I just want to know the path which I can change the code to add a wallpaper with the extralite theme for example.
If you look at the extralite theme.html, you will see reference URLs like:
These point to files relative to the module code, or (particularly for you) the theme jar. In a theme MBean descriptor, you will see:
When this theme MBean is deployed, /themes/ is mapped to where the Root attribute points to in the nukes classpath.
I succeed on setting a wallpaper but the center content still have a blank wallpaper.
There is a fix in CVS for the extralite theme about this. The comment on the fix is:
Themes based on ThemeTemplate can define 'middle' sections, not 'centre' sections. Previously, if blocks were put into Side=1/center, they would not be displayed by this theme.
<!-- BEGIN centre -->
<!-- END centre -->
<!-- BEGIN middle -->
<!-- END middle -->
Actually the problem is just the section where the selected module is displayed;e.g : the forum,the news...
it seems that this is a module section independent from the selected theme and must be configured separately.