ExpressionColumn Class
- public class ExpressionColumn
extends FormattableColumn
A column that can use expressions in addition to
formatters to format the value of a data cell. The expression
column enables combining data from different fields of the current
data item or even from different expression contexts into
a value for the cell. An expression column is not sortable
or filterable.
Attribute Descriptions |
Attribute | Required | Runtime Expression Evaluation | Data Bindable |
title | No | No | No |
The text that will be rendered in the header for this column. |
value | No | No | Yes |
The expression value that can contain expressions that reference data in the
current data item. The result of the expression evaluation will be rendered in the data cell.
|
Related Topics
Grid
-
Hierarchy
-
Object
TagSupport
BodyTagSupport
AbstractBaseTag
StructuredBaseTag
GridComponent
GridColumn
FormattableColumn
ExpressionColumn
-
All Implemented Interfaces
-
BodyTag
, Formattable
, IterationTag
, Serializable
, Tag
Fields from com.bea.wlw.netui.tags.AbstractBaseTag |
ATTR_GENERAL , ATTR_GENERAL_EXPRESSION , ATTR_JAVASCRIPT , ATTR_STYLE , CLASS , ID , JAVASCRIPT_STATUS , NAME , NETUI_UNIQUE_CNT , ONCLICK , ONDBLCLICK , ONKEYDOWN , ONKEYPRESS , ONKEYUP , ONMOUSEDOWN , ONMOUSEMOVE , ONMOUSEOUT , ONMOUSEOVER , ONMOUSEUP , STYLE , TABINDEX
|
Methods from com.bea.wlw.netui.tags.databinding.grid.column.GridColumn |
getColumns , getStyleClassPrefix , getValidContainerType , localRelease , prepare , renderCloseCellTag , renderDataCellTag , renderEndTag , renderFooterCellTag , renderHeaderCellTag , renderOpenCellTag , renderStartTag , setStyleClassPrefix
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Methods from com.bea.wlw.netui.tags.databinding.base.StructuredBaseTag |
addContent, doEndTag, doStartTag, getContent, getCurrentRenderState, getValidContainerType, localRelease, prepare, renderEndTag, renderStartTag, verifyAttributes, verifyStructure |
Methods from com.bea.wlw.netui.tags.AbstractBaseTag |
addTagIdMapping , evaluateAttributeToString , filter , filter , getJavaScriptUtils , getNearestForm , getScriptReporter , getUserLocale , localRelease , registerTagError , release , renderAttribute , rewriteName , write
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Methods from javax.servlet.jsp.tagext.TagSupport |
doAfterBody, doEndTag, doStartTag, findAncestorWithClass, getId, getParent, getValue, getValues, release, removeValue, setId, setPageContext, setParent, setValue |
Methods from class java.lang.Object |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
ExpressionColumn
public ExpressionColumn()
getTagName() Method
public String
getTagName()
Get the name of this tag. This is used to identify the type of this tag
for reporting tag errors.
-
Overrides
-
AbstractBaseTag.getTagName()
Returns
- a constant String representing the name of this tag.
getTitle() Method
public String
getTitle()
Get the title rendered in the header cell of this column.
Returns
- the title of the colum
getValue() Method
public String
getValue()
Get the value of this tag.
Returns
- the value of this tag
localRelease() Method
protected void localRelease()
Reset all of the fields of this tag.
-
Overrides
-
FormattableColumn.localRelease()
renderDataCell() Method
public String
renderDataCell()
throws JspException
Render a cell for the "current" data item. The value
attribute is first evaluated as an expression, then
formatted using any contained Formatter tags, and
is finally returned to be buffered. If errors occur during
the process of expression evaluation on the value attribute,
these errors are reported in the page.
-
Overrides
-
GridColumn.renderDataCell()
Returns
- the String content that should be buffered for this tag
Exceptions
-
JspException
- if an error occurs that can not be reported in the page
renderFooterCell() Method
public String
renderFooterCell()
Render the footer. This footer contains no text.
-
Overrides
-
GridColumn.renderFooterCell()
Returns
- the emtpy string
renderHeaderCell() Method
public String
renderHeaderCell()
Render the header cell for this column. The title
attribute is rendered in the header of an ExpressionColumn.
-
Overrides
-
GridColumn.renderHeaderCell()
Returns
- the String content that should be buffered for this tag
setTitle(String) Method
public void setTitle(String
title)
Set the title rendered in the header cell of this column.
Parameters
-
title
- the title of the column
setValue(String) Method
public void setValue(String
value)
Set the value of this tag. The value may contain an
expression(s) that will be evaluated before the data for
each item in the Grid's data set is rendered. The
databinding expression container
may be used
to access the "current" data item that is being rendered. For
example, the expression container.item
accesses
the current data item.
Parameters
-
value
- the value of this tag. This attribute may
contain expression(s).