object value,int index, boolean isSelected, boolean cellHasFocus) {font =(Font) value;background=isSelected?list.getSelectionBackground():list.getBackground();foreground=isSelected?list.getSelectionForeground():list.getForeground();return this;}//实现每行的绘制@Overrideprotected void paintComponent(Graphics g) {String text=font.getFamily();FontMetrics fm=g.getFontMetrics(font);g.setColor(background);g.fillRect(0, 0, this.getWidth(), this.getHeight());g.setColor(foreground);g.setFont(font);g.drawString(text, 0, fm.getAscent());}//计算每行的宽度，在显示时会被调用@Overridepublic Dimension getPreferredSize() {String text=font.getFamily();Graphics g=this.getGraphics();FontMetrics fm=g.getFontMetrics(font);return new Dimension(fm.stringWidth(text),fm.getHeight());}}