Chapter 24. Seam JSF controls - JBoss Seam 1.2.1 正式版英文参考手册

Chapter 24. Seam JSF controls
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Chapter 24. Seam JSF controls

Seam includes a number of JSF controls that are useful for working with Seam. These are intended to complement the built-in JSF controls, and controls from other third-party libraries. We recommend the Ajax4JSF and ADF faces (now Trinidad) tag libraries for use with Seam. We do not recommend the use of the Tomahawk tag library.

To use these controls, define the "s" namespace in your page as follows (facelets only):

<html xmlns="http://www.w3.org/1999/xhtml"
      xmlns:s="http://jboss.com/products/seam/taglib">

The ui example demonstrates the use of a number of these tags.

Table 24.1. Seam JSF Control Reference

`<s:validate>`	Description A non-visual control, validates a JSF input field against the bound property using Hibernate Validator. Attributes None. Usage <h:inputText id="userName" required="true" value="#{customer.userName}"> <s:validate /> </h:inputText> <h:message for="userName" styleClass="error" />
`<s:validateAll>`	Description A non-visual control, validates all child JSF input fields against their bound properties using Hibernate Validator. Attributes None. Usage <s:validateAll> <div class="entry"> <h:outputLabel for="username">Username:</h:outputLabel> <h:inputText id="username" value="#{user.username}" required="true"/> <h:message for="username" styleClass="error" /> </div> <div class="entry"> <h:outputLabel for="password">Password:</h:outputLabel> <h:inputSecret id="password" value="#{user.password}" required="true"/> <h:message for="password" styleClass="error" /> </div> <div class="entry"> <h:outputLabel for="verify">Verify Password:</h:outputLabel> <h:inputSecret id="verify" value="#{register.verify}" required="true"/> <h:message for="verify" styleClass="error" /> </div> </s:validateAll>
`<s:formattedText>`	Description Outputs Seam Text, a rich text markup useful for blogs, wikis and other applications that might use rich text. See the Seam Text chapter for full usage. Attributes `value` — an EL expression specifying the rich text markup to render. Usage <s:formattedText value="#{blog.text}"/> Example
`<s:convertDateTime>`	Description Perform date or time conversions in the Seam timezone. Attributes None. Usage
`<s:convertEnum>`	Description Assigns an enum converter to the current component. This is primarily useful for radio button and dropdown controls. Attributes None. Usage
`<s:convertEntity>`	Description Assigns an entity converter to the current component. This is primarily useful for radio button and dropdown controls. The converter works with any entity which has an `@Id` annotation - either simple or composite. If your Managed Persistence Context isn't called `entityManager`, then you need to set it in components.xml: Attributes None. Configuration <component name="org.jboss.seam.ui.entityConverter"> <property name="entityManager">#{em}</property> </component> Usage <h:selectOneMenu value="#{person.continent}" required="true"> <s:selectItems value="#{continents.resultList}" var="continent" label="#{continent.name}" noSelectionLabel="Please Select..."/> <s:convertEntity /> </h:selectOneMenu>
`<s:enumItem>`	Description Creates a `SelectItem` from an enum value. Attributes `enumValue` — the string representation of the enum value. `label` — the label to be used when rendering the `SelectItem`. Usage
`<s:selectItems>`	Description Creates a `List<SelectItem>` from a List, Set, DataModel or Array. Attributes `value` — an EL expression specifying the data that backs the `List<SelectItem>` `var` — defines the name of the local variable that holds the current object during iteration `label` — the label to be used when rendering the `SelectItem`. Can reference the `var` variable `disabled` — if true the `SelectItem` will be rendered disabled. Can reference the `var` variable `noSelectionLabel` — specifies the (optional) label to place at the top of list (if `required="true"` is also specified then selecting this value will cause a validation error) `hideNoSelectionLabel` — if true, the `noSelectionLabel` will be hidden when a value is selected Usage <h:selectOneMenu value="#{person.age}" converter="#{converters.ageConverter}"> <s:selectItems value="#{ages}" var="age" label="#{age}" /> </h:selectOneMenu>
`<s:graphicImage>`	Description An extended `<h:graphicImage>` that allows the image to be created in a Seam Component; further transforms can be applied to the image. Facelets only. All attributes for `<h:graphicImage>` are supported, as well as: Attributes `value` — image to display. Can be a path `String` (loaded from the classpath), a `byte[]`, a `java.io.File`, a `java.io.InputStream` or a `java.net.URL`. Currently supported image formats are `image/png`, `image/jpeg` and `image/gif`. `fileName` — if not specified the served image will have a generated file name. If you want to name your file, you should specify it here. This name should be unique Transformations To apply a transform to the image, you would nest a tag specifying the transform to apply. Seam currently supports these transforms: `<s:transformImageSize>` `width` — new width of the image `height` — new height of the image `maintainRatio` — if `true`, and one of `width`/`height` are specified, the image will be resized with the dimension not specified being calculated to maintain the aspect ratio. `factor` — scale the image by the given factor `<s:transformImageBlur>` `radius` — perform a convolution blur with the given radius `<s:transformImageType>` `contentType` — alter the type of the image to either `image/jpeg` or `image/png` It's easy to create your own transform - create a `UIComponent` which `implements` `org.jboss.seam.ui.graphicImage.ImageTransform`. Inside the `applyTransform()`method use `image.getBufferedImage()` to get the original image and `image.setBufferedImage()` to set your transformed image. Transforms are applied in the order specified in the view. Usage
`<s:decorate>`	Description "Decorate" a JSF input field when validation fails or when `required="true"` is set. Attributes None. Usage
`<s:layoutForm>`	Description A layout component for producing a "standard" form layout. Each child component will be treated as a row, and if the child is a `<s:decorate>`, additional formatting will be applied: Label — if a `label` facet is on the `<s:decorate>` then it's contents will be used as the label for this field. The labels are rendered right-aligned in a column Some further decoration facets are supported - `beforeLabel`, `afterLabel`, `aroundLabel`, `beforeInvalidLabel`, `afterInvalidLabel` and `aroundInvalidLabel`. Other text — if a `belowLabel` facet or/and a `belowField` facet are present on `<s:decorate>` then it's contents will be placed below the label or the field Required — if `required="true"` is set on the field, then the `aroundRequiredField`, `beforeRequiredField`, `afterRequiredField`, `aroundRequiredLabel`, `beforeRequiredLabel` and `afterRequiredLabel` will be applied. Attributes None. Usage <s:layoutForm> <f:facet name="aroundInvalidField"> <s:span styleClass="error"/> </f:facet> <f:facet name="afterInvalidField"> <s:message /> </f:facet> <f:facet name="beforeRequiredLabel"> <s:span>&lowast;</s:span> </f:facet> <f:facet name="aroundLabel"> <s:span style="text-align:right;" /> </f:facet> <f:facet name="aroundInvalidLabel"> <s:span style="text-align:right;" styleClass="error" /> </f:facet> <s:decorate> <f:facet name="label"> <h:outputText value="Name" /> </f:facet> <h:inputText value="#{person.name}" required="true"/> <f:facet name="belowField"> <h:outputText styleClass="help" value="Enter your name as it appears on your passport" /> </f:facet> </s:decorate> </s:layoutForm>
`<s:message>`	Description "Decorate" a JSF input field with the validation error message. Attributes None. Usage
`<s:span>`	Description Render a HTML `<span>`. Attributes None. Usage
`<s:div>`	Description Render a HTML `<div>`. Attributes None. Usage
`<s:fragment>`	Description A non-rendering component useful for enabling/disabling rendering of it's children. Attributes None. Usage
`<s:cache>`	Description Cache the rendered page fragment using JBoss Cache. Note that `<s:cache>` actually uses the instance of JBoss Cache managed by the built-in `pojoCache` component. Attributes `key` — the key to cache rendered content, often a value expression. For example, if we were caching a page fragment that displays a document, we might use `key="Document-#{document.id}"`. `enabled` — a value expression that determines if the cache should be used. `region` — a JBoss Cache node to use (different nodes can have different expiry policies). Usage
`<s:link>`	Description A link that supports invocation of an action with control over conversation propagation. Does not submit the form. Attributes `value` — the label. `action` — a method binding that specified the action listener. `view` — the JSF view id to link to. `fragment` — the fragment identifier to link to. `disabled` — is the link disabled? `propagation` — determines the conversation propagation style: `begin`, `join`, `nest`, `none` or `end`. `pageflow` — a pageflow definition to begin. (This is only useful when `propagation="begin"` or `propagation="join"`.) Usage
`<s:button>`	Description A button that supports invocation of an action with control over conversation propagation. Does not submit the form. Attributes `value` — the label. `action` — a method binding that specified the action listener. `view` — the JSF view id to link to. `fragment` — the fragment identifier to link to. `disabled` — is the link disabled? `propagation` — determines the conversation propagation style: `begin`, `join`, `nest`, `none` or `end`. `pageflow` — a pageflow definition to begin. (This is only useful when `propagation="begin"` or `propagation="join"`.) Usage
`<s:selectDate>`	Description Displays a dynamic date picker component that selects a date for the specified input field. The body of the `selectDate` element should contain HTML elements, such as text or an image, that prompt the user to click to display the date picker. The date picker must be styled using CSS. An example CSS file can be found in the Seam booking demo as `date.css`, or can be generated using seam-gen. The CSS styles used to control the appearance of the date picker are also described below. Attributes `for` — The id of the input field that the date picker will insert the selected date into. `dateFormat` — The date format string. This should match the date format of the input field. `startYear` — The popup year selector range will start at this year. `endYear` — The popup year selector range will end at this year. Usage <div class="row"> <h:outputLabel for="dob">Date of birth<em></em></h:outputLabel> <h:inputText id="dob" value="#{user.dob}" required="true"> <s:convertDateTime pattern="MM/dd/yyyy"/> </h:inputText> <s:selectDate for="dob" startYear="1910" endYear="2007"><img src="img/datepicker.png"/></s:selectDate> <div class="validationError"><h:message for="dob"/></div> </div> Example* CSS Styling The following list describes the CSS class names that are used to control the style of the selectDate control. `seam-date` — This class is applied to the outer `div` containing the popup calendar. (1) It is also applied to the `table` that controls the inner layout of the calendar. (2) `seam-date-header` — This class is applied to the calendar header table row (`tr`) and header table cells (`td`). (3) `seam-date-header-prevMonth` — This class is applied to the "previous month" table cell, (`td`), which when clicked causes the calendar to display the month prior to the one currently displayed. (4) `seam-date-header-nextMonth` — This class is applied to the "next month" table cell, (`td`), which when clicked causes the calendar to display the month following the one currently displayed. (5) `seam-date-headerDays` — This class is applied to the calendar days header row (`tr`), which contains the names of the week days. (6) `seam-date-footer` — This class is applied to the calendar footer row (`tr`), which displays the current date. (7) `seam-date-inMonth` — This class is applied to the table cell (`td`) elements that contain a date within the month currently displayed. (8) `seam-date-outMonth` — This class is applied to the table cell (`td`) elements that contain a date outside of the month currently displayed. (9) `seam-date-selected` — This class is applied to the table cell (`td`) element that contains the currently selected date. (10) `seam-date-dayOff-inMonth` — This class is applied to the table cell (`td`) elements that contain a "day off" date (i.e. weekend days, Saturday and Sunday) within the currently selected month. (11) `seam-date-dayOff-outMonth` — This class is applied to the table cell (`td`) elements that contain a "day off" date (i.e. weekend days, Saturday and Sunday) outside of the currently selected month. (12) `seam-date-hover` — This class is applied to the table cell (`td`) element over which the cursor is hovering. (13) `seam-date-monthNames` — This class is applied to the `div` control that contains the popup month selector. (14) `seam-date-monthNameLink` — This class is applied to the anchor (`a`) controls that contain the popup month names. (15) `seam-date-years` — This class is applied to the `div` control that contains the popup year selector. (16) `seam-date-yearLink` — This class is applied to the anchor (`a`) controls that contain the popup years. (15)
`<s:conversationPropagation>`	Description Customize the conversation propagation for a command link or button (or similar JSF control). Facelets only. Attributes `propagation` — determines the conversation propagation style: `begin`, `join`, `nest`, `none` or `end`. `pageflow` — a pageflow definition to begin. (This is only useful when `propagation="begin"` or `propagation="join"`.) Usage
`<s:conversationId>`	Description Add the conversation id to an output link (or similar JSF control). Facelets only. Attributes None. Usage
`<s:taskId>`	Description Add the task id to an output link (or similar JSF control), when the task is available via `#{task}`. Facelets only. Attributes None. Usage
`<s:fileUpload>`	Description Renders a file upload control. This control must be used within a form with an encoding type of `multipart/form-data`, i.e: <h:form enctype="multipart/form-data"> For multipart requests, the Seam Multipart servlet filter must also be configured in `web.xml`: <filter> <filter-name>Seam Filter</filter-name> <filter-class>org.jboss.seam.web.SeamFilter</filter-class> </filter> <filter-mapping> <filter-name>Seam Filter</filter-name> <url-pattern>/</url-pattern> </filter-mapping> Configuration* The following configuration options for multipart requests may be configured in components.xml: `createTempFiles` — if this option is set to true, uploaded files are streamed to a temporary file instead of in memory. `maxRequestSize` — the maximum size of a file upload request, in bytes. Here's an example: <component class="org.jboss.seam.web.MultipartFilter"> <property name="createTempFiles">true</property> <property name="maxRequestSize">1000000</property> </component> Attributes `data` — this value binding receives the binary file data. The receiving field should be declared as a `byte[]` or `InputStream` (required). `contentType` — this value binding receives the file's content type (optional). `fileName` — this value binding receives the filename (optional). `accept` — a comma-separated list of content types to accept, may not be supported by the browser. E.g. `"images/png,images/jpg"`, `"images/"`. `style` — The control's style `styleClass` — The control's style class Usage*

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