[Chameleon] Legend template/xml structure

[Ken Sanderson]

Hello all. Now that I have chameleon up and functioning, as well as
created a map file using Maplab I wanted to jump into doing some
modifications to my legend.

I have a layer with multiple class objects that I also want to show up
in the legend. Basically it's a polygon layer that is displayed by an
attribute value. Displays well, but the legend just displays the top
color rather then each of the potential attribute colors.

So I have been looking at the legendtemplate widget, along with the
legend_template.html file, and further the sample_themes.xml file,
trying to decide whats the best way to go about this and I have a few
questions.

Is there any documentation on the scripting in the legend_template.html
file, such as variables, what opt_flag is for and what other options you
have there, what is the isset operator, etc? Same for the xml page, is
there a schema for it? If I wanted to include classes is there a <class>
object? Can you put a <group> within a <group>?

Thanks,

Ken