Returns the receiver's horizontal scroll bar if it has
one, and null if it does not.
@return the horizontal scroll bar (or null)
@exception SWTException <ul>
<li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
<li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
</ul>
Returns the receiver's horizontal scroll bar if it has one, and null if it does not.
@return the horizontal scroll bar (or null)
@exception SWTException <ul> <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> </ul>