经常听朋友说，java编写的程序界面比较单一，不好进行个性化配置。现在让我们一起来了解有关Java界面样式相关类的知识，以及如何用Java写出变幻莫测的用户界面，让Java程序也拥有时髦的换肤功能。 实现原理 Java平台成熟后，设计人员与开发人员就熟悉到需要连续性好、兼容性好、轻易使用的Java程序界面。这时Sun就推出了“Look and Feel”机制迎合这种需求。它提供了一种独特的、与平台无关的程序外观，以及标准的界面行为。它可以在各个平台上使用同一“Look and Feel”，从而缩短设计与开发周期，降低软件使用人员的培训费用。这是“Look and Feel”设计的初衷。现在我们来使用这种特性为Java程序穿上花衣。
从JDK1.1.3开始，Sun提供了三个LookAndFeel的子类 javax.swing.plaf.metal.MetalLookAndFeel、com.sun.java.swing.plaf.motif.MotifLookAndFeel、com.sun.java.swing.plaf.windows. WindowsLookAndFeel。它们分别提供了“Metal”、“Motif”与“Windows”的界面式样。也就是说，任何基于Swing的界面程序本身都可以使用三种系统提供的皮肤。实际上我们也可以直接或间接继续LookAndFeel类，自己编写一种“皮肤”。在这里我们要使用到一个开放源代码的产品SKIN Look And Feel 1.2.2，在http://www.l2fPRod.com/可以找到它的全部源代码。Skin Look And Feel本身还可以更换http://www.l2fprod.com/提供的各种“皮肤”，让你的程序可以各种“皮肤”示人。
UIManager类
这个类就是Swing界面治理的核心，治理Swing的小应用程序以及应用程序样式的状态。UIManager类提供了下列静态方法用于更换与治理“Look and Feel”:
static void addAuxiliaryLookAndFeel(LookAndFeel laf) //增加一个“Look And Feel”到辅助的“look and feels”列表 static LookAndFeel[] getAuxiliaryLookAndFeels() //返回辅助的“look and feels”列表（可能为空）。 static String getCrossPlatformLookAndFeelClassName() //返回缺省的实现了跨平台的Look and Feel——即Java Look and Feel（JLF）。 static UIManager.LookAndFeelInfo[] getInstalledLookAndFeels() //返回了在目前已经安装的LookAndFeel的信息。 static LookAndFeel getLookAndFeel() //返回当前使用的Look and Feel static String getSystemLookAndFeelClassName() //返回与当前系统相关的本地系统Look and Feel，假如没有实现本地Look and Feel则返回缺省的跨平台的Look and Feel。 static void installLookAndFeel(String name, String className) //创建一个新的Look and Feel并安装到当前系统。 static void installLookAndFeel(UIManager.LookAndFeelInfo info) //创建一个新的Look and Feel并安装到当前系统。 static boolean removeAuxiliaryLookAndFeel(LookAndFeel laf) //从辅助的“look and feels”列表删除一个“Look And Feel” static void setInstalledLookAndFeels(UIManager.LookAndFeelInfo[] infos) //设置当前的已安装Look and Feel信。 static void setLookAndFeel(LookAndFeel newLookAndFeel) //设置当前使用的LookAndFeel。 static void setLookAndFeel(String className) //设置当前使用的LookAndFeel。参数是类名。
下面的源代码可以在Skin Look And Feel 1.2.2下的源代码根目录下找到（比如我下载的zip包是skinlf-1.2.2-20020611.zip，解压后，在src目录下的Skinit.java）。
public class Skinit extends javax.swing.JApplet { /** * The main program for the Skinit class * * @param args The command line arguments * @exception Exception Description of Exception */ public static void main(String[] args) throws Exception { if (args.length == 0) { printUsage(); } int mainClassNameIndex = -1; String gtktheme = null; String kdetheme = null; String packtheme = null;
for (int i = 0, c = args.length; i < c; i++) { if (args[i].equals("-gtk")) { gtktheme = args[++i]; } else if (args[i].equals("-kde")) { kdetheme = args[++i]; } else if (args[i].equals("-pack")) { packtheme = args[++i]; } else { mainClassNameIndex = i; break; } }
String[] realArgs = new String[args.length - mainClassNameIndex - 1]; for (int i = 0, c = realArgs.length; i < c; i++) { realArgs[i] = args[mainClassNameIndex + i + 1]; }
// First try to find the class Class clazz = null; try { clazz = Class.forName(args[mainClassNameIndex]); } catch (ClassNotFoundException e) { System.err.println("The class " + args[mainClassNameIndex] + " was not found in the classpath."); System.exit(1); } catch (Throwable e) { e.printStackTrace(); System.exit(1); } // if the class exists, get the main method Method mainMethod = null; try { mainMethod = clazz.getMethod("main", new Class[]{String[].class}); } catch (NoSUChMethodException e) { System.err.println("No method public static void main(String[] args) in " + clazz.getName()); System.exit(1); } catch (Throwable e) { e.printStackTrace(); System.exit(1); } // try to make sure the main method is accessible try { mainMethod.setAccessible(true); } catch (Throwable e) { } // main class and main method found, time to load the skin Skin skin = null; if (packtheme != null) { if (SkinUtils.DEBUG) { System.out.println("Loading themepack " + packtheme); } skin = SkinLookAndFeel.loadThemePack(packtheme); } else if (gtktheme != null) { if (kdetheme != null) { skin = new CompoundSkin(SkinLookAndFeel.loadSkin(gtktheme), SkinLookAndFeel.loadSkin(kdetheme)); } else { skin = SkinLookAndFeel.loadSkin(gtktheme); } } /* * try to use the user default skin */ if (skin == null) { if (SkinUtils.DEBUG) { System.out.println("Trying user skin"); } skin = SkinLookAndFeel.getSkin(); } if (skin != null) { SkinLookAndFeel.setSkin(skin); SkinLookAndFeel lnf = new SkinLookAndFeel(); UIManager.setLookAndFeel(lnf); UIManager.addPropertyChangeListener( new PropertyChangeListener() { public void propertyChange(PropertyChangeEvent event) { Object newLF = event.getNewValue(); if ((newLF instanceof SkinLookAndFeel) == false) { try { UIManager.setLookAndFeel(new SkinLookAndFeel()); } catch (Exception e) { e.printStackTrace(); } } } }); } else { System.out.println("No GTK theme provided, defaulting to application Look And Feel"); } try { mainMethod.invoke(null, new Object[]{realArgs}); } catch (IllegalAccessException e) { System.err.println("Please make sure the class " + clazz.getName() + " and the method main(String[] args) are public."); System.exit(1); } catch (Throwable e) { e.printStackTrace(); System.exit(1); } } /** * Description of the Method */ static void printUsage() { String usage = "Skinit - Skin Look And Feel wrapper/n" + "Usage: skinit [options] class [args...]/n" + "
