<td>)</td>
<td></td>
<td></td>
<td width="100%"> </td>
</tr></table>
</div>
<div class="memdoc"><p>Centers <b>widget</b> on the desktop, taking multi-head setups into
account. If <b>screen</b> is -1, <b>widget</b> will be centered on its
current screen (if it was shown already) or on the primary screen.
If <b>screen</b> is -3, <b>widget</b> will be centered on the screen that
currently contains the mouse pointer.
<b>screen</b> will be ignored if a merged display (like Xinerama) is not
in use, or merged disp