To write your own layout you're gonna need few new jsp pages.
they are all situated in jbosswiki/fore-wiki/src/web/WEB-INF/jsp
There are some attributes you can (or you have to) use, to show apropriate content
What is it?
Action url passed from portlet. Use it to prepare links.
Name of the whole Wiki. Just to show header.
Content of a page to show.
Name of the showing page.
Name of the default page.
Friendly link of current page ex. http://host.domain/wiki/PageName
Link to RSS feed.
Link to RDF feed.
Link to ATOM feed.
WikiType to show.
Edit date of current page to show.
Name of the author of current page to show.
Link to images showed in Wiki (for wiki buttons, logo etc.).
If loged in user is admin.
If page is viewable by current user (only for showing info).
If page is editable by current user (only for showing info).
If user is guest or is loged in.
Wheather to show attachment upload form or not.
Number of current version.
Error message (if any) to show.
only PageInfo.jsp page to show info about (sorry - logic inside JSP).
only Edit.jsp id of current edit session (needs to be passed back while Canceling or Saving page).
For file attachmnet you have to create a form:
what is important - names and values have to have those values or file uploading won't work.
Submiting new page
Your form have to send those values:
<input type="hidden" name="editedPage" value="page name" />
<input type="hidden" name="page" value="name to show after saving current page - probably same page" />
<input type="hidden" name="editSessionId" value="edit session id (passed in attribute)" />
Be careful while creating Save/Cancel buttons. editSessionId is also mandatory.