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| <H2> |
| Package org.apache.struts.taglib.html |
| </H2> |
| <a name="doc.Description">The "struts-html" tag library</a> contains JSP |
| custom tags useful in creating dynamic HTML user interfaces, including input |
| forms. |
| <P> |
| <B>See: </B> |
| <BR> |
| <A HREF="#package_description"><B>Description</B></A> |
| <P> |
| |
| <TABLE BORDER="1" CELLPADDING="3" CELLSPACING="0" WIDTH="100%"> |
| <TR BGCOLOR="#CCCCFF" CLASS="TableHeadingColor"> |
| <TD COLSPAN=2><FONT SIZE="+2"> |
| <B>Class Summary</B></FONT></TD> |
| </TR> |
| <TR BGCOLOR="white" CLASS="TableRowColor"> |
| <TD WIDTH="15%"><B><A HREF="BaseFieldTag.html">BaseFieldTag</A></B></TD> |
| <TD>Convenience base class for the various input tags for text fields.</TD> |
| </TR> |
| <TR BGCOLOR="white" CLASS="TableRowColor"> |
| <TD WIDTH="15%"><B><A HREF="BaseHandlerTag.html">BaseHandlerTag</A></B></TD> |
| <TD>Base class for tags that render form elements capable of including JavaScript |
| event handlers and/or CSS Style attributes.</TD> |
| </TR> |
| <TR BGCOLOR="white" CLASS="TableRowColor"> |
| <TD WIDTH="15%"><B><A HREF="BaseInputTag.html">BaseInputTag</A></B></TD> |
| <TD>Abstract base class for the various input tags.</TD> |
| </TR> |
| <TR BGCOLOR="white" CLASS="TableRowColor"> |
| <TD WIDTH="15%"><B><A HREF="BaseTag.html">BaseTag</A></B></TD> |
| <TD>Renders an HTML <base> element with an href |
| attribute pointing to the absolute location of the enclosing JSP page.</TD> |
| </TR> |
| <TR BGCOLOR="white" CLASS="TableRowColor"> |
| <TD WIDTH="15%"><B><A HREF="ButtonTag.html">ButtonTag</A></B></TD> |
| <TD>Renders an HTML BUTTON tag within the Struts framework.</TD> |
| </TR> |
| <TR BGCOLOR="white" CLASS="TableRowColor"> |
| <TD WIDTH="15%"><B><A HREF="CancelTag.html">CancelTag</A></B></TD> |
| <TD>Tag for input fields of type "cancel".</TD> |
| </TR> |
| <TR BGCOLOR="white" CLASS="TableRowColor"> |
| <TD WIDTH="15%"><B><A HREF="CheckboxTag.html">CheckboxTag</A></B></TD> |
| <TD>Tag for input fields of type "checkbox".</TD> |
| </TR> |
| <TR BGCOLOR="white" CLASS="TableRowColor"> |
| <TD WIDTH="15%"><B><A HREF="Constants.html">Constants</A></B></TD> |
| <TD>Manifest constants for this package.</TD> |
| </TR> |
| <TR BGCOLOR="white" CLASS="TableRowColor"> |
| <TD WIDTH="15%"><B><A HREF="ErrorsTag.html">ErrorsTag</A></B></TD> |
| <TD>Custom tag that renders error messages if an appropriate request attribute |
| has been created.</TD> |
| </TR> |
| <TR BGCOLOR="white" CLASS="TableRowColor"> |
| <TD WIDTH="15%"><B><A HREF="FileTag.html">FileTag</A></B></TD> |
| <TD>Custom tag for input fields of type "file".</TD> |
| </TR> |
| <TR BGCOLOR="white" CLASS="TableRowColor"> |
| <TD WIDTH="15%"><B><A HREF="FormTag.html">FormTag</A></B></TD> |
| <TD>Custom tag that represents an input form, associated with a bean whose |
| properties correspond to the various fields of the form.</TD> |
| </TR> |
| <TR BGCOLOR="white" CLASS="TableRowColor"> |
| <TD WIDTH="15%"><B><A HREF="HiddenTag.html">HiddenTag</A></B></TD> |
| <TD>Custom tag for input fields of type "text".</TD> |
| </TR> |
| <TR BGCOLOR="white" CLASS="TableRowColor"> |
| <TD WIDTH="15%"><B><A HREF="HtmlTag.html">HtmlTag</A></B></TD> |
| <TD>Renders an HTML <html> element with appropriate language attributes if |
| there is a current Locale available in the user's session.</TD> |
| </TR> |
| <TR BGCOLOR="white" CLASS="TableRowColor"> |
| <TD WIDTH="15%"><B><A HREF="ImageTag.html">ImageTag</A></B></TD> |
| <TD>Tag for input fields of type "image".</TD> |
| </TR> |
| <TR BGCOLOR="white" CLASS="TableRowColor"> |
| <TD WIDTH="15%"><B><A HREF="ImgTag.html">ImgTag</A></B></TD> |
| <TD>Generate an IMG tag to the specified image URI.</TD> |
| </TR> |
| <TR BGCOLOR="white" CLASS="TableRowColor"> |
| <TD WIDTH="15%"><B><A HREF="LinkTag.html">LinkTag</A></B></TD> |
| <TD>Generate a URL-encoded hyperlink to the specified URI.</TD> |
| </TR> |
| <TR BGCOLOR="white" CLASS="TableRowColor"> |
| <TD WIDTH="15%"><B><A HREF="MultiboxTag.html">MultiboxTag</A></B></TD> |
| <TD>Tag for input fields of type "checkbox".</TD> |
| </TR> |
| <TR BGCOLOR="white" CLASS="TableRowColor"> |
| <TD WIDTH="15%"><B><A HREF="OptionsTag.html">OptionsTag</A></B></TD> |
| <TD>Tag for creating multiple <select> options from a collection.</TD> |
| </TR> |
| <TR BGCOLOR="white" CLASS="TableRowColor"> |
| <TD WIDTH="15%"><B><A HREF="OptionTag.html">OptionTag</A></B></TD> |
| <TD>Tag for select options.</TD> |
| </TR> |
| <TR BGCOLOR="white" CLASS="TableRowColor"> |
| <TD WIDTH="15%"><B><A HREF="PasswordTag.html">PasswordTag</A></B></TD> |
| <TD>Custom tag for input fields of type "text".</TD> |
| </TR> |
| <TR BGCOLOR="white" CLASS="TableRowColor"> |
| <TD WIDTH="15%"><B><A HREF="RadioTag.html">RadioTag</A></B></TD> |
| <TD>Tag for input fields of type "radio".</TD> |
| </TR> |
| <TR BGCOLOR="white" CLASS="TableRowColor"> |
| <TD WIDTH="15%"><B><A HREF="ResetTag.html">ResetTag</A></B></TD> |
| <TD>Tag for input fields of type "reset".</TD> |
| </TR> |
| <TR BGCOLOR="white" CLASS="TableRowColor"> |
| <TD WIDTH="15%"><B><A HREF="RewriteTag.html">RewriteTag</A></B></TD> |
| <TD>Generate a URL-encoded URI as a string.</TD> |
| </TR> |
| <TR BGCOLOR="white" CLASS="TableRowColor"> |
| <TD WIDTH="15%"><B><A HREF="SelectTag.html">SelectTag</A></B></TD> |
| <TD>Custom tag that represents an HTML select element, associated with a |
| bean property specified by our attributes.</TD> |
| </TR> |
| <TR BGCOLOR="white" CLASS="TableRowColor"> |
| <TD WIDTH="15%"><B><A HREF="SubmitTag.html">SubmitTag</A></B></TD> |
| <TD>Tag for input fields of type "submit".</TD> |
| </TR> |
| <TR BGCOLOR="white" CLASS="TableRowColor"> |
| <TD WIDTH="15%"><B><A HREF="TextareaTag.html">TextareaTag</A></B></TD> |
| <TD>Custom tag for input fields of type "textarea".</TD> |
| </TR> |
| <TR BGCOLOR="white" CLASS="TableRowColor"> |
| <TD WIDTH="15%"><B><A HREF="TextTag.html">TextTag</A></B></TD> |
| <TD>Custom tag for input fields of type "text".</TD> |
| </TR> |
| </TABLE> |
| |
| |
| <P> |
| <A NAME="package_description"><!-- --></A><H2> |
| Package org.apache.struts.taglib.html Description |
| </H2> |
| |
| <P> |
| <p><a name="doc.Description">The "struts-html" tag library</a> contains JSP |
| custom tags useful in creating dynamic HTML user interfaces, including input |
| forms.</p> |
| <div align="center"> |
| <p> <a href="#doc.Intro">[Introduction]</a> <a href="#doc.Form">[HTML Form Tags]</a> |
| <a href="#doc.Other">[Other HTML Tags]</a> </p> |
| </div> |
| |
| <hr> |
| |
| <h3><a name="doc.Intro">Introduction</a></h3> |
| |
| <p>The tags in the Struts HTML library form a bridge between a JSP view and the |
| other components of a Web application. Since a dynamic Web application often |
| depends on gathering data from a user, input forms play an important role in |
| the Struts framework. Consequently, the majority of the HTML tags involve <a href="#doc.Form">HTML</a> |
| forms. Other important issues addressed by the Struts-HTML tags are <a href="#doc.Other.errors">error |
| messages</a>, <a href="#doc.Other.hyperlinking">hyperlinking</a> and <a href="#doc.Other.i18n">internationalization</a>.</p> |
| |
| <hr> |
| <h3><a name="doc.Form">HTML "form" tags</a></h3> |
| |
| <ul> |
| <li><a href="../../../../../../struts-html.html#button">button</a></li> |
| <li><a href="../../../../../../struts-html.html#cancel">cancel</a></li> |
| <li><a href="../../../../../../struts-html.html#checkbox">checkboxes</a></li> |
| <li><a href="../../../../../../struts-html.html#file">file</a></li> |
| <li><a href="../../../../../../struts-html.html#hidden">hidden</a></li> |
| <li><a href="../../../../../../struts-html.html#image">image</a></li> |
| <li><a href="../../../../../../struts-html.html#multibox">multibox</a></li> |
| <li><a href="../../../../../../struts-html.html#password">password</a> input fields</li> |
| <li><a href="../../../../../../struts-html.html#radio">radio</a> buttons</li> |
| <li><a href="../../../../../../struts-html.html#reset">reset</a> buttons</li> |
| <li><a href="../../../../../../struts-html.html#select">select</a> lists with embedded</li> |
| <li><a href="../../../../../../struts-html.html#option">option</a></li> |
| <li><a href="../../../../../../struts-html.html#options">options</a></li> |
| <li><a href="../../../../../../struts-html.html#submit">submit</a> buttons</li> |
| <li><a href="../../../../../../struts-html.html#text">text</a> input fields</li> |
| <li><a href="../../../../../../struts-html.html#textarea">textareas</a></li> |
| </ul> |
| |
| <p>Each of these tags must be nested within a <html:form> tag.</p> |
| |
| <h4><a name="doc.Form.formTag">About the form tag</a></h4> |
| |
| <p>The Struts <code>form</code> tag outputs a standard HTML form tag, and also |
| links the input form with a JavaBean subclassed from the Struts ActionForm object |
| (see <a href="../../../../../../api/index.html">Javadoc</a>). Each field in |
| the form should correspond to a property of the form's bean. When a field and |
| property correspond, the bean is first used to populate the form, and then to |
| store the user's input when the form is submitted to the controller servlet.</p> |
| |
| <p>The name of the bean and its class can be specified as a property to the form tag, but |
| may also be omitted. If omitted, the <code>ActionMappings</code> database (loaded from the |
| <code>struts-config.xml</code> file) is consulted. If the current page is specified as |
| the <code>input</code> property for an <code>action</code>, the name of the |
| <code>action</code> is used. The <code>type</code> property for the bean is also then taken |
| from the configuration, via a Form Bean definition.</p> |
| |
| <p>Here's a clip from the Struts Example configuration:</p> |
| |
| <pre> |
| <action-mappings> |
| <!-- Process a user logon --> |
| <action path="/logon" |
| type="org.apache.struts.example.LogonAction" |
| name="logonForm" |
| scope="request" |
| input="/logon.jsp"> |
| </action> |
| < ... /> |
| </action-mappings> |
| <form-beans> |
| <!-- Logon form bean --> |
| <form-bean name="logonForm" |
| type="org.apache.struts.example.LogonForm"/> |
| < ... /> |
| </form-beans> |
| </pre> |
| </pre> |
| |
| <p>Given this configuration, the HTML form tag for <code>logon.jsp</code> will default |
| to using "<code>logonForm</code>" as its name property and |
| "<code>org.apache.struts.example.LogonForm</code>" as the attribute's type. This way you |
| can manage the namespace for your framework components from the configuration file.</p> |
| |
| <p>If the form tag does not find the form bean in any of the scopes (page, request, |
| session, application), it creates one using the specified type.</p> |
| |
| <p>The Struts <code>ActionForm</code> class is equipped with standard <code>reset()</code> |
| and <code>validate()</code> methods, that can be used by the controller to enable |
| automatic data validation. See the <a href="../../../../../../userGuide/building_view.html#form_validation"> |
| Users Guide</a> for more about Form Validation. An important aspect of validation |
| is reporting errors to the user. This can be handled by the Struts <code>errors</code> |
| tag, which is discussed <a href="#doc.Other.errors">later in this document</a>.</p> |
| |
| <hr> |
| <h4><a name="doc.Form.attributes">Common Form Tag Attributes</a></h4> |
| |
| <p>The form "field" tags in the Struts-HTML tag library share a common set of |
| tag attributes that have the same meaning, no matter what field tag they are |
| used with. These properties also accept Runtime Expressions, meaning you can |
| set them with a scriptlet. The common attributes fall into four categories: |
| <a href="#doc.Form.attributes.struts">Struts Common,</a> <a href="#doc.Form.attributes.navigation">HTML |
| Navigation</a>, <a href="#doc.Form.attributes.javascript">Javascript</a>, and |
| <a href="#doc.Form.attributes.css">CSS</a>.</p> |
| <h5><a name="doc.Form.attributes.struts">Struts Common</a></h5> |
| <div align="center"> |
| <center> |
| <table width=90% border="1" cellpadding="4"> |
| <tr> |
| <td> name </td> |
| <td> The attribute name of the <code>ActionForm</code> bean whose properties |
| are consulted when rendering the current value of this input field. |
| If not specified, the bean associated with the form tag we are nested |
| within is utilized. </td> |
| </tr> |
| <tr> |
| <td> property </td> |
| <td> Name of the request parameter that will be included with this submission, |
| set to the specified value. </td> |
| </tr> |
| <tr> |
| <td> value </td> |
| <td> Value of the label to be used with this element. This value will |
| also be submitted as the value of the specified request parameter. [Body |
| of this tag (if any), or "Click"] </td> |
| </tr> |
| </table> |
| </center> |
| </div> |
| <p> </p> |
| <p>Like <a href="../bean/package-summary.html#doc.Properties">Struts-Bean</a> |
| tags, the property attribute for the Struts-HTML tags accept simple, nested, |
| and indexed expressions. For example, this tag:</p> |
| <pre> |
| <html:text property="mailingAddress.street"/> |
| </pre> |
| <p>corresponds to:</p> |
| <pre> |
| getMailingAddress().getStreet() |
| </pre> |
| <p>For more about using simple, nested, and indexed expressions with Struts, see |
| the <a href="../bean/package-summary.html#doc.Properties">Struts-Bean Developers |
| Guide.</a> </p> |
| <h5><a name="doc.Form.attributes.javascript">Javascript Event Handlers</a></h5> |
| <div align="center"> |
| <center> |
| <table width=90% border="1" cellpadding="4"> |
| <tr> |
| <td> onblur </td> |
| <td> Executed when this element loses input focus. </td> |
| </tr> |
| <tr> |
| <td> onchange </td> |
| <td> Executed when this element loses input focus and its value has changed. |
| </td> |
| </tr> |
| <tr> |
| <td> onclick </td> |
| <td> Executed when this element receives a mouse click. </td> |
| </tr> |
| <tr> |
| <td> ondblclick </td> |
| <td> Executed when this element receives a mouse - double click. </td> |
| </tr> |
| <tr> |
| <td> onfocus </td> |
| <td> Executed when this element receives input focus. </td> |
| </tr> |
| <tr> |
| <td> onkeydown </td> |
| <td> Executed when this element has focus and a key is depressed. |
| </td> |
| </tr> |
| <tr> |
| <td> onkeypress </td> |
| <td> Executed when this element has focus and a key is depressed and released |
| </td> |
| </tr> |
| <tr> |
| <td> onkeyup </td> |
| <td> Executed when this element has focus and a key is released </td> |
| </tr> |
| <tr> |
| <td> onmousedown </td> |
| <td> Executed when this element is under the mouse pointer and a mouse |
| button is depressed. </td> |
| </tr> |
| <tr> |
| <td> onmousemove </td> |
| <td> Executed when this element is under the mouse pointer and the pointer |
| is moved. </td> |
| </tr> |
| <tr> |
| <td> onmouseout </td> |
| <td> Executed when this element was under the mouse pointer but the pointer |
| was moved outside the element. </td> |
| </tr> |
| <tr> |
| <td> onmouseover </td> |
| <td> Executed when this element was not under the mouse pointer but the |
| pointer is moved inside the element. </td> |
| </tr> |
| <tr> |
| <td> onmouseup </td> |
| <td> Executed when this element is under the mouse pointer and a mouse |
| button is released. </td> |
| </tr> |
| <tr> |
| <td> </td> |
| <td> <b>"parent" form tag only</b> </td> |
| </tr> |
| <tr> |
| <td> onreset </td> |
| <td> Executed if the form is reset. </td> |
| </tr> |
| <tr> |
| <td> onsubmit </td> |
| <td> Executed if the form is submitted. </td> |
| </tr> |
| </table> |
| </center> |
| </div> |
| <h5> </h5> |
| <h5><a name="doc.Form.attributes.navigation">HTML Navigation Attributes</a></h5> |
| <div align="center"> |
| <center> |
| <table width=90% border="1" cellpadding="4"> |
| <tr> |
| <td> accesskey </td> |
| <td> The keyboard character used to move focus immediately to this element. |
| </td> |
| </tr> |
| <tr> |
| <td> tabindex </td> |
| <td> The tab order (ascending positive integers) for this element. </td> |
| </tr> |
| </table> |
| </center> |
| </div> |
| <h5> </h5> |
| <h5><a name="doc.Form.attributes.css">CSS Attributes</a></h5> |
| <div align="center"> |
| <center> |
| <table width=90% border="1" cellpadding="4"> |
| <tr> |
| <td> style </td> |
| <td> CSS styles to be applied to this HTML element. </td> |
| </tr> |
| <tr> |
| <td> styleClass </td> |
| <td> CSS stylesheet class to be applied to this HTML element. </td> |
| </tr> |
| </table> |
| </center> |
| </div> |
| <p> </p> |
| <p>See the <a href="../../../../../../struts-html.html">HTML Tags Reference</a> |
| for detailed information about the available tags in this tag library, and the |
| complete list of valid attributes for each tag.</p> |
| <hr> |
| <h3><a name="doc.Other">Other HTML tags</a></h3> |
| <p>Aside from form processing, the Struts-HTML offers several other tags or tag |
| properties to help with displaying error messages, maintaining hyperlinks, and |
| with internationalizing your application.</p> |
| <h4><a name="doc.Other.errors">Displaying Error Messages</a></h4> |
| <p>Error handling is an important part of any application, and curing an error |
| often involves getting the user's help. Struts provides a generalized method |
| for communicating runtime messages to users, based on the same technology used |
| to provide internationalization. </p> |
| <p>In a Web application, it is common to reuse the input page to display error |
| messages. The Struts error message tag can be placed wherever you would like |
| the messages to display. If no messages are pending, nothing is printed.</p> |
| <p>By default, the errors tag will print all pending messages. You can also specify |
| a property when queuing a message, and then refer to that property in the errors |
| tag. In that case, only the message for that property will be displayed. This |
| is helpful when you would like to place the message for a field next to the |
| actual field.</p> |
| <p>Error messages are often queued in the ActionForm validate method. Here's a |
| snippet from the Struts Example application:</p> |
| <pre> ActionErrors errors = new ActionErrors(); |
| if ((username == null) || (username.length() < 1)) |
| errors.add("username", new ActionError("error.username.required")); |
| if ((password == null) || (password.length() < 1)) |
| errors.add("password", |
| new ActionError("error.password.required")); |
| </pre> |
| <p>This queues two error messages, one for the "username" field and another for |
| the "password" field. To print all the messages together, simply place the error |
| tag anywhere in your JSP.</p> |
| <pre> |
| <body bgcolor="white"> |
| <html:errors/> |
| </pre> |
| <p>Or, you can place specific error messages at different locations</p> |
| <pre> |
| <td align="left"> |
| <html:text property="username" size="16" maxlength="16"/> |
| <html:errors property="username"/> |
| </td> |
| </tr><tr> |
| <td align="left"> |
| <html:text property="password" size="16" maxlength="16"/> |
| <html:errors property="password"/> |
| </td> |
| </pre> |
| <p>By default, the actual error message is retrieved from the application's standard |
| message resource. This gives you a master list of the error messages used by |
| your application, and provides for internationalization. In the code snippet, |
| the message corresponding to "error.username.required" would be retrieved and |
| displayed to the user at runtime. </p> |
| <pre> |
| error.username.required=<li>Username is required</li> |
| </pre> |
| <p>Most often, error messages are displayed in a particular way. To make it easy |
| to format your messages, you can also specific an <code>errors.header</code> |
| and <code>errors.footer</code> string in your message resource. Typically, you |
| might want to render the messages in a different color, or set them up |
| to appear in an unordered list. Using the <code>errors.header</code> and <code>errors.footer</code> |
| strings keeps the setup codes out of your JSP until a message actually prints.</p> |
| <pre> |
| errors.header=<h3><font color="red">Validation Error</font></h3> |
| You must correct the following error(s) before proceeding:<UL> |
| errors.footer=</ul><hr> |
| </pre> |
| <h4><a name="doc.Other.hyperlinking">Maintaining Hyperlinks</a></h4> |
| <ul> |
| <li><a href="../../../../../../struts-html.html#base">base</a></li> |
| </ul> |
| <p>When implementing a Web application, it is usually a good idea to use relative |
| references to other files in the same application. But in a dynamic application, |
| the controller servlet often returns a completely different file than the one |
| requested. (Often, the requested "file" doesn't actually exist, but represents |
| an action for the controller to interpret.) Since relative references are resolved |
| by the browser, they often won't work in a dynamic application.</p> |
| <p>To accommodate this, the Struts-HTML taglib provides a <code><base></code> |
| tag that renders an HTML |
| <base> |
| element with an href attribute pointing to the absolute location of its page. |
| </p> |
| <p>As a rule, you should place the Struts-HTML base tag in the <head> section |
| of any JSP that uses relative references to other files.</p> |
| <pre> |
| <head> |
| <html:base/> |
| </head> |
| </pre> |
| <h4><a name="doc.Other.sessions">Session Tracking</a></h4> |
| <p>The Java Servlet framework has built-in support for tracking a client through |
| a session. Sessions are a useful way to compensate for the stateless nature |
| of HTTP. Tracking a client can be done with either cookies or URL rewriting, |
| cookies being preferred when available. Struts offers three tags that make it |
| easy to write "session-aware" hyperlink references:</p> |
| <ul> |
| <li><a href="../../../../../../struts-html.html#link">link</a> - Renders an |
| HTML anchor or hyperlink.</li> |
| <li><a href="../../../../../../struts-html.html#rewrite">rewrite</a> - Renders |
| a request URI, but without creating the <a> hyperlink. This tag is useful |
| when you want to generate a string constant for use by a JavaScript procedure.</li> |
| <li><a href="../../../../../../struts-html.html#img">img</a> - Renders an HTML |
| <img> element with the image at the specified URL.</li> |
| </ul> |
| <p>Each of these tags will automatically apply URL rewriting, to maintain session |
| state in the absence of cookies. The content displayed for the hyperlink will |
| be taken from the body of the tag. The base URL for the hyperlink is calculated |
| based on properties given with the tag.</p> |
| <p>Normally, the hyperlink or URI you specify is left unchanged. If you would |
| like to include dynamic parameters to the hyperlink or URI, you can pass those |
| to the tags via a JavaBean. If there may be naming conflicts, you can also specify |
| the scope that the tag searches (request, page, session, application). </p> |
| <p>To pass a single dynamic parameter, specify the parameter's name using the |
| <code>paramId</code> attribute. You can then specify the name of the JavaBean |
| holding the value using the <code>paramName</code> attribute, and a particular |
| property using <code>paramProperty</code>. </p> |
| <p>So, a tag like</p> |
| <pre> <html:link paramId="target" |
| paramName="linkParams" <br> paramProperty="target" |
| paramScope="request"<br> >detail.html</html:link></pre> |
| <p>would correspond to something like</p> |
| <pre> <A HREF="detail.html?<%= <br> request.getParameter("linkParams").getTarget() |
| %>"></A> |
| </pre> |
| <p>To search all scopes (request, page, session, and application), omit <code>paramScope</code>. |
| </p> |
| <p>The <code>paramProperty</code> attribute may also be omitted, so long as the |
| named bean identifies a value that can be converted to a String. |
| <p>To pass multiple dynamic parameters, you can store them in a <code><a href="http://java.sun.com/j2se/1.3/docs/api/java/util/Map.html">java.util.Map</a></code>, |
| and use the name of the map for the <code>paramName</code>. The map must then |
| contain one or more <code>paramIds</code> and their corresponding values. As |
| the Map is processed, the keys are assumed to be the names of query parameters |
| to be appended. The value associated with each key must be either a String or |
| a String array representing the parameter value(s). If a String array is specified, |
| more than one value for the same query parameter name will be created. |
| <p>The HTML session tracking tags use several common attributes, that can be organized |
| into three groups, as follows. All of these attributes are not used by all three |
| tags (<code>link</code>, <code>rewrite</code>, and <code>img</code>), and so |
| the tags using each attribute is given. |
| <p> |
| <table width=90% border="1" cellpadding="4"> |
| <tr> |
| <th colspan="2">forward, href, and page</th> |
| </tr> |
| <tr> |
| <td> forward </td> |
| <td> [ link rewrite ] - Logical name of a global ActionForward that contains |
| the actual content-relative URI of the destination of this transfer. This |
| hyperlink may be dynamically modified by the inclusion of query parameters, |
| as described in the tag description. You must specify exactly one of the |
| forward attribute, the href attribute, the linkName attribute, or the page |
| attribute </td> |
| </tr> |
| <tr> |
| <td> href </td> |
| <td> [ link rewrite ] - The URL to which this hyperlink will transfer control |
| if activated. This hyperlink may be dynamically modified by the inclusion |
| of query parameters, as described in the tag description. You must specify |
| exactly one of the forward attribute, the href attribute, the linkName attribute, |
| or the page attribute. </td> |
| </tr> |
| <tr> |
| <td> page </td> |
| <td> [ link rewrite ] - The context-relative path, starting with a slash, |
| of the image to be displayed by this tag. The rendered URL for this image |
| will automatically prepend the context path of this web application (in |
| the same manner as the page attribute on the link tag works), in addition |
| to any necessary URL rewriting. You must specify either the page attribute |
| or the src attribute. </td> |
| </tr> |
| </table> |
| <p> |
| <table width=90% border="1" cellpadding="4"> |
| <tr> |
| <th colspan="2">linkName, Target , and src</th> |
| </tr> |
| <tr> |
| <td> linkName </td> |
| <td> |
| <p>[ link ] - The anchor name to be defined within this page, so that you |
| can reference it with intra-page hyperlinks. In other words, the value |
| specified here will render a "name" element in the generated anchor tag. |
| </p> |
| </td> |
| </tr> |
| <tr> |
| <td> target </td> |
| <td> [ link img ] - The window target in which the resource requested by this |
| hyperlink will be displayed, for example in a framed presentation. </td> |
| </tr> |
| <tr> |
| <td> src </td> |
| <td> [ img ] - The URL to which this image will be transferred from This image |
| may be dynamically modified by the inclusion of query parameters, as described |
| in the tag description. This value will be used unmodified (other than potential |
| URL rewriting) as the value of the "src" attribute in the rendered tag. |
| You must specify either the page attribute or the the src attribute. </td> |
| </tr> |
| </table> |
| <p> |
| <table width=90% border="1" cellpadding="4"> |
| <tr> |
| <th colspan="2">paramId, paramName, paramProperty, paramScope </th> |
| </tr> |
| <tr> |
| <td> paramId </td> |
| <td> [ link img ] - The name of the request parameter that will be dynamically |
| added to the generated src URL. The corresponding value is defined by the |
| paramName and (optional) paramProperty attributes, optionally scoped by |
| the paramScope attribute</td> |
| </tr> |
| <tr> |
| <td> paramName </td> |
| <td> [ link img ] - The name of a JSP bean that is a String containing the |
| value for the request parameter named by paramId (if paramProperty is not |
| specified), or a JSP bean whose property getter is called to return a String |
| (if paramProperty is specified). The JSP bean is constrained to the bean |
| scope specified by the paramScope property, if it is specified. </td> |
| </tr> |
| <tr> |
| <td> paramProperty </td> |
| <td> [ link img ] - The name of a property of the bean specified by the paramName |
| attribute, whose return value must be a String containing the value of the |
| request parameter (named by the paramId attribute) that will be dynamically |
| added to this hyperlink or src URL</td> |
| </tr> |
| <tr> |
| <td> paramScope </td> |
| <td> [ link img ] - The scope within which to search for the bean specified |
| by the paramName attribute. If not specified, all scopes are searched. </td> |
| </tr> |
| </table> |
| <p> |
| <table width=90% border="1" cellpadding="4"> |
| <tr> |
| <th colspan="2"> |
| <p>name, property, scope |
| </th> |
| </tr> |
| <tr> |
| <td> name </td> |
| <td> [ link rewrite img ] - The name of a JSP bean that contains a <code><a href="http://java.sun.com/j2se/1.3/docs/api/java/util/Map.html">Map</a></code> |
| representing the query parameters (if <code>property</code> is not specified), |
| or a JSP bean whose property getter is called to return a <code>Map</code> |
| (if <code>property</code> is specified). </td> |
| </tr> |
| <tr> |
| <td> property </td> |
| <td>[ link rewrite img ] - The name of a property of the bean specified by |
| the name attribute, whose return value must be a <code><a href="http://java.sun.com/j2se/1.3/docs/api/java/util/Map.html">Map</a></code> |
| containing the query parameters to be added to the src URL. You <b>must</b> |
| specify the name attribute if you specify this attribute </td> |
| </tr> |
| <tr> |
| <td> scope </td> |
| <td> [ link rewrite img ] - The scope within which to search for the bean |
| specified by the name attribute. If not specified, all scopes are searched. |
| </td> |
| </tr> |
| </table> |
| <p>See the <a href="../../../../../../struts-html.html">HTML Tags Reference</a> |
| for the complete list of valid attributes for each tag.. |
| <h4><a name="doc.Other.i18n">Internationalization</a></h4> |
| <p>Internationalization is automatically supported by the HTML tags where appropriate. |
| </p> |
| <p><a href="../../../../../../struts-html.html#errors">Errors</a> - By default, |
| the text for your messages will be returned by the default message resource, |
| which will select the appropriate language for the user. You may also specify |
| another message resource using the <code>bundle</code> attribute.</p> |
| <p><a href="../../../../../../struts-html.html#html">HTML</a> - Renders an HTML |
| element with language attributes extracted from the user's current Locale object, |
| if there is one. </p> |
| <p><a href="../../../../../../struts-html.html#image">image</a> and <a href="../../../../../../struts-html.html#img">img</a> |
| - Can optionally retrieve the value for its binary source and alt text from |
| the message resource, so that different images and/or text can be provided for |
| different locales. See the tag's <code>altKey</code>, <code>srcKey</code>, and |
| <code>bundle</code> attributes in the <a href="../../../../../../struts-html.html">HTML |
| Tags Reference</a>.</p> |
| <p>See the <a href="../../../../../../userGuide/building_view.html#i18n">Users |
| Guide</a> for more on how Struts helps you internationalize your applications.</p> |
| <p> </p> |
| <P> |
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