# com.bea.wlw.netui.tags.databinding.grid.column
ImageColumn Class

public class ImageColumn
extends `SortFilterColumn`

A column that renders an image in HTML into each data cell in a column. The image that is rendered is specified with the `src` attribute and can be further parameterized with attributes to constrain its width, height, alternate text, and border. If the height and width attributes are not specified, the image is rendered at its actual size.

Required resources:

The JavaScript file `_grid.js` must be included in any JSP page with a grid that uses a filter-enabled ImageColumn. The Page Flow Wizard adds the `_grid.js` file to a project's /resources/grid directory, when you build a page flow over a database control. The JSP should contain: <script language="javascript" src="/resources/grid/_grid.js" type="text/javascript"></script>

Attribute Descriptions
Attribute | Required | Runtime Expression Evaluation | Data Bindable
--- | --- | --- | ---
alt | No | Yes | No
The alternate text displayed in the browser if the image cannot be displayed.
border | No | Yes | No
The number of pixels to display in a border around this image. The default border is zero.
height | No | Yes | Yes
The height of the image. If you omit the height and width attributes, the graphic's actual size will be used.
src | Yes | Yes | Yes
The source of the image to display.
width | No | Yes | Yes
The width of the image. If you omit the height and width attributes, the graphic's actual size will be used.

Related Topics

BinaryFlow Sample
``Grid``

Hierarchy
  `Object`
  `TagSupport`
  `BodyTagSupport`
  `AbstractBaseTag`
  `StructuredBaseTag`
  `GridComponent`
  `GridColumn`
  `FormattableColumn`
  `SortFilterColumn`
  `ImageColumn`

All Implemented Interfaces
  `BodyTag`, `Formattable`, `IterationTag`, `Serializable`, `Tag`

Direct Known Subclasses
  `AnchorColumn`

## Field Summary

Fields from com.bea.wlw.netui.tags.databinding.base`.`StructuredBaseTag``
`EMPTY_STRING`

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``

Fields from javax.servlet.jsp.tagext`.`BodyTagSupport``
`bodyContent`

Fields from javax.servlet.jsp.tagext`.`TagSupport``
`id, pageContext`

Fields from interface javax.servlet.jsp.tagext`.`BodyTag``
`EVAL_BODY_BUFFERED, EVAL_BODY_TAG`

Fields from interface javax.servlet.jsp.tagext`.`IterationTag``
`EVAL_BODY_AGAIN`

Fields from interface javax.servlet.jsp.tagext`.`Tag``
`EVAL_BODY_INCLUDE, EVAL_PAGE, SKIP_BODY, SKIP_PAGE`

## Constructor Summary

ImageColumn()

## Method Summary

`public `String`` | `getAlt`() Get the alternate text for the image.
`public int` | `getBorder`() Get the width in pixels of the border to draw around the image.
`public `String`` | `getHeight`() Get the height of the image.
`public `String`` | `getSrc`() Get the source of the image to display.
`public `String`` | `getTagName`() Get the name of this tag.
`public `String`` | `getWidth`() Get the width of the image.
`protected void` | `localRelease`() Reset all of the fields of this tag.
`protected void` | `prepare`() Perform initialization for this tag.
`public `String`` | `renderDataCell`() Render the contents of this GridColumn for each dataset item into each cell in the column.
`public `String`` | `renderFooterCell`() Render the footer.
`protected `String`` | `renderImage`()
`protected int` | `renderStartTag`(int gridState) This tag only evaluates its body when the grid is rendering its `ROWS`.
`public void` | `setAlt`(`String` alt) Set the alternate text displayed in the browser if the image can't be displayed.
`public void` | `setBorder`(int border) Set an int representing the width of the border to draw around the image.
`public void` | `setHeight`(`String` height) Set the height of the image to be displayed in pixels.
`public void` | `setSrc`(`String` src) Set the source of the image to display.
`public void` | `setWidth`(`String` width) Set the width of the image to be displayed in pixels.
`protected void` | `verifyAttributes`() Ensure that the attributes set on the tag are valid.

Methods from `com.bea.wlw.netui.tags.databinding.grid.column.`SortFilterColumn``
``canFilter`, `canSort`, `computeFilterAction`, `computeSortAction`, `getFilterAction`, `getName`, `getSortAction`, `getTitle`, `getTitleText`, `isFilterable`, `isSortable`, `renderHeaderCell`, `setFilterable`, `setFilterAction`, `setName`, `setSortable`, `setSortAction`, `setTitle`,`

Methods from `com.bea.wlw.netui.tags.databinding.grid.column.`FormattableColumn``
``addFormatter`, `format`, `localRelease`,`

Methods from `com.bea.wlw.netui.tags.databinding.grid.column.`GridColumn``
``getColumns`, `getStyleClassPrefix`, `getValidContainerType`, `localRelease`, `prepare`, `renderCloseCellTag`, `renderDataCellTag`, `renderEndTag`, `renderFooterCellTag`, `renderHeaderCell`, `renderHeaderCellTag`, `renderOpenCellTag`, `renderStartTag`, `setStyleClassPrefix``

Methods from `com.bea.wlw.netui.tags.databinding.grid.`GridComponent``
``getCurrentRenderState`, `getGrid`, `getGridContext`, `getValidContainerType`, `localRelease`, `prepare``

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``

Methods from `javax.servlet.jsp.tagext.`BodyTagSupport``
`doAfterBody, doEndTag, doInitBody, doStartTag, getBodyContent, getPreviousOut, release, setBodyContent`

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`

Methods from interface `javax.servlet.jsp.tagext.`BodyTag``
`doInitBody, setBodyContent`

Methods from interface `com.bea.wlw.netui.tags.html.`Formattable``
``addFormatter``

Methods from interface `javax.servlet.jsp.tagext.`IterationTag``
`doAfterBody`

Methods from interface `javax.servlet.jsp.tagext.`Tag``
`doEndTag, doStartTag, getParent, release, setPageContext, setParent`

## Constructor Detail

### ImageColumn

    public ImageColumn()

## Method Detail

### getAlt() Method

    public String getAlt()

Get the alternate text for the image.

#### Returns

the alternate text

### getBorder() Method

    public int getBorder()

Get the width in pixels of the border to draw around the image.

#### Returns

the pixel width int; the default is zero.

### getHeight() Method

    public String getHeight()

Get the height of the image.

#### Returns

the fixed height of the image

### getSrc() Method

    public String getSrc()

Get the source of the image to display.

#### Returns

the source of an image

### 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.

### getWidth() Method

    public String getWidth()

Get the width of the image.

#### Returns

the fixed width of the image

### localRelease() Method

    protected void localRelease()

Reset all of the fields of this tag.

Overrides
  `SortFilterColumn.localRelease()`

### prepare() Method

    protected void prepare()

Perform initialization for this tag.

Overrides
  `SortFilterColumn.prepare()`

### renderDataCell() Method

    public String renderDataCell()
         throws JspException

Description copied from `GridColumn.renderDataCell()`
Render the contents of this GridColumn for each dataset item into each cell in the column.

Overrides
  `GridColumn.renderDataCell()`

#### Exceptions

``JspException``
  if an error occurred 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

### renderImage() Method

    protected String renderImage()
         throws JspException

#### Exceptions

``JspException``

### renderStartTag(int) Method

    protected int renderStartTag(int gridState)

This tag only evaluates its body when the grid is rendering its `ROWS`.

Overrides
  `FormattableColumn.renderStartTag(int)`

#### Parameters

gridState
  the state of this column's Grid tag parent

#### Returns

EVAL_BODY_BUFFERED

### setAlt(String) Method

    public void setAlt(String alt)

Set the alternate text displayed in the browser if the image can't be displayed.

#### Parameters

alt
  the alternate text

### setBorder(int) Method

    public void setBorder(int border)

Set an int representing the width of the border to draw around the image.

#### Parameters

border
  boolean for image border drawing

### setHeight(String) Method

    public void setHeight(String height)

Set the height of the image to be displayed in pixels.

#### Parameters

height
  the fixed height of the image

### setSrc(String) Method

    public void setSrc(String src)

Set the source of the image to display.

#### Parameters

src
  the source of an image

### setWidth(String) Method

    public void setWidth(String width)

Set the width of the image to be displayed in pixels.

#### Parameters

width
  the fixed width of the image

### verifyAttributes() Method

    protected void verifyAttributes()
         throws JspException

Description copied from `SortFilterColumn.verifyAttributes()`
Ensure that the attributes set on the tag are valid. The requirements are:

- If the column is determined to be filterable using the `SortFilterColumn.canFilter()``` method, the `SortFilterColumn.computeFilterAction()``` must return an action.
- If the column is determined to be sortable using the `SortFilterColumn.canSort()``` method, the `SortFilterColumn.computeSortAction()``` must return an action.

Overrides
  `SortFilterColumn.verifyAttributes()`

#### Exceptions

``JspException``
  if an error occurs that can not be reported in the page