Here's a thing i've tried on a XOOPS 2.0.13.2
It's a tip of the multimenu module (Solo71) to integrate a menu directly in a theme.
tell me if i'm wrong with my response :
we must change some code in theme, but it's easy :)
i've 2 theme : "sable" and "automne"
i want to display a block "sable_only", only in "sable theme".
not in "automne theme".
here's the code change.
create a block named : sable_only
put in it, whatever you want
configure it to display in left column.
then, some changes to appply to the first theme :
edit themes/sable/theme.html
look for :
<{foreach item=block from=$xoops_lblocks}>
<{include file="sable/theme_blockleft.html"}>
<{/foreach}>
add before these 3 lines :
<{foreach item=block from=$xoops_lblocks}>
<{if $block.title == 'sable_only'}>
<{include file="sable/theme_blockleft.html"}>
<{/if}>
<{/foreach}>
and change original code to :
<{foreach item=block from=$xoops_lblocks}>
<{if $block.title != 'sable_only'}>
<{include file="sable/theme_blockleft.html"}>
<{/if}>
<{/foreach}>
these depends on wich theme you are using.
ok ?
in the first 'foreach' code, i display only the block named 'sable_only'.
in the second 'foreach', i display all blocks, except 'sable_only'.
edit the second theme's file :
themes/automne/theme.html
look for code who's displaying left column.
in my case :
<{foreach item=block from=$xoops_lblocks}>
<table cellspacing="0" cellpadding="2">
<tr>
<td class="blockTitle"> <img src="<{$xoops_url}>/themes/<{$xoops_theme}>/images/maru.gif"> <{$block.title}>td>tr>
<tr><td class="blockContent"><{$block.content}>td>tr>table>
<{/foreach}>
and change it to :
<{foreach item=block from=$xoops_lblocks}>
<{if $block.title != 'sable_only'}>
<table cellspacing="0" cellpadding="2">
<tr>
<td class="blockTitle"> <img src="<{$xoops_url}>/themes/<{$xoops_theme}>/images/maru.gif"> <{$block.title}>td>tr>
<tr><td class="blockContent"><{$block.content}>td>tr>table>
<{/if}>
<{/foreach}>
in order to display all blocks, except blocks named 'sable_only'
thus, if i'm on my website, with sable theme activated, i can see the block 'sable_only', and all others left blocks.
and if i switch theme to "automne", i can see all blocks of the left column, except the 'sable_only' block.
i hope this post responds to your question, and help you a little !
and scuse my very bad english ! :-p