The watermark plugin for QGIS demonstrates the basic usage of the QgsPluginLayer API.
QGIS watermark plugin is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.
Copyright © 2009 Matthias Walker & Pirmin Kalberer, Sourcepole AG