Specifying a layout using (X)HTML

Table2GridBag expects the layout to be specified as an (X)HTML table. It does not matter whether the input file contains just a table definition or a complete HTML document (in the later case, all tags except TABLE, TR and TD are silently ignored). Nevertheless, some constraints apply:

  • When a complete HTML document is given, it must be well formed.
  • The input file must contain exactly one table definition. Nesting within each other tables is not allowed.
  • At least one table cell must have a width and a height attribute. Otherwise, the resulting layout code will clump all components together in one place.
  • Table cells may span rows or columns as long as they remain rectangular. Cells may not overlap each other or have gaps in between them.
  • Cells must only contain the name of the component, they are referring to. The name may be surrounded by whitespace.
  • Cells may be left "empty" by immediately closing the TD tag or by only putting spaces in them to indicate that this cell should automatically be populated by a filler component.

Attributes of the TABLE tag

border
The border attribute is ignored by Table2GridBag, but should be given anyway, so the table shows properly in a web browser.
cellpadding
Global value for GridBagConstraints.ipadx and code>GridBagConstraints.ipady field.
cellspacing
Global default value for GridBagConstraints.insets (same on all four sides). This can be overridden individually for each table cell.

The use of attributes other than border is discouraged.

Attributes of the TR tag

The table row tag does not support any attributes.

Attributes of the TD tag

rowspan
Value for the GridBagConstraints.gridwidth field. The default value is "1".
colspan
Value for the GridBagConstraints.gridheight field. The default value is "1".
width
Value for the GridBagConstraints.weigthx field. The default value is "0". At least one cell must specify a non zero value for this attribute. Values must be specified in percent.
height
Value for the GridBagConstraints.weigthy field. The default value is "0". At least one cell must specify a non zero value for this attribute. Values must be specified in percent.
align
Specifies the horizontal anchor alignment. The use of this attribute is deprecated. Use the style attribute instead.
valign
Specifies the vertical anchor alignment. The use of this attribute is deprecated. Use the style attribute instead.
style
This attribute allows for the individual styling of the component. The aspects that can be styled are the anchor position, the way the component expands and it's insets. By default, components are centered, stretch in both directions and have a zero pixel padding. This is equivalent to giving the style as:

style="fill:both ; anchor:center ; insets:0,0,0,0"

The value of the style attribute is case insensitive, parameters may be given in any order (or not be present at all) and can be separated from each other by any amount of white space (including none).

The optional CAPTION tag

You may use the HTML caption tag to give the table a caption. When you do, that tag must contain a fully qualified class name and table2gridbag will automatically produce a complete Java class by that name. Example:

<table>
  <caption>de.onyxbits.Layout</caption>
  <tr>
    <td width="100%" height="100%">myComponent</td>
  </tr>
</table>

The caption can always be overridden on the commandline via the -Dclass= argument.