tapestry/src/site/xdoc/usersguide/events.xml - tapestry4 - Git at Google

 <?xml version="1.0" encoding="UTF-8"?>
 <!--
     Copyright 2005 The Apache Software Foundation

     Licensed under the Apache License, Version 2.0 (the "License");
     you may not use this file except in compliance with the License.
     You may obtain a copy of the License at

     http://www.apache.org/licenses/LICENSE-2.0

     Unless required by applicable law or agreed to in writing, software
     distributed under the License is distributed on an "AS IS" BASIS,
     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     See the License for the specific language governing permissions and
     limitations under the License.
 -->
 <document>
     <properties>
         <title>Page Events</title>
     </properties>
     <body>

         <section name="Page Events">
         <p>
             Tapestry component and page classes may implement
             <em>optional listener interfaces</em>
             . This interfaces allow the component (or page) to be notified when certain lifecycle
             events occur. Each interface consists of a single method.
         </p>

         <p>
             It is merely necessary to implement the interface; the framework will automatically
             register the component (or page) to receive the notification. It is perfectly acceptible
             to implement multiple interfaces.
         </p>

         <table>
             <tr>
                 <th>Interface</th>
                 <th>Invoked</th>
                 <th>Notes</th>
             </tr>
             <tr>
                 <td>
                     <a
                         href="../apidocs/org/apache/tapestry/event/PageAttachListener.html">
                         PageAttachListener
                     </a>
                 </td>
                 <td>
                     When a page is first attached to the current request. After the page's
                     persistent properties have been rolled back.
                 </td>
                 <td>
                     Set up the page's properties based on the current session state, possibly by
                     pulling data from an
                     <a href="state.html#state.aso">application state object</a>
                     .
                 </td>
             </tr>
             <tr>
                 <td>
                     <a
                         href="../apidocs/org/apache/tapestry/event/PageValidateListener.html">
                         PageValidateListener
                     </a>
                 </td>
                 <td>
                     When a page is activated (selected to render the reponse). Throw
                     <a
                         href="../apidocs/org/apache/tapestry/PageRedirectException.html">
                         PageRedirectException
                     </a>
                     to activate a different page.
                 </td>
                 <td>
                     Typically, checking the user's allowed access to a page, based on
                     application-specific security rules.
                 </td>
             </tr>
             <tr>
                 <td>
                     <a
                         href="../apidocs/org/apache/tapestry/event/PageBeginRenderListener.html">
                         PageBeginRenderListener
                     </a>
                 </td>
                 <td>
                     Just before the page begins to render. This is the last chance to update
                     persistent page properties.
                 </td>
                 <td />
             </tr>
             <tr>
                 <td>
                     <a
                         href="../apidocs/org/apache/tapestry/event/PageEndRenderListener.html">
                         PageEndRenderListener
                     </a>
                 </td>
                 <td>
                     At the end of the page render (even if an exception is thrown while the page
                     renders).
                 </td>
                 <td />
             </tr>
             <tr>
                 <td>
                     <a
                         href="../apidocs/org/apache/tapestry/event/PageDetachListener.html">
                         PageDetachListener
                     </a>
                 </td>
                 <td>
                     As the page is detached from the request and returned to the shared page pool.
                 </td>
                 <td>
                     Final cleanups to "scrub" the page, remove any client-specific state, and
                     otherwise return it to a pristine state.
                 </td>
             </tr>
         </table>

         <span class="info">
             <strong>Note:</strong>
             <p>
             Tapestry 3.0 defined a single
             <a
                 href="../apidocs/org/apache/tapestry/event/PageRenderListener.html">
                 PageRenderListener
             </a>
             interface instead of
             <a
                 href="../apidocs/org/apache/tapestry/event/PageBeginRenderListener.html">
                 PageBeginRenderListener
             </a>
             and
             <a
                 href="../apidocs/org/apache/tapestry/event/PageEndRenderListener.html">
                 PageEndRenderListener
             </a>
             . This is still supported in 4.0 (it has been redefined as extending the other two
             interfaces), but will likely be removed in a future release.
             </p>
         </span>

         </section>
     </body>
 </document>
	<?xml version="1.0" encoding="UTF-8"?>
	<!--
	Copyright 2005 The Apache Software Foundation

	Licensed under the Apache License, Version 2.0 (the "License");
	you may not use this file except in compliance with the License.
	You may obtain a copy of the License at

	http://www.apache.org/licenses/LICENSE-2.0

	Unless required by applicable law or agreed to in writing, software
	distributed under the License is distributed on an "AS IS" BASIS,
	WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	See the License for the specific language governing permissions and
	limitations under the License.
	-->
	<document>
	<properties>
	<title>Page Events</title>
	</properties>
	<body>

	<section name="Page Events">
	<p>
	Tapestry component and page classes may implement
	<em>optional listener interfaces</em>
	. This interfaces allow the component (or page) to be notified when certain lifecycle
	events occur. Each interface consists of a single method.
	</p>

	<p>
	It is merely necessary to implement the interface; the framework will automatically
	register the component (or page) to receive the notification. It is perfectly acceptible
	to implement multiple interfaces.
	</p>

	<table>
	<tr>
	<th>Interface</th>
	<th>Invoked</th>
	<th>Notes</th>
	</tr>
	<tr>
	<td>
	<a
	href="../apidocs/org/apache/tapestry/event/PageAttachListener.html">
	PageAttachListener
	</a>
	</td>
	<td>
	When a page is first attached to the current request. After the page's
	persistent properties have been rolled back.
	</td>
	<td>
	Set up the page's properties based on the current session state, possibly by
	pulling data from an
	<a href="state.html#state.aso">application state object</a>
	.
	</td>
	</tr>
	<tr>
	<td>
	<a
	href="../apidocs/org/apache/tapestry/event/PageValidateListener.html">
	PageValidateListener
	</a>
	</td>
	<td>
	When a page is activated (selected to render the reponse). Throw
	<a
	href="../apidocs/org/apache/tapestry/PageRedirectException.html">
	PageRedirectException
	</a>
	to activate a different page.
	</td>
	<td>
	Typically, checking the user's allowed access to a page, based on
	application-specific security rules.
	</td>
	</tr>
	<tr>
	<td>
	<a
	href="../apidocs/org/apache/tapestry/event/PageBeginRenderListener.html">
	PageBeginRenderListener
	</a>
	</td>
	<td>
	Just before the page begins to render. This is the last chance to update
	persistent page properties.
	</td>
	<td />
	</tr>
	<tr>
	<td>
	<a
	href="../apidocs/org/apache/tapestry/event/PageEndRenderListener.html">
	PageEndRenderListener
	</a>
	</td>
	<td>
	At the end of the page render (even if an exception is thrown while the page
	renders).
	</td>
	<td />
	</tr>
	<tr>
	<td>
	<a
	href="../apidocs/org/apache/tapestry/event/PageDetachListener.html">
	PageDetachListener
	</a>
	</td>
	<td>
	As the page is detached from the request and returned to the shared page pool.
	</td>
	<td>
	Final cleanups to "scrub" the page, remove any client-specific state, and
	otherwise return it to a pristine state.
	</td>
	</tr>
	</table>

	<span class="info">
	<strong>Note:</strong>
	<p>
	Tapestry 3.0 defined a single
	<a
	href="../apidocs/org/apache/tapestry/event/PageRenderListener.html">
	PageRenderListener
	</a>
	interface instead of
	<a
	href="../apidocs/org/apache/tapestry/event/PageBeginRenderListener.html">
	PageBeginRenderListener
	</a>
	and
	<a
	href="../apidocs/org/apache/tapestry/event/PageEndRenderListener.html">
	PageEndRenderListener
	</a>
	. This is still supported in 4.0 (it has been redefined as extending the other two
	interfaces), but will likely be removed in a future release.
	</p>
	</span>

	</section>
	</body>
	</document>