Author: lukaszlenart
Date: Thu Jul 10 06:19:57 2014
New Revision: 915641
Log:
Updates production
Modified:
websites/production/struts/content/release/2.3.x/docs/struts-control-tags.html
Modified:
websites/production/struts/content/release/2.3.x/docs/struts-control-tags.html
==============================================================================
---
websites/production/struts/content/release/2.3.x/docs/struts-control-tags.html
(original)
+++
websites/production/struts/content/release/2.3.x/docs/struts-control-tags.html
Thu Jul 10 06:19:57 2014
@@ -37,6 +37,7 @@ under the License.
<link href='http://struts.apache.org/highlighter/style/shCoreStruts.css'
rel='stylesheet' type='text/css' />
<link href='http://struts.apache.org/highlighter/style/shThemeStruts.css'
rel='stylesheet' type='text/css' />
<script src='http://struts.apache.org/highlighter/js/shCore.js'
type='text/javascript'></script>
+ <script src='http://struts.apache.org/highlighter/js/shBrushXml.js'
type='text/javascript'></script>
<script src='http://struts.apache.org/highlighter/js/shBrushJava.js'
type='text/javascript'></script>
<script type="text/javascript">
@@ -146,61 +147,35 @@ under the License.
<p>The <a shape="rect" class="external-link"
href="http://struts.apache.org/mail.html";>Struts 2 user mailing list</a> is an
excellent place to get help. If you are having a problem getting the tutorial
example applications to work search the Struts 2 mailing list. If you don't
find an answer to your problem, post a question on the mailing list.</p>
</div>
</div>
-<h3 id="StrutsControlTags-Struts2ifTag">Struts 2 if Tag</h3><p>In the example
application's thankyou.jsp is this markup.</p><div class="code panel pdl"
style="border-width: 1px;"><div class="codeContent panelContent pdl">
-<script class="theme: Default; brush: html; gutter: false"
type="syntaxhighlighter"><![CDATA[<s:if
test="personBean.over21">
-
+<h3 id="StrutsControlTags-Struts2ifTag">Struts 2 if Tag</h3><p>In the example
application's thankyou.jsp is this markup.</p><div class="code panel pdl"
style="border-width: 1px;"><div class="codeHeader panelHeader pdl"
style="border-bottom-width: 1px;"><b>thankyou.jsp Struts if Tag</b></div><div
class="codeContent panelContent pdl">
+<script class="theme: Default; brush: xml; gutter: false"
type="syntaxhighlighter"><![CDATA[<s:if
test="personBean.over21">
<p>You are old enough to vote!</p>
-
</s:if>
-
<s:else>
-
<p>You are NOT old enough to vote.</p>
-
</s:else>
-
]]></script>
</div></div><p>The Struts if tag has a test attribute. The value of the test
attribute must evaluate to true or false. If true the statements between the
opening and closing s:if tags will be executed. If false, the statements
between the opening and closing s:else tags will be executed. Note that s:else
tags come after the closing s:if tag and that the s:else tags are not
required.</p><p>In the above example the Struts framework will call method
getPersonBean exposed by the Action class (EditAction.java). Using the Person
object returned by that method, the framework will then call method isOver21 of
class Person. That method returns a boolean that will be used to determine if
the test is true or false.</p><p>The value of the test attribute must be an
expression that evaluates to true or false, but doesn't need to be a method
call that returns a boolean. For example this s:if tag that is in thankyou.jsp
has a more complicated expression.</p><div class="code panel pdl" style="border
-width: 1px;"><div class="codeContent panelContent pdl">
-<script class="theme: Default; brush: html; gutter: false"
type="syntaxhighlighter"><![CDATA[<s:if
test="personBean.carModels.length > 1">
-
+<script class="theme: Default; brush: xml; gutter: false"
type="syntaxhighlighter"><![CDATA[<s:if
test="personBean.carModels.length > 1">
<p>Car models
-
</s:if>
-
<s:else>
-
<p>Car model
-
-
</s:else>
-
-
]]></script>
</div></div><p>The purpose of the above markup is to use either "Car model" or
"Car models" depending on how many car models the user selected on the edit
page. So the value for the test attribute of this iterator tag gets the length
of the carModels String array and compares that to 1. If it's greater then 1,
the correct grammar is "Car models" else the correct grammar is "Car
model".</p><h3 id="StrutsControlTags-StrutsiteratorTag">Struts iterator
Tag</h3><p>The Struts iterator tag is used to generate a loop that iterates
over each item in a collection. In the thankyou.jsp is this markup.</p><div
class="code panel pdl" style="border-width: 1px;"><div class="codeContent
panelContent pdl">
<script class="theme: Default; brush: html; gutter: false"
type="syntaxhighlighter"><![CDATA[<table
style="margin-left:15px">
-
<s:iterator value="personBean.carModels">
-
<tr><td><s:property /></td></tr>
-
</s:iterator>
-
</table>
-
-
]]></script>
</div></div><p>The goal of this code is to create an HTML table with a row
that display a car model selected by the user on the edit page. The car models
the user selects on the edit page are stored in the carModels field (a String
array) of the personBean object (of class Person).</p><p>The iterator tag has a
value attribute that must evaluate to a collection (Array, List,
Map).</p><p>The s:property tag nested inside the iterator tag is used to
display the specific value of the collection each time the iterator loops over
an element of the collection. Since the collection is an Array of String
objects, the s:property tag doesn't need to specify a value attribute. By
default the s:property tag will display the single String for that element of
the collection.</p><p>If the collection contains objects that have multiple
fields, then you should use the value attribute of the s:property tag to
determine what field to display. For example:</p><div class="code panel pdl"
style="border-wid
th: 1px;"><div class="codeContent panelContent pdl">
-<script class="theme: Default; brush: html; gutter: false"
type="syntaxhighlighter"><![CDATA[<table
style="margin-left:15px">
-
- <s:iterator value="states" >
-
+<script class="theme: Default; brush: xml; gutter: false"
type="syntaxhighlighter"><![CDATA[<table
style="margin-left:15px">
+ <s:iterator value="states" >
<tr><td><s:property value="stateAbbr"
/></td> <td><s:property value="stateName"
/></tr>
-
</s:iterator>
-
</table>
-
-
]]></script>
</div></div><p>The value of the iterator tag is states, which causes the
Struts 2 framework to call the getStates method of the Action class
(EditAction.java). The getStates method returns a List of State objects. The
State class has two fields stateAbbr and stateName, both having the appropriate
get method. The iterator will loop over each State object stored in the
collection. Each time through the loop, the Struts 2 framework will have a
reference to the current State object and will call getStateAbbr and
getStateName methods for that current State object.</p><h3
id="StrutsControlTags-AdditionalIteratorAttributes">Additional Iterator
Attributes</h3><p>The Struts 2 iterator tag has additional attributes you can
use to control the begin and end values for specifying that the iterator tag
should only loop over a part of the collection. See the <a shape="rect"
href="https://cwiki.apache.org/confluence/display/WW/iterator";>iterator tag
reference</a> for more information.</p></div>
</div>
