uidata.html

j2ee帮助文档软件设计/软件工程 文件格式

</DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>header</CODE> - the new header facet
<DT><B>Throws:</B>
<DD><CODE><A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/NullPointerException.html" title="class or interface in java.lang">NullPointerException</A></CODE> - if <code>header</code> is
   <code>null</code></DL>
</DD>
</DL>
<HR>

<A NAME="isRowAvailable()"><!-- --></A><H3>
isRowAvailable</H3>
<PRE>
public boolean <B>isRowAvailable</B>()</PRE>
<DL>
<DD><p>Return a flag indicating whether there is <code>rowData</code>
 available at the current <code>rowIndex</code>.  If no
 <code>wrappedData</code> is available, return <code>false</code>.</p>
<P>
<DD><DL>
</DL>
</DD>
<DD><DL>

<DT><B>Throws:</B>
<DD><CODE><A HREF="../../../javax/faces/FacesException.html" title="class in javax.faces">FacesException</A></CODE> - if an error occurs getting the row availability</DL>
</DD>
</DL>
<HR>

<A NAME="getRowCount()"><!-- --></A><H3>
getRowCount</H3>
<PRE>
public int <B>getRowCount</B>()</PRE>
<DL>
<DD><p>Return the number of rows in the underlying data model.  If the
 number of available rows is unknown, return -1.</p>
<P>
<DD><DL>
</DL>
</DD>
<DD><DL>

<DT><B>Throws:</B>
<DD><CODE><A HREF="../../../javax/faces/FacesException.html" title="class in javax.faces">FacesException</A></CODE> - if an error occurs getting the row count</DL>
</DD>
</DL>
<HR>

<A NAME="getRowData()"><!-- --></A><H3>
getRowData</H3>
<PRE>
public <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html" title="class or interface in java.lang">Object</A> <B>getRowData</B>()</PRE>
<DL>
<DD><p>Return the data object representing the data for the currently
 selected row index, if any.</p>
<P>
<DD><DL>
</DL>
</DD>
<DD><DL>

<DT><B>Throws:</B>
<DD><CODE><A HREF="../../../javax/faces/FacesException.html" title="class in javax.faces">FacesException</A></CODE> - if an error occurs getting the row data
<DD><CODE><A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/IllegalArgumentException.html" title="class or interface in java.lang">IllegalArgumentException</A></CODE> - if now row data is available
  at the currently specified row index</DL>
</DD>
</DL>
<HR>

<A NAME="getRowIndex()"><!-- --></A><H3>
getRowIndex</H3>
<PRE>
public int <B>getRowIndex</B>()</PRE>
<DL>
<DD><p>Return the zero-relative index of the currently selected row.  If
 we are not currently positioned on a row, return -1.  This property
 is <strong>not</strong> enabled for value binding expressions.</p>
<P>
<DD><DL>
</DL>
</DD>
<DD><DL>

<DT><B>Throws:</B>
<DD><CODE><A HREF="../../../javax/faces/FacesException.html" title="class in javax.faces">FacesException</A></CODE> - if an error occurs getting the row index</DL>
</DD>
</DL>
<HR>

<A NAME="setRowIndex(int)"><!-- --></A><H3>
setRowIndex</H3>
<PRE>
public void <B>setRowIndex</B>(int&nbsp;rowIndex)</PRE>
<DL>
<DD><p>Set the zero relative index of the current row, or -1 to indicate that
 no row is currently selected, by implementing the following algorithm.
 It is possible to set the row index at a value for which the underlying
 data collection does not contain any row data.  Therefore, callers may
 use the <code>isRowAvailable()</code> method to detect whether row data
 will be available for use by the <code>getRowData()</code> method.</p>
</p>
 <ul>
 <li>Save current state information for all descendant components (as
     described below).
 <li>Store the new row index, and pass it on to the <A HREF="../../../javax/faces/model/DataModel.html" title="class in javax.faces.model"><CODE>DataModel</CODE></A>
     associated with this <A HREF="../../../javax/faces/component/UIData.html" title="class in javax.faces.component"><CODE>UIData</CODE></A> instance.</li>
 <li>If the new <code>rowIndex</code> value is -1:
     <ul>
     <li>If the <code>var</code> property is not null,
         remove the corresponding request scope attribute (if any).</li>
     <li>Reset the state information for all descendant components
         (as described below).</li>
     </ul></li>
 <li>If the new <code>rowIndex</code> value is not -1:
     <ul>
     <li>If the <code>var</code> property is not null, call
         <code>getRowData()</code> and expose the resulting data object
         as a request scope attribute whose key is the <code>var</code>
         property value.</li>
     <li>Reset the state information for all descendant components
         (as described below).
     </ul></li>
 </ul>

 <p>To save current state information for all descendant components,
 <A HREF="../../../javax/faces/component/UIData.html" title="class in javax.faces.component"><CODE>UIData</CODE></A> must maintain per-row information for each descendant
 as follows:<p>
 <ul>
 <li>If the descendant is an instance of <code>EditableValueHolder</code>, save
     the state of its <code>localValue</code> property.</li>
 <li>If the descendant is an instance of <code>EditableValueHolder</code>,
     save the state of the <code>localValueSet</code> property.</li>
 <li>If the descendant is an instance of <code>EditableValueHolder</code>, save
     the state of the <code>valid</code> property.</li>
 <li>If the descendant is an instance of <code>EditableValueHolder</code>,
     save the state of the <code>submittedValue</code> property.</li>
 </ul>

 <p>To restore current state information for all descendant components,
 <A HREF="../../../javax/faces/component/UIData.html" title="class in javax.faces.component"><CODE>UIData</CODE></A> must reference its previously stored information for the
 current <code>rowIndex</code> and call setters for each descendant
 as follows:</p>
 <ul>
 <li>If the descendant is an instance of <code>EditableValueHolder</code>,
     restore the <code>value</code> property.</li>
 <li>If the descendant is an instance of <code>EditableValueHolder</code>,
     restore the state of the <code>localValueSet</code> property.</li>
 <li>If the descendant is an instance of <code>EditableValueHolder</code>,
     restore the state of the <code>valid</code> property.</li>
 <li>If the descendant is an instance of <code>EditableValueHolder</code>,
     restore the state of the <code>submittedValue</code> property.</li>
 </ul>
<P>
<DD><DL>
</DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>rowIndex</CODE> - The new row index value, or -1 for no associated row
<DT><B>Throws:</B>
<DD><CODE><A HREF="../../../javax/faces/FacesException.html" title="class in javax.faces">FacesException</A></CODE> - if an error occurs setting the row index
<DD><CODE><A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/IllegalArgumentException.html" title="class or interface in java.lang">IllegalArgumentException</A></CODE> - if <code>rowIndex</code>
  is less than -1</DL>
</DD>
</DL>
<HR>

<A NAME="getRows()"><!-- --></A><H3>
getRows</H3>
<PRE>
public int <B>getRows</B>()</PRE>
<DL>
<DD><p>Return the number of rows to be displayed, or zero for all
 remaining rows in the table.  The default value of this
 property is zero.</p>
<P>
<DD><DL>
</DL>
</DD>
<DD><DL>
</DL>
</DD>
</DL>
<HR>

<A NAME="setRows(int)"><!-- --></A><H3>
setRows</H3>
<PRE>
public void <B>setRows</B>(int&nbsp;rows)</PRE>
<DL>
<DD><p>Set the number of rows to be displayed, or zero for all
 remaining rows in the table.</p>
<P>
<DD><DL>
</DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>rows</CODE> - New number of rows
<DT><B>Throws:</B>
<DD><CODE><A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/IllegalArgumentException.html" title="class or interface in java.lang">IllegalArgumentException</A></CODE> - if <code>rows</code>
  is negative</DL>
</DD>
</DL>
<HR>

<A NAME="getVar()"><!-- --></A><H3>
getVar</H3>
<PRE>
public <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/String.html" title="class or interface in java.lang">String</A> <B>getVar</B>()</PRE>
<DL>
<DD><p>Return the request-scope attribute under which the data object
 for the current row will be exposed when iterating.  This property
 is <strong>not</strong> enabled for value binding expressions.</p>
<P>
<DD><DL>
</DL>
</DD>
<DD><DL>
</DL>
</DD>
</DL>
<HR>

<A NAME="setVar(java.lang.String)"><!-- --></A><H3>
setVar</H3>
<PRE>
public void <B>setVar</B>(<A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/String.html" title="class or interface in java.lang">String</A>&nbsp;var)</PRE>
<DL>
<DD><p>Set the request-scope attribute under which the data object
 for the current row wil be exposed when iterating.</p>
<P>
<DD><DL>