[GRASS-dev] selection of subgroup in i.* modules

[Glynn Clements]

Moritz Lennert wrote:

> Before posting a bug report I just wanted to make sure, as I have a 
> vague memory that this has been discussed before:
> 
> Is it normal that I do not get a dropdown list of subgroups in i.* 
> modules (i.gensig, i.maxlik, i.gensigset, ...) after having selected a 
> group ?

Probably.

Subgroups aren't stand-alone entities, they're a property of a
specific group. So to get a list of subgroups, you'd need to know the
group. IOW, the GUI needs to know that the set of allowed values for a
"subgroup" option is the set of subgroups for the group specified by
some other option. But there's no way for a module to report that
relationship to the parser, so the parser can't report it to the GUI.

The GUI might be able to do a similar hack to what is done for
database columns (IIRC, "column" options are populated with the list
of columns for the most recently selected database). Although, if any
modules have the option to name a not-yet-existing subgroup, that
would have to be distinguished from existing subgroups.

> In g.gui.iclass I get the choice of subgroups after having selected
> a group.

g.gui.iclass is a GUI module, which means it gets to implement its own
GUI. The others are command-line modules which have their GUI
auto-generated from the --interface-description output.

-- 
Glynn Clements <glynn at gclements.plus.com>