Constructs a new instance of this class given only its parent.
@param parent a shell which will be the parent of the new instance
@exception IllegalArgumentException <ul>
<li>ERROR_NULL_ARGUMENT - if the parent is null</li>
</ul>
@exception SWTException <ul>
<li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the parent</li>
<li>ERROR_INVALID_SUBCLASS - if this class is not an allowed subclass</li>
</ul>
Constructs a new instance of this class given only its parent.
@param parent a shell which will be the parent of the new instance
@exception IllegalArgumentException <ul> <li>ERROR_NULL_ARGUMENT - if the parent is null</li> </ul> @exception SWTException <ul> <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the parent</li> <li>ERROR_INVALID_SUBCLASS - if this class is not an allowed subclass</li> </ul>