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| <title>6.4. Navigation</title><link rel="stylesheet" href="css/stylesheet.css" type="text/css"><meta name="generator" content="DocBook XSL Stylesheets V1.75.0"><link rel="home" href="index.html" title="Apache Click"><link rel="up" href="ch06.html" title="Chapter 6. Best Practices"><link rel="prev" href="ch06s03.html" title="6.3. Page Auto Mapping"><link rel="next" href="ch06s05.html" title="6.5. Templating"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">6.4. Navigation</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="ch06s03.html">Prev</a> </td><th width="60%" align="center">Chapter 6. Best Practices</th><td width="20%" align="right"> <a accesskey="n" href="ch06s05.html">Next</a></td></tr></table><hr></div><div class="sect1" title="6.4. Navigation"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="navigation"></a>6.4. Navigation</h2></div></div></div><p> When navigating between Pages using forwards and redirects, you should |
| refer to the target page using the Page class rather than using path. This |
| provides you compile time checking and will save you from having to update |
| path strings in Java code if you move pages about. |
| </p><p>To forward to another page using the Page class: |
| </p><pre class="programlisting"><span xmlns:fo="http://www.w3.org/1999/XSL/Format" class="kwd">public</span> <span xmlns:fo="http://www.w3.org/1999/XSL/Format" class="kwd">class</span> CustomerListPage <span xmlns:fo="http://www.w3.org/1999/XSL/Format" class="kwd">extends</span> Page { |
| |
| <span xmlns:fo="http://www.w3.org/1999/XSL/Format" class="kwd">public</span> ActionLink customerLink = <span xmlns:fo="http://www.w3.org/1999/XSL/Format" class="kwd">new</span> ActionLink(<span xmlns:fo="http://www.w3.org/1999/XSL/Format" class="kwd">this</span>,<span xmlns:fo="http://www.w3.org/1999/XSL/Format" class="str">"onCustomerClick"</span>); |
| |
| .. |
| |
| <span xmlns:fo="http://www.w3.org/1999/XSL/Format" class="kwd">public</span> <span xmlns:fo="http://www.w3.org/1999/XSL/Format" class="kwd">boolean</span> onCustomerClick() { |
| Integer id = customerLink.getValueInteger(); |
| Customer customer = getCustomerService().getCustomer(id); |
| |
| CustomerDetailPage customerDetailPage = (CustomerDetailPage) |
| getContext().createPage(CustomerDetailPage.<span xmlns:fo="http://www.w3.org/1999/XSL/Format" class="kwd">class</span>); |
| |
| customerDetailPage.setCustomer(customer); |
| setForward(customerDetailPage); |
| |
| <span xmlns:fo="http://www.w3.org/1999/XSL/Format" class="kwd">return</span> false; |
| } |
| }</pre><p>To redirect to another page using the Page class you can obtain the pages |
| path from the <code class="classname">Context</code>. In the example below we are passing |
| through the customer id as a request parameter to the target page. |
| </p><pre class="programlisting"><span xmlns:fo="http://www.w3.org/1999/XSL/Format" class="kwd">public</span> <span xmlns:fo="http://www.w3.org/1999/XSL/Format" class="kwd">class</span> CustomerListPage <span xmlns:fo="http://www.w3.org/1999/XSL/Format" class="kwd">extends</span> Page { |
| |
| <span xmlns:fo="http://www.w3.org/1999/XSL/Format" class="kwd">public</span> ActionLink customerLink = <span xmlns:fo="http://www.w3.org/1999/XSL/Format" class="kwd">new</span> ActionLink(<span xmlns:fo="http://www.w3.org/1999/XSL/Format" class="kwd">this</span>, <span xmlns:fo="http://www.w3.org/1999/XSL/Format" class="str">"onCustomerClick"</span>); |
| |
| .. |
| |
| <span xmlns:fo="http://www.w3.org/1999/XSL/Format" class="kwd">public</span> <span xmlns:fo="http://www.w3.org/1999/XSL/Format" class="kwd">boolean</span> onCustomerClick() { |
| String id = customerLink.getValueInteger(); |
| |
| String path = getContext().getPagePath(CustomerDetailPage.<span xmlns:fo="http://www.w3.org/1999/XSL/Format" class="kwd">class</span>); |
| setRedirect(path + <span xmlns:fo="http://www.w3.org/1999/XSL/Format" class="str">"?id="</span> + id); |
| |
| <span xmlns:fo="http://www.w3.org/1999/XSL/Format" class="kwd">return</span> false; |
| } |
| }</pre><p>A quick way of redirecting to another page is to simply refer to the target |
| class. The example below logs a user out, by invalidating their session, and |
| then redirects them to the application home page. |
| </p><pre class="programlisting"><span xmlns:fo="http://www.w3.org/1999/XSL/Format" class="kwd">public</span> <span xmlns:fo="http://www.w3.org/1999/XSL/Format" class="kwd">boolean</span> onLogoutClick() { |
| getContext().getSession().invalidate(); |
| |
| setRedirect(HomePage.<span xmlns:fo="http://www.w3.org/1999/XSL/Format" class="kwd">class</span>); |
| |
| <span xmlns:fo="http://www.w3.org/1999/XSL/Format" class="kwd">return</span> false; |
| }</pre></div><div class="navfooter"><hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="ch06s03.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="ch06.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="ch06s05.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">6.3. Page Auto Mapping </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> 6.5. Templating</td></tr></table></div></body></html> |
