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Posted to dev@tapestry.apache.org by bu...@apache.org on 2015/04/04 00:19:43 UTC
svn commit: r946241 [2/2] - in /websites/production/tapestry/content: ./
cache/ error-page-recipe.data/ overriding-exception-reporting.data/
Modified: websites/production/tapestry/content/templating-and-markup-faq.html
==============================================================================
--- websites/production/tapestry/content/templating-and-markup-faq.html (original)
+++ websites/production/tapestry/content/templating-and-markup-faq.html Fri Apr 3 22:19:42 2015
@@ -82,7 +82,7 @@ table.ScrollbarTable td.ScrollbarNextIco
</div></div><p>Part of the DOCTYPE is the declaration of entities such as <code>&nbsp;</code>.</p><p>Alternately, you can simply use the numeric version: <code>&#160</code>; This is the exact same character and will render identically in the browser.</p><p>Starting in release 5.3, Tapestry introduces an XHTML doctype when no doctype is present; this means that common HTML entities will work correctly.</p><h3 id="TemplatingandMarkupFAQ-Whydosomeimagesinmypageshowupasbrokenlinks?">Why do some images in my page show up as broken links?</h3><p>You have to be careful when using relative URLs inside page templates; the base URL may not always be what you expect. For example, inside your <code>ViewUser.tml</code> file, you may have:</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl">
<script class="theme: Default; brush: xml; gutter: false" type="syntaxhighlighter"><![CDATA[ <img class="icon" src="icons/admin.png"/>${user.name} has Administrative access
]]></script>
-</div></div><p>This makes sense; <code>ViewUser.tml</code> is in the web context, as is the <code>icons</code> folder. The default URL for this page will be <code>/viewuser (assuming that ViewUser class is in the _root-package_.{{pages}} package).<br clear="none"></code></p><p>However, the ViewUser page might use a page activation context to identify which user is to be displayed:</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl">
+</div></div><p>This makes sense; ViewUser.tml is in the web context, as is the icons folder. The default URL for this page will be /viewuser (assuming that ViewUser class is in the  <em>root-package</em>.pages package).</p><p>However, the ViewUser page might use a page activation context to identify which user is to be displayed:</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl">
<script class="theme: Default; brush: java; gutter: false" type="syntaxhighlighter"><![CDATA[public class ViewUser
@Property
@@ -107,13 +107,7 @@ table.ScrollbarTable td.ScrollbarNextIco
</div></div><p>The other id is the client id, a unique id for the rendered element within the client-side DOM. JavaScript that needs to access the element uses this id. For example:</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl">
<script class="theme: Default; brush: text; gutter: false" type="syntaxhighlighter"><![CDATA[ $('status').hide();
]]></script>
-</div></div><p>In many components, the <code>id</code> attribute is an informal parameter; a value from the template that is blindly echoed into the output document. In other cases, the component itself has an <code>id</code> attribute. Often, in the latter case, the Tapestry component id is the <em>default</em> value for the client id.</p><h3 id="TemplatingandMarkupFAQ-WhydomyimagesandstylesheetsendupwithaweirdURLslike/assets/eea17aee26bc0cae/ctx/layout/layout.css?">Why do my images and stylesheets end up with a weird URLs like <code>/assets/eea17aee26bc0cae/ctx/layout/layout.css</code>?</h3><p>Tapestry doesn't rely on the servlet container to serve up your static assets (images, stylesheets, flash movies, etc.). Instead, Tapestry processes the requests itself, streaming assets to the browser.</p><p>Asset content will be GZIP compressed (if the client supports compression, and the content is compressible). In addition, Tapestry will set a far-future expires header on the content. T
his means that the browser will not ask for the file again, greatly reducing network traffic.</p><p>The weird hex string is a random application version number. A new one is chosen every time the application starts up.</p><p>This is necessary so that, if an asset changes in place, browsers will download the new version. Because the application version number has changed, it represents a new asset to browsers, who will download the new version, even if the old version was previously downloaded (remember the far future expires header).</p><p>By the time your application is ready for production, you should manage the application version number directly:</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeHeader panelHeader pdl" style="border-bottom-width: 1px;"><b>AppModule.java (partial)</b></div><div class="codeContent panelContent pdl">
-<script class="theme: Default; brush: java; gutter: false" type="syntaxhighlighter"><![CDATA[ public static void contributeApplicationDefaults(
- MappedConfiguration<String, String> configuration) {
- configuration.add(SymbolConstants.APPLICATION_VERSION, "1.7.5");
- }
-]]></script>
-</div></div><p>You should be careful to change the application version number for each new deployment of your application; otherwise returning users may be stuck with old versions of assets that have changed in the interim. This kind of mismatch can cause visual annoyances for style sheets or image files, but can break client-side behavior for changed JavaScript libraries.</p><h3 id="TemplatingandMarkupFAQ-HowdoIaddaCSSclasstoaTapestrycomponent?">How do I add a CSS class to a Tapestry component?</h3><p>As they say, "just do it". The majority of Tapestry components support <em>informal parameters</em>, meaning that any extra attributes in the element (in the template) will be rendered out as additional attributes. So, you can apply a CSS class or style quite easily:</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl">
+</div></div><p>In many components, the <code>id</code> attribute is an informal parameter; a value from the template that is blindly echoed into the output document. In other cases, the component itself has an <code>id</code> attribute. Often, in the latter case, the Tapestry component id is the <em>default</em> value for the client id.</p><h3 id="TemplatingandMarkupFAQ-WhydomyimagesandstylesheetsendupwithaweirdURLslike/assets/meta/zeea17aee26bc0cae/layout/layout.css?">Why do my images and stylesheets end up with a weird URLs like <code>/assets/meta/zeea17aee26bc0cae/layout/layout.css</code>?</h3><p>Tapestry doesn't rely on the servlet container to serve up your static assets (images, stylesheets, flash movies, etc.). Instead, Tapestry processes the requests itself, streaming assets to the browser.</p><p>Asset content will be GZIP compressed (if the client supports compression, and the content is compressible). In addition, Tapestry will set a far-future expires header on the conten
t. This means that the browser will not ask for the file again, greatly reducing network traffic.</p><p>The weird hex string is a <em>fingerprint</em>; it is a hash code computed from the actual content of the asset. If the asset every changes, it will have a new fingerprint, and so will be a new path and a new (immutable) resource. This approach, combined with a far-future expires header also provided by Tapestry, ensures that clients aggressively cache assets as they navigate your site, or even between visits.</p><p><span style="color: rgb(83,145,38);font-size: 16.0px;line-height: 1.5625;">How do I add a CSS class to a Tapestry component?</span></p><p>As they say, "just do it". The majority of Tapestry components support <em>informal parameters</em>, meaning that any extra attributes in the element (in the template) will be rendered out as additional attributes. So, you can apply a CSS class or style quite easily:</p><div class="code panel pdl" style="border-width: 1px;"><div
class="codeContent panelContent pdl">
<script class="theme: Default; brush: xml; gutter: false" type="syntaxhighlighter"><![CDATA[ <t:textfield t:id="username" class="big-green"/>
]]></script>
</div></div><p>You can even use template expansions inside the attribute value:</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl">
@@ -133,7 +127,7 @@ table.ScrollbarTable td.ScrollbarParent
table.ScrollbarTable td.ScrollbarNextName {text-align: right;border: none;}
table.ScrollbarTable td.ScrollbarNextIcon {text-align: center;width: 16px;border: none;}
-/*]]>*/</style><div class="Scrollbar"><table class="ScrollbarTable"><tr><td colspan="1" rowspan="1" class="ScrollbarPrevIcon"><a shape="rect" href="general-questions.html"><img align="middle" border="0" src="https://cwiki.apache.org/confluence/images/icons/back_16.gif" width="16" height="16"></a></td><td colspan="1" rowspan="1" class="ScrollbarPrevName" width="33%"><a shape="rect" href="general-questions.html">General Questions</a> </td><td colspan="1" rowspan="1" class="ScrollbarParent" width="33%"><sup><a shape="rect" href="frequently-asked-questions.html"><img align="middle" border="0" src="https://cwiki.apache.org/confluence/images/icons/up_16.gif" width="8" height="8"></a></sup><a shape="rect" href="frequently-asked-questions.html">Frequently Asked Questions</a></td><td colspan="1" rowspan="1" class="ScrollbarNextName" width="33%"> <a shape="rect" href="page-and-component-classes-faq.html">Page And Component Classes FAQ</a></td><td colspan="1" rowspan="1" class="Scrol
lbarNextIcon"><a shape="rect" href="page-and-component-classes-faq.html"><img align="middle" border="0" src="https://cwiki.apache.org/confluence/images/icons/forwd_16.gif" width="16" height="16"></a></td></tr></table></div><p> </p><p> </p><p> </p><p> </p><p> </p><p> </p><p><table class="Footnotes" style="width: 100%; border:none;" cellspacing="0" cellpadding="0" summary="This table contains one or more notes for references made elsewhere on the page."><caption class="accessibility">Footnotes</caption><thead class="accessibility"><tr class="accessibility"><th colspan="1" rowspan="1" class="accessibility" id="footnote-th1">Reference</th><th colspan="1" rowspan="1" class="accessibility" id="footnote-th2">Notes</th></tr></thead><tbody></tbody></table></p><p> </p><p> </p><p> </p><p> </p></div>
+/*]]>*/</style><div class="Scrollbar"><table class="ScrollbarTable"><tr><td colspan="1" rowspan="1" class="ScrollbarPrevIcon"><a shape="rect" href="general-questions.html"><img align="middle" border="0" src="https://cwiki.apache.org/confluence/images/icons/back_16.gif" width="16" height="16"></a></td><td colspan="1" rowspan="1" class="ScrollbarPrevName" width="33%"><a shape="rect" href="general-questions.html">General Questions</a> </td><td colspan="1" rowspan="1" class="ScrollbarParent" width="33%"><sup><a shape="rect" href="frequently-asked-questions.html"><img align="middle" border="0" src="https://cwiki.apache.org/confluence/images/icons/up_16.gif" width="8" height="8"></a></sup><a shape="rect" href="frequently-asked-questions.html">Frequently Asked Questions</a></td><td colspan="1" rowspan="1" class="ScrollbarNextName" width="33%"> <a shape="rect" href="page-and-component-classes-faq.html">Page And Component Classes FAQ</a></td><td colspan="1" rowspan="1" class="Scrol
lbarNextIcon"><a shape="rect" href="page-and-component-classes-faq.html"><img align="middle" border="0" src="https://cwiki.apache.org/confluence/images/icons/forwd_16.gif" width="16" height="16"></a></td></tr></table></div><p> </p><p> </p><p> </p><p> </p><p> </p><p> </p><table class="Footnotes" style="width: 100%; border:none;" cellspacing="0" cellpadding="0" summary="This table contains one or more notes for references made elsewhere on the page."><caption class="accessibility">Footnotes</caption><thead class="accessibility"><tr class="accessibility"><th colspan="1" rowspan="1" class="accessibility" id="footnote-th1">Reference</th><th colspan="1" rowspan="1" class="accessibility" id="footnote-th2">Notes</th></tr></thead><tbody></tbody></table><p> </p><p> </p><p> </p><p> </p></div>
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