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| <document> |
| <properties> |
| <title>Component Bindings</title> |
| </properties> |
| <body> |
| |
| <section name="Component Bindings"> |
| <p> |
| Components are configured by |
| <em>binding</em> |
| their parameters. Binding of parameters may occur inside a page or component template, |
| or a page or component specification. |
| </p> |
| |
| <p> |
| When binding a component parameter, the value to be bound may be just a literal string, |
| or it could be an |
| <a href="http://www.ognl.org">OGNL</a> |
| expression, or subject to any of a number of other interpretations. Tapestry uses a |
| <em>prefix</em> |
| value, such as <code>ognl:</code>, or <code>message:</code>, to identify how the rest of the value is to be |
| interpreted. The prefix identifies the |
| <em>binding type</em> |
| : |
| </p> |
| |
| |
| <table> |
| <tr> |
| <th>Binding Type</th> |
| <th>Description</th> |
| <th>Example</th> |
| <th>OGNL Equivalent</th> |
| </tr> |
| |
| <tr> |
| <td>asset</td> |
| <td>References an asset of the component.</td> |
| <td>asset:stylesheet</td> |
| <td>ognl:assets.stylesheet</td> |
| </tr> |
| |
| <tr> |
| <td>bean</td> |
| <td> |
| References a named bean (defined by a |
| <a href="spec.html#spec.bean"><bean></a> |
| element). |
| </td> |
| <td>bean:validationDelegate</td> |
| <td>ognl:beans.validationDelegate</td> |
| </tr> |
| |
| <tr> |
| <td>clientId</td> |
| <td>The clientId of the given component.</td> |
| <td>clientId:myForm</td> |
| <td>ognl:components.myForm.clientId</td> |
| </tr> |
| |
| <tr> |
| <td>component</td> |
| <td>References a nested component with the provided component id.</td> |
| <td>component:form</td> |
| <td>ognl:components.form</td> |
| </tr> |
| |
| <tr> |
| <td>hivemind</td> |
| <td> |
| References a HiveMind object, much like |
| <a href="spec.html#spec.inject"><inject></a> |
| . |
| </td> |
| <td>hivemind:service:app.MyService</td> |
| <td /> |
| </tr> |
| |
| <tr> |
| <td>listener</td> |
| <td> |
| The name of a |
| <a href="listenermethods.html">listener method</a> |
| . |
| </td> |
| <td>listener:formSubmit</td> |
| <td>ognl:listeners.formSubmit</td> |
| </tr> |
| |
| <tr> |
| <td>literal</td> |
| <td>Used to "escape" a binding prefix, marking the suffix as a literal value.</td> |
| <td>literal:ognl:not-an-expression</td> |
| <td /> |
| </tr> |
| |
| <tr> |
| <td>message</td> |
| <td>References a localized message from the component's message catalog.</td> |
| <td>message:page-title</td> |
| <td>ognl:messages.getMessage("page-title")</td> |
| </tr> |
| |
| <tr> |
| <td>meta</td> |
| <td>References a meta configured value for a specific component/page or global configuration file. (such as APPNAME.application or FooComponent.jwc)</td> |
| <td>meta:renderIfTags</td> |
| <td>n/a</td> |
| </tr> |
| |
| <tr> |
| <td>ognl</td> |
| <td>An OGNL expression to be evaluated.</td> |
| <td>ognl:engine.visit.admin</td> |
| <td /> |
| </tr> |
| |
| <tr> |
| <td>state</td> |
| <td> |
| True of false dependening on whether the named |
| <a href="state.html#state.aso">application state object</a> |
| exists. |
| </td> |
| <td>state:visit</td> |
| <td /> |
| </tr> |
| |
| <tr> |
| <td>translator</td> |
| <td> |
| Initializer used to obtain and configure a |
| <a |
| href="../apidocs/org/apache/tapestry/form/translator/Translator.html"> |
| Translator |
| </a> |
| instance. |
| </td> |
| <td>translator:number,pattern=#</td> |
| <td /> |
| </tr> |
| <tr> |
| <td>validators</td> |
| <td> |
| List of configured |
| <a |
| href="../apidocs/org/apache/tapestry/form/validator/Validator.html"> |
| Validator |
| </a> |
| instances (used with |
| <a href="../components/form/textfield.html">TextField</a> |
| and others). |
| </td> |
| <td>validators:email,required,minLength=10</td> |
| <td /> |
| </tr> |
| </table> |
| |
| <p> |
| Most of these are quite straight forward; the |
| <a href="validation.html#validation.validator-binding"> |
| validator, validators and translator |
| </a> |
| prefixes require some additional description. |
| </p> |
| |
| <span class="info"> |
| <strong>Note:</strong> |
| <p> |
| You can define your own prefixes by contributing into the |
| <a href="../tapestry-framework/hivedoc/config/tapestry.bindings.BindingFactories.html">tapestry.bindings.BindingFactories</a> configuration point. |
| </p> |
| </span> |
| |
| <p> |
| What happens when you omit a binding prefix? In a page or component |
| <em>template</em> |
| , the value it is assumed to be a literal string, as with the "literal:" prefix. In a |
| page or component specification, or inside a Java annotation, the value is assumed to be |
| an |
| <a href="http://www.ognl.org">OGNL</a> |
| expression, as with the "ognl:" prefix (but even this can be configured). You will |
| occasionally have to use an explicit "literal:" prefix inside such files. |
| </p> |
| |
| |
| <p> |
| Many of the bindings are driven by a HiveMind configuration; the configuration will |
| define the available values, and contributing the configuration allows new values to be |
| defined. |
| </p> |
| |
| <table> |
| <tr> |
| <th>Binding Prefix</th> |
| <th>Configuration</th> |
| </tr> |
| <tr> |
| <td>translator</td> |
| <td> |
| <a |
| href="../tapestry-framework/hivedoc/config/tapestry.form.translator.Translators.html"> |
| tapestry.form.translator.Translators |
| </a> |
| </td> |
| </tr> |
| <tr> |
| <td>state</td> |
| <td> |
| <a href="../tapestry-framework/hivedoc/config/tapestry.state.ApplicationObjects.html"> |
| tapestry.state.ApplicationObjects |
| </a> |
| </td> |
| </tr> |
| <tr> |
| <td>validator</td> |
| <td> |
| <a href="../tapestry-framework/hivedoc/config/tapestry.valid.Validators.html"> |
| tapestry.valid.Validators |
| </a> |
| </td> |
| </tr> |
| </table> |
| |
| </section> |
| </body> |
| </document> |
