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Posted to commits@tapestry.apache.org by bu...@apache.org on 2018/02/13 02:20:37 UTC
svn commit: r1025319 - in /websites/production/tapestry/content:
cache/main.pageCache component-parameters.html
overriding-exception-reporting.html switching-cases.html
Author: buildbot
Date: Tue Feb 13 02:20:37 2018
New Revision: 1025319
Log:
Production update by buildbot for tapestry
Modified:
websites/production/tapestry/content/cache/main.pageCache
websites/production/tapestry/content/component-parameters.html
websites/production/tapestry/content/overriding-exception-reporting.html
websites/production/tapestry/content/switching-cases.html
Modified: websites/production/tapestry/content/cache/main.pageCache
==============================================================================
Binary files - no diff available.
Modified: websites/production/tapestry/content/component-parameters.html
==============================================================================
--- websites/production/tapestry/content/component-parameters.html (original)
+++ websites/production/tapestry/content/component-parameters.html Tue Feb 13 02:20:37 2018
@@ -180,11 +180,11 @@
</div></div><p>A component may have any number of parameters. Each parameter has a specific name, a specific Java type (which may be a primitive value), and may be <em>optional</em> or <em>required</em>.</p><p>Within a component class, parameters are declared by using the @<a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/annotations/Parameter.html">Parameter</a> annotation on a private field, as we'll see below.</p><p><span class="confluence-anchor-link" id="ComponentParameters-bindingparameters"></span></p><h1 id="ComponentParameters-ParameterBindings">Parameter Bindings</h1><p>In Tapestry, a parameter is not a slot into which data is pushed: it is a <em>connection</em> between a field of the component (marked with the @Parameter annotation) and a property or resource of the component's container. (Components can be nested, so the container can be either the page or another component.)</p><div class="navmenu" style="float:right; backgr
ound:white; margin:3px; padding:3px">
<div class="panel" style="border-width: 1px;"><div class="panelHeader" style="border-bottom-width: 1px;"><b>Contents</b></div><div class="panelContent">
<style type="text/css">/*<![CDATA[*/
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<ul class="toc-indentation"><li><a href="#ComponentParameters-ParameterBindings">Parameter Bindings</a></li><li><a href="#ComponentParameters-BindingExpressions">Binding Expressions</a></li><li><a href="#ComponentParameters-@Parameterannotation">@Parameter annotation</a></li><li><a href="#ComponentParameters-Don'tusethe${...}syntax!">Don't use the ${...} syntax!</a></li><li><a href="#ComponentParameters-InformalParameters">Informal Parameters</a></li><li><a href="#ComponentParameters-ParametersAreBi-Directional">Parameters Are Bi-Directional</a></li><li><a href="#ComponentParameters-InheritedParameterBindings">Inherited Parameter Bindings</a></li><li><a href="#ComponentParameters-ComputedParameterBindingDefaults">Computed Parameter Binding Defaults</a></li><li><a href="#ComponentParameters-UnboundParameters">Unbound Parameters</a></li><li><a href="#ComponentParameters-ParameterTypeCoercion">Parameter Type Coercion</a></li><li><a href="#ComponentParameters-ParameterNames">
Parameter Names</a></li><li><a href="#ComponentParameters-DeterminingifBound">Determining if Bound</a></li><li><a href="#ComponentParameters-PublishingParameters">Publishing Parameters</a></li></ul>
</div>
</div></div></div> <p>The connection between a component and a property (or resource) of its container is called a <em>binding</em>. The binding is two-way: the component can read the bound property by reading its parameter field. Likewise, a component that updates its parameter field will update the bound property.</p><p>This is important in a lot of cases; for example a TextField component can read <em>and update</em> the property bound to its value parameter. It reads the value when rendering, but updates the value when the form is submitted.</p><p>The component listed below is a looping component; it renders its body a number of times, defined by its <code>start</code> and <code>end</code> parameters (which set the boundaries of the loop). The component can update a <code>result</code> parameter bound to a property of its container; it will automatically count up or down depending on whether <code>start</code> or <code>end</code> is larger.</p><div class="code panel pdl" st
yle="border-width: 1px;"><div class="codeContent panelContent pdl">
@@ -261,7 +261,7 @@ private int index;
</ul>
</pre>
-</div></div><p>In other words, you don't have to define a property in the Java code. The disadvantage is that render variables don't work with the property expression syntax, so you can pass around a render variable's <em>value</em> but you can't reference any of the value's properties.</p><p>Render variables are automatically cleared when a component finishes rendering.</p><p>Render variable names are case insensitive.</p><h3 id="ComponentParameters-Property:Bindings">Property: Bindings</h3><p>The "prop:" binding prefix indicates a property expression binding.</p><p>Property expressions are used to link a parameter of a component to a property of its container. Property expressions can navigate a series of properties and/or invoke methods, as well as several other useful patterns. See <a href="component-parameters.html">Component Parameters</a>.</p><p>The default binding prefix in most cases is "prop:", which is why it is usually omitted.</p><h3 id="ComponentParameters-Validate:Bi
ndings">Validate: Bindings</h3><p>Main Article: <a href="component-parameters.html">Component Parameters</a></p><p>The "validate:" binding prefix is highly specialized. It allows a short string to be used to create and configure the objects that perform input validation for form control components, such as TextField and Checkbox.</p><p>The string is a comma-separated list of <em>validator types</em>. These are short aliases for objects that perform the validation. In many cases, the validation is configurable in some way: for example, a validator that enforces a minimum string length needs to know what that minimum string length is. Such values are specified after an equals sign.</p><p>For example: <code>validate:required,minLength=5</code> would presumably enforce that a field requires a value, and with at least five characters.</p><h3 id="ComponentParameters-Translate:Bindings">Translate: Bindings</h3><p>The "translate:" binding prefix is also related to input validation. It is t
he name of a configured <a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/Translator.html">Translator</a>, responsible for converting between server-side and client-side representations of data (for instance, between client-side strings and server-side numeric values).</p><p>The list of available translators is configured by the <a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/services/TranslatorSource.html">TranslatorSource</a> service.</p><h3 id="ComponentParameters-Asset:Bindings">Asset: Bindings</h3><p>Assets bindings are used to specify <a href="component-parameters.html">Component Parameters</a>, static content served by Tapestry. By default, assets are located relative to the component class in your packaged application or module. This can be overridden by prefixing the path with "context:", in which case, the path is a context path from the root of the web application context. Becau
se accessing context assets is relatively common, a separate "context:" binding prefix for that purpose exists (described below).</p><h3 id="ComponentParameters-Context:Bindings">Context: Bindings</h3><p>Context bindings are like asset bindings, but the path is <em>always</em> relative to the root of the web application context. This is intended for use inside templates, i.e.:</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl">
+</div></div><p>In other words, you don't have to define a property in the Java code. The disadvantage is that render variables don't work with the property expression syntax, so you can pass around a render variable's <em>value</em> but you can't reference any of the value's properties.</p><p>Render variables are automatically cleared when a component finishes rendering.</p><p>Render variable names are case insensitive.</p><h3 id="ComponentParameters-Property:Bindings">Property: Bindings</h3><p>Main Article: <a href="property-expressions.html">Property Expressions</a></p><p>The "prop:" binding prefix indicates a property expression binding.</p><p>Property expressions are used to link a parameter of a component to a property of its container. Property expressions can navigate a series of properties and/or invoke methods, as well as several other useful patterns.</p><p>The default binding prefix in most cases is "prop:", which is why it is usually omitted.</p><h3 id="ComponentParamet
ers-Validate:Bindings">Validate: Bindings</h3><p>Main Article: <a href="forms-and-validation.html">Forms and Validation</a></p><p>The "validate:" binding prefix is highly specialized. It allows a short string to be used to create and configure the objects that perform input validation for form control components, such as TextField and Checkbox.</p><p>The string is a comma-separated list of <em>validator types</em>. These are short aliases for objects that perform the validation. In many cases, the validation is configurable in some way: for example, a validator that enforces a minimum string length needs to know what that minimum string length is. Such values are specified after an equals sign.</p><p>For example: <code>validate:required,minLength=5</code> would presumably enforce that a field requires a value, and with at least five characters.</p><h3 id="ComponentParameters-Translate:Bindings">Translate: Bindings</h3><p>The "translate:" binding prefix is also related to input vali
dation. It is the name of a configured <a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/Translator.html">Translator</a>, responsible for converting between server-side and client-side representations of data (for instance, between client-side strings and server-side numeric values).</p><p>The list of available translators is configured by the <a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/services/TranslatorSource.html">TranslatorSource</a> service.</p><h3 id="ComponentParameters-Asset:Bindings">Asset: Bindings</h3><p>Main Article: <a href="assets.html">Assets</a></p><p>Assets bindings are used to specify <a href="component-parameters.html">Component Parameters</a>, static content served by Tapestry. By default, assets are located relative to the component class in your packaged application or module. This can be overridden by prefixing the path with "context:", in which case, the path
is a context path from the root of the web application context. Because accessing context assets is relatively common, a separate "context:" binding prefix for that purpose exists (described below).</p><h3 id="ComponentParameters-Context:Bindings">Context: Bindings</h3><p>Main Article: <a href="assets.html">Assets</a></p><p>Context bindings are like asset bindings, but the path is <em>always</em> relative to the root of the web application context. This is intended for use inside templates, i.e.:</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl">
<pre class="brush: xml; gutter: false; theme: Default" style="font-size:12px;"> <img src="${context:images/icon.png}"/>
</pre>
</div></div><p>Tapestry will adjust the URL of the image so that it is processed by Tapestry, not the servlet container. It will gain a URL that includes the application's version number, it will have a far-future expires header, and (if the client supports it) its content will be compressed before being sent to the client.</p><h1 id="ComponentParameters-@Parameterannotation">@Parameter annotation</h1><h3 id="ComponentParameters-RequiredParameters">Required Parameters</h3><p>Parameters that are required <strong>must</strong> be bound. A runtime exception occurs if a component has unbound required parameters.</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl">
@@ -295,7 +295,7 @@ public String getDefaultMessage(){ 
</div></div></div><div class="columnMacro"><div class="code panel pdl" style="border-width: 1px;"><div class="codeHeader panelHeader pdl" style="border-bottom-width: 1px;"><b>This is wrong</b></div><div class="codeContent panelContent pdl">
<pre class="brush: xml; gutter: false; theme: Default" style="font-size:12px;"><img src="context:images/banner.png"/>
</pre>
-</div></div></div></div></div></div><h1 id="ComponentParameters-InformalParameters">Informal Parameters</h1><p>Main Article: <a href="component-parameters.html">Component Parameters</a></p><p>Many components support <em>informal parameters</em>, additional parameters beyond the formally defined parameters. Informal parameters will be rendered into the output as additional attributes on the tag rendered by the component. Generally speaking, components that have a 1:1 relationship with a particular HTML tag (such as <TextField> and <input> will support informal parameters.</p><p>Only components whose class is annotated with @<a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/annotations/SupportsInformalParameters.html">SupportsInformalParameters</a> will support informal parameters. Tapestry silently drops informal parameters that are specified for components that do not have this annotation.</p><p>Informal parameters are often
used to set the CSS class of an element, or to specify client-side event handlers.</p><p>The default binding prefix for informal parameters depends on <em>where</em> the parameter binding is specified. If the parameter is bound inside a Java class, within the @<a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/annotations/Component.html">Component</a> annotation, then the default binding prefix is "prop:". If the parameter is bound inside the component template, then the default binding prefix is "literal:". This reflects the fact that a parameter specified in the Java class, using the annotation, is most likely a computed value, whereas a value in the template should simply be copied, as is, into the result HTML stream.</p><p>Informal parameters (if supported) are always rendered into the output <em>unless</em> they are bound to a property whose value is null. If the bound property is null then the parameter will <em>not</em> be present
at all in the rendered output.</p><p>If your component should render informal parameters, just inject the <a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/ComponentResources.html">ComponentResources</a> for your component and invoke the <code>renderInformalParameters()</code> method. See <a href="component-parameters.html">Component Parameters</a> for an example of how to do this.</p><h1 id="ComponentParameters-ParametersAreBi-Directional">Parameters Are Bi-Directional</h1><p>Parameters are not simply variables; each parameter represents a connection, or <em>binding</em>, between a component and a property of its container. When using the prop: binding prefix, the component can force changes <em>into</em> a property of its container, just by assigning a value to its own instance variable.</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl">
+</div></div></div></div></div></div><h1 id="ComponentParameters-InformalParameters">Informal Parameters</h1><p>Main Article: <a href="supporting-informal-parameters.html">Supporting Informal Parameters</a></p><p>Many components support <em>informal parameters</em>, additional parameters beyond the formally defined parameters. Informal parameters will be rendered into the output as additional attributes on the tag rendered by the component. Generally speaking, components that have a 1:1 relationship with a particular HTML tag (such as <TextField> and <input> will support informal parameters.</p><p>Only components whose class is annotated with @<a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/annotations/SupportsInformalParameters.html">SupportsInformalParameters</a> will support informal parameters. Tapestry silently drops informal parameters that are specified for components that do not have this annotation.</p><p>Informal
parameters are often used to set the CSS class of an element, or to specify client-side event handlers.</p><p>The default binding prefix for informal parameters depends on <em>where</em> the parameter binding is specified. If the parameter is bound inside a Java class, within the @<a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/annotations/Component.html">Component</a> annotation, then the default binding prefix is "prop:". If the parameter is bound inside the component template, then the default binding prefix is "literal:". This reflects the fact that a parameter specified in the Java class, using the annotation, is most likely a computed value, whereas a value in the template should simply be copied, as is, into the result HTML stream.</p><p>Informal parameters (if supported) are always rendered into the output <em>unless</em> they are bound to a property whose value is null. If the bound property is null then the parameter will <em
>not</em> be present at all in the rendered output.</p><p>If your component should render informal parameters, just inject the <a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/ComponentResources.html">ComponentResources</a> for your component and invoke the <code>renderInformalParameters()</code> method. See <a href="supporting-informal-parameters.html">Supporting Informal Parameters</a> for an example of how to do this.</p><h1 id="ComponentParameters-ParametersAreBi-Directional">Parameters Are Bi-Directional</h1><p>Parameters are not simply variables; each parameter represents a connection, or <em>binding</em>, between a component and a property of its container. When using the prop: binding prefix, the component can force changes <em>into</em> a property of its container, just by assigning a value to its own instance variable.</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl">
<pre class="brush: xml; gutter: false; theme: Default" style="font-size:12px;"><t:layout xmlns:t="http://tapestry.apache.org/schema/tapestry_5_3.xsd">
<p> Countdown:
<t:count start="5" end="1" result="index">
@@ -375,7 +375,7 @@ public class Title {
return String.format("Maximum field length is %d.", maxLength);
}
</pre>
-</div></div><p>This form is more like using the "literal:" binding prefix, except that the literal value is computed by the defaultMessage() method.</p><p>Obviously, this is a lot more work than simply specifying a default value as part of the @Parameter annotation. In the few real cases where this is approach is used, the default binding method will usually deduce a proper binding, typically in terms of the component's id. For example, the TextField component will deduce a value parameter that binds to a property of its container with the same name.</p><p>A default binding method will <em>only</em> be invoked if the @Parameter annotation does not provide a default value.</p><h1 id="ComponentParameters-UnboundParameters">Unbound Parameters</h1><p>If a parameter is not bound (and is optional), then the value may be read or <em>updated</em> at any time.</p><p>Updates to unbound parameters cause no side effects. In the first example, the value parameter of the Count component is not bo
und, and this is perfectly valid.</p><p>Note: updates to such fields are temporary; when the component <em>finishes rendering</em>, the field will revert to its default value.</p><h1 id="ComponentParameters-ParameterTypeCoercion">Parameter Type Coercion</h1><p>Main Article: <a href="component-parameters.html">Component Parameters</a></p><p>Tapestry includes a mechanism for <span class="confluence-link">coercing types automatically</span>. Most often, this is used to convert literal strings into appropriate values, but in many cases, more complex conversions will occur. This mechanism is used for component parameters, such as when an outer component passes a literal string to an inner component that is expecting an integer.</p><p>You can easily <a href="component-parameters.html">contribute new coercions</a> for your own purposes.</p><h1 id="ComponentParameters-ParameterNames">Parameter Names</h1><p>By default, Tapestry converts from the field name to the parameter name, by strippi
ng off leading "$" and "_" characters.</p><p>This can be overridden using the name() attribute of the @Parameter annotation.</p><h1 id="ComponentParameters-DeterminingifBound">Determining if Bound</h1><p>In rare cases, you may want to take different behaviors based on whether a parameter is bound or not. This can be accomplished by querying the component's resources, which can be <a href="component-parameters.html">injected</a> into the component using the @<a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/ioc/annotations/Inject.html">Inject</a> annotation:</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl">
+</div></div><p>This form is more like using the "literal:" binding prefix, except that the literal value is computed by the defaultMessage() method.</p><p>Obviously, this is a lot more work than simply specifying a default value as part of the @Parameter annotation. In the few real cases where this is approach is used, the default binding method will usually deduce a proper binding, typically in terms of the component's id. For example, the TextField component will deduce a value parameter that binds to a property of its container with the same name.</p><p>A default binding method will <em>only</em> be invoked if the @Parameter annotation does not provide a default value.</p><h1 id="ComponentParameters-UnboundParameters">Unbound Parameters</h1><p>If a parameter is not bound (and is optional), then the value may be read or <em>updated</em> at any time.</p><p>Updates to unbound parameters cause no side effects. In the first example, the value parameter of the Count component is not bo
und, and this is perfectly valid.</p><p>Note: updates to such fields are temporary; when the component <em>finishes rendering</em>, the field will revert to its default value.</p><h1 id="ComponentParameters-ParameterTypeCoercion">Parameter Type Coercion</h1><p>Main Article: <a href="parameter-type-coercion.html">Parameter Type Coercion</a> </p><p>Tapestry includes a mechanism for <span class="confluence-link">coercing types automatically</span>. Most often, this is used to convert literal strings into appropriate values, but in many cases, more complex conversions will occur. This mechanism is used for component parameters, such as when an outer component passes a literal string to an inner component that is expecting an integer.</p><p>You can easily <a href="component-parameters.html">contribute new coercions</a> for your own purposes.</p><h1 id="ComponentParameters-ParameterNames">Parameter Names</h1><p>By default, Tapestry converts from the field name to the parameter name
, by stripping off leading "$" and "_" characters.</p><p>This can be overridden using the name() attribute of the @Parameter annotation.</p><h1 id="ComponentParameters-DeterminingifBound">Determining if Bound</h1><p>In rare cases, you may want to take different behaviors based on whether a parameter is bound or not. This can be accomplished by querying the component's resources, which can be <a href="component-parameters.html">injected</a> into the component using the @<a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/ioc/annotations/Inject.html">Inject</a> annotation:</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl">
<pre class="brush: java; gutter: false; theme: Default" style="font-size:12px;">public class MyComponent
{
@Parameter
Modified: websites/production/tapestry/content/overriding-exception-reporting.html
==============================================================================
--- websites/production/tapestry/content/overriding-exception-reporting.html (original)
+++ websites/production/tapestry/content/overriding-exception-reporting.html Tue Feb 13 02:20:37 2018
@@ -118,7 +118,7 @@
</div>
-<p>Of course, one of the first questions anyone asks is "How do I turn it off?" This exception reporting is very helpful for developers but its easy to see it as terrifying for potential users. Catching runtime exceptions can be a very useful way of handling rarely occurring exceptions even in production, and there's no reason to throw away Tapestry's default error reporting just to handle a few specific exceptions. From version 5.4 (for previous versions, the same functionality is available as a <a class="external-link" href="http://www.tynamo.org/tapestry-exceptionpage+guide/" rel="nofollow">third-party module tapestry-exceptionpage</a>), you can contribute exception handles and/or exception pages for specific exception types. Refer back to <a href="overriding-exception-reporting.html">Overriding Exception Reporting</a> page for more information. Read on if you want to completely replace Tapestry's default exception handling.</p><h2 id="OverridingExceptionReporting-Version1:Repl
acingtheExceptionReportPage">Version 1: Replacing the Exception Report Page</h2><p>Let's start with a page that fires an exception from an event handler method.</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeHeader panelHeader pdl" style="border-bottom-width: 1px;"><b>ActionFail.tml</b></div><div class="codeContent panelContent pdl">
+<p>Of course, one of the first questions anyone asks is "How do I turn it off?" This exception reporting is very helpful for developers but its easy to see it as terrifying for potential users. Catching runtime exceptions can be a very useful way of handling rarely occurring exceptions even in production, and there's no reason to throw away Tapestry's default error reporting just to handle a few specific exceptions. From version 5.4 (for previous versions, the same functionality is available as a <a class="external-link" href="http://www.tynamo.org/tapestry-exceptionpage+guide/" rel="nofollow">third-party module tapestry-exceptionpage</a>), you can contribute exception handles and/or exception pages for specific exception types. Refer back to <a href="runtime-exceptions.html">Runtime Exceptions</a> page for more information. Read on if you want to completely replace Tapestry's default exception handling.</p><h2 id="OverridingExceptionReporting-Version1:ReplacingtheExceptionRe
portPage">Version 1: Replacing the Exception Report Page</h2><p>Let's start with a page that fires an exception from an event handler method.</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeHeader panelHeader pdl" style="border-bottom-width: 1px;"><b>ActionFail.tml</b></div><div class="codeContent panelContent pdl">
<pre class="brush: xml; gutter: false; theme: Default" style="font-size:12px;"> <html xmlns:t="http://tapestry.apache.org/schema/tapestry_5_4.xsd" t:type="layout" title="Action Fail">
<p>
<t:actionlink t:id="fail" class="btn btn-large btn-warning">Click for Exception</t:actionlink>
Modified: websites/production/tapestry/content/switching-cases.html
==============================================================================
--- websites/production/tapestry/content/switching-cases.html (original)
+++ websites/production/tapestry/content/switching-cases.html Tue Feb 13 02:20:37 2018
@@ -80,7 +80,7 @@
<div id="ConfluenceContent"><p> </p><h1 id="SwitchingCases-SwitchingCases">Switching Cases</h1><p>With Tapestry's <code>If</code> component you can only test one condition at a time. In order to distinguish multiple cases, you'd have to write complex nested if/else constructs in your page template and have a checker method for each test inside your page class.</p><div class="navmenu" style="float:right; background:#eee; margin:3px; padding:0 1em">
<p> <strong>JumpStart Demo:</strong><br clear="none">
<a class="external-link" href="http://jumpstart.doublenegative.com.au/jumpstart/examples/lang/ifnotnegateswitchelseunless" rel="nofollow">If, Not, Negate, Switch, Else, Unless</a></p></div>In cases where you have to distinguish multiple cases, the <code>Delegate</code> component comes in. It delegates rendering to some other component, for example a <code>Block</code>. For each case you have, you basically wrap the content inside a <code>Block</code> that doesn't get rendered by default. You then place a Delegate component on your page and point it to a method inside your page class that will decide which of your Blocks should be rendered.<p>Imagine for example a use case, where you want to distinguish between 4 cases and you have an int property called <code>whichCase</code> that should be tested against. Your page template would look as follows:</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeHeader panelHeader pdl" style="border-bottom-width: 1px;">
<b>SwitchMe.tml</b></div><div class="codeContent panelContent pdl">
-<pre class="brush: xml; gutter: false; theme: Default" style="font-size:12px;"><html xmlns:t="http://tapestry.apache.org/schema/tapestry_5_1_0.xsd">
+<pre class="brush: xml; gutter: false; theme: Default" style="font-size:12px;"><html xmlns:t="http://tapestry.apache.org/schema/tapestry_5_4.xsd">
<body>
<h1>Switch</h1>