Sets the background pattern. The default value is <code>null</code>.
<p>
This operation requires the operating system's advanced
graphics subsystem which may not be available on some
platforms.
</p>
@param pattern the new background pattern
@exception IllegalArgumentException <ul>
<li>ERROR_INVALID_ARGUMENT - if the parameter has been disposed</li>
</ul>
@exception SWTException <ul>
<li>ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed</li>
<li>ERROR_NO_GRAPHICS_LIBRARY - if advanced graphics are not available</li>
</ul>
Sets the background pattern. The default value is <code>null</code>. <p> This operation requires the operating system's advanced graphics subsystem which may not be available on some platforms. </p>
@param pattern the new background pattern
@exception IllegalArgumentException <ul> <li>ERROR_INVALID_ARGUMENT - if the parameter has been disposed</li> </ul> @exception SWTException <ul> <li>ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed</li> <li>ERROR_NO_GRAPHICS_LIBRARY - if advanced graphics are not available</li> </ul>
@see Pattern @see #getAdvanced @see #setAdvanced
@since 3.1