webwork的开发团队opensymphony提供了一种优雅的解决页面布局的方法sitemesh。
sitemesh应用Decorator模式,用filter截取request和response,把页面组件head,content,banner
结合为一个完整的视图。通常我们都是用include标签在每个jsp页面中来不断的包含各种header, 
stylesheet, scripts and footer,现在,在sitemesh的帮助下,我们可以开心的删掉他们了
		下边是创建一个简单实例的步骤:
1,新建一个标准的web工程叫sitemesh
在WebRoot下新建一个index.jsp,内容如下
		
				1
				
						 <%
				@ page contentType
				=
				"
				text/html; charset=utf-8
				"
				%>
				
				<%
				@ page contentType
				=
				"
				text/html; charset=utf-8
				"
				%>
				
						
				
				2
				
						
								 this
				 is index.jsp.
						
				
				this
				 is index.jsp.
				3
				
						
								 it
				'
				s a simple page
						it
				'
				s a simple page 
		 
		接着在webRoot下新建几个目录
style2
login
shared
在login下建立目录style3
然後把index.jsp分别复制到style2,login/style3,shared下
现在访问下边的链接:
http://localhost:8080/sitemesh/index.jsp
http://localhost:8080/sitemesh/style2/index.jsp
http://localhost:8080/sitemesh/login/style3/index.jsp
http://localhost:8080/sitemesh/shared/index.jsp
得到的结果是一样的,那我们如何让这四个相同的index.jsp有不同的样式呢。除了每个里边加入include
还有个解决办法,就是sitemesh
2,在http://www.opensymphony.com下载sitemesh-2.2.1.jar,sitemesh-decorator.tld,sitemesh-page.tld
三个文件。
复制sitemesh.jar到WEB-INF/lib下,
复制sitemesh-decorator.tld,sitemesh-page.tld到WEB-INF下
把下边这部分加入web.xml
------------------------------------------------------------------------------
<filter>
  <filter-name>sitemesh</filter-name>
  <filter-class>com.opensymphony.module.sitemesh.filter.PageFilter</filter-class>
</filter>
		<filter-mapping>
  <filter-name>sitemesh</filter-name>
  <url-pattern>/*</url-pattern>
</filter-mapping>
		<taglib>
  <taglib-uri>sitemesh-decorator</taglib-uri>
  <taglib-location>/WEB-INF/sitemesh-decorator.tld</taglib-location>
</taglib>
		<taglib>
  <taglib-uri>sitemesh-page</taglib-uri>
  <taglib-location>/WEB-INF/sitemesh-page.tld</taglib-location>
</taglib>
--------------------------------------------------------------------------------
在WEB-INF下建立一个decorators.xml,内容如下
excludes代表不使用的部分
其它三个是匹配url,使用style
--------------------------------------------------------------------------
<decorators defaultdir="/decorators">
    <excludes>
        <pattern>/shared/*</pattern>    
    </excludes>
    <decorator name="style1" page="style1.jsp">
        <pattern>/*</pattern>
    </decorator>
    <decorator name="style2" page="style2.jsp">
        <pattern>/style2/*</pattern>
    </decorator>
    
    <decorator name="style3" page="style3.jsp">
        <pattern>/*/style3/*</pattern>
    </decorator>
</decorators>
--------------------------------------------------------------------------
在WebRoot下新建一个目录decorators
然後在下边建立三个jsp文件,内容如下
------------------------------------------------------------------
<%@ page contentType="text/html; charset=utf-8"%>
<%@ taglib uri="sitemesh-decorator" prefix="decorator" %>
<html>
  <head>
    <title><decorator:title default="装饰器页面..." /></title>
    <decorator:head />
  </head>
  <body>
    <p><font color="red">this is style2's header</font></p>
    <hr>
    <decorator:body />
    <hr>
    <p><font color="red">this is style1's footer</font></p>
  </body>
</html>
------------------------------------------------------------------
		<%@ page contentType="text/html; charset=utf-8"%>
<%@ taglib uri="sitemesh-decorator" prefix="decorator" %>
		<html>
  <head>
    <title><decorator:title default="装饰器页面..." /></title>
    <decorator:head />
  </head>
  <body>
    <p><font color="green">this is style2's header</font></p>
    <hr>
    <decorator:body />
    <hr>
    <p><font color="green">this is style2's footer</font></p>
  </body>
</html>
		------------------------------------------------------------------
<%@ page contentType="text/html; charset=utf-8"%>
<%@ taglib uri="sitemesh-decorator" prefix="decorator" %>
<html>
  <head>
    <title><decorator:title default="装饰器页面..." /></title>
    <decorator:head />
  </head>
  <body>
    <p><font color="blue">this is style3's header</font></p>
    <hr>
    <decorator:body />
    <hr>
    <p><font color="blue">this is style3's footer</font></p>
  </body>
</html>
------------------------------------------------------------------
再次访问
http://localhost:8080/sitemesh/index.jsphttp://localhost:8080/sitemesh/style2/index.jsphttp://localhost:8080/sitemesh/login/style3/index.jsphttp://localhost:8080/sitemesh/shared/index.jsp看到变化了吧。这只是个简单的展示,仔细思考一下你的需求,你能作出更好的布局方式。
sitemesh真不错。重要是学习简单20分种就搞定了
	
posted on 2006-12-14 20:12 
周锐 阅读(562) 
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