Bug 151959 inappropriate screen operation
steps to reproduce: - create a report - add a grid item (3x3) - switch to Outline view - expand the grid item to see its rows and cells - select the grid item, and drag it into any of its own cell expected behavior: - is it an invalid screen operation? if it is, it should be banned actual behavior: - the grid item was disappeared surprisingly
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/core/DesignElement.java
public Module getRoot( )
	{
		DesignElement element = this;
		while ( element.getContainer( ) != null )
			element = element.getContainer( );
		if ( element instanceof Module == false )
			return null;
		return (Module) element;
	}
	/**
	 * Implements to broadcast an event to all listeners of this design element.
	 * Implementations of sendEvent( ) call this to do the actual work of
	 * broadcasting.
	 * <p>
	 * Part of: Notification system.
	 * 
	 * @param ev
	 *            the event to send
	 */
	public final void broadcast( NotificationEvent ev )
	{
		if ( this instanceof Module || getContainer( ) != null )
			broadcast( ev, getRoot( ) );
	}
	/**
	 * Implements to broadcast an event to all listeners of this design element
	 * on a design tree. Note subclasses should override this method to change
	 * the behavior of broadcast method.
	 * 
	 * Part of: Notification system.