Bug 182000 Cross tab layout behavior
In the current approach of cross tab layout view, the arrow is associated with the first data item in the cell. - User cannot delete measure and level data items which have arrow with them. -Wenbin has concerns with the approach, as this will make the UI very restrictive. - Also user may want to delete data item and just show image in a cross tab cell. We had a discussion with Bang, and he has revised the mockups for the layout - The idea is that the arrow is associated with the cross tab cell and not data item. Let us know if there are any issues with supporting this.
xtab/org.eclipse.birt.report.item.crosstab.ui/src/org/eclipse/birt/report/item/crosstab/internal/ui/editors/editpolicies/CrosstabCellFlowLayoutEditPolicy.java
private boolean isFirstDataItem(CrosstabCellAdapter adapter, Object model, String type)
	{
		if (adapter.getPositionType( ).equals( type ))
		{
			return adapter.getFirstDataItem( ) == model;
		}
		return false;
	}
	
	
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.gef.editpolicies.OrderedLayoutEditPolicy#createMoveChildCommand(org.eclipse.gef.EditPart,
	 *      org.eclipse.gef.EditPart)
	 */
	protected Command createMoveChildCommand( EditPart child, EditPart after )
	{
		Object afterModel = null;
		if ( after != null )
		{
			afterModel = after.getModel( );
		}
		CrosstabFlowMoveChildCommand command = new CrosstabFlowMoveChildCommand( child.getModel( ),
				afterModel,
				child.getParent( ).getModel( ) );
		return command;
	}
}