TikiWiki has had an admin interface to display site identity options flexibly, but in previous releases these items were generally just added in a vertical stack, since there wasn't any particular "top" to the page.
But for themes that have a specific area for site identity items, stacking won't work. Instead, the items must be placed side-by-side. This page describes the method being used to place these items, which include the logo, banner ad, search form, log-in form Look & Feel options, and the div that holds custom code data.
Following the logic of the tiki-site_header.tpl template file, this is how items are displayed:
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Custom code with and without a banner ad
(if custom code is used) (if there is an ad banner) <div id="sitead" class="floatright"> (Banner is displayed here.) </div> <div id="customcodewith_ad"> (Here will be parsed the 400px-wide custom site header code.} </div>
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(else) <div id="customcode"> (Full-width custom code area here.) </div> (/if)
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(else)
...Look & Feel options with no custom code:
Displaying a logo, with or without an ad banner
(if there is a logo and the logo left or right) <div class="clearfix" id="sioptions"> (if logo is at left) (if there is an ad) <div id="sitead" class="floatright"> (Ad goes here.) </div> (/if) <div id="sitelogo" class="floatleft"> (Logo goes here.) </div> (/if)
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(if logo is at right) {if there is an ad) <div id="sitead" class="floatleft"> (Ad goes here.) </div> (/if) <div id="sitelogo" class="floatright"> (Logo goes here.) </div> (/if) </div> (/if)
Logo centered, and there is an ad: to work in small vertical space, the ad (halfbanner) is floated left; a second banner zone is floated right
(if logo and logo is centered} <div class="clearfix" id="sioptionscentered"> (if there is an ad banner) <div id="bannertopright" class="floatright"> ( ad goes here.) </div> <div id="sitead" class="floatleft"> (Ad goes here.) </div> (/if) <div id="sitelogo"> (Logo goes here.) </div> </div> (/if)
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No logo but there is an ad, so ad is centered.
(if no logo) (if there is an ad) <div style="text-align:center"> (Ad goes here.) </div> (/if) (/if)
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(/if)
Finally, tiki-site_header.tpl has code for the login form:
(if site header login) (Site header log-in form goes here.) (/if) (/if}
This is the method used for new themes including Darkroom, Feb12, The News, and Tikinewt, in Branch 2.0, and for themes listed on http://themes.tikiwiki.org/Themes_for_TW2. There are variations in some cases due to theme-specific space configurations, etc.
Very possibly this code could be improved, and I'd welcome that.