Bug 121352 The data set binding property cannot be retrieved in report preview layout
In report preview page, the datasource/dataset property binding lists cannot be retrieved. The dataset binding can not work correctly in layout preview because it's value cannot get from the binding list. But in the data set edit page, the binding value can be got. You can refer to the attachment.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/core/DesignElement.java
/**
	 * Returns a list of user properties defined in this element and somewhere
	 * up the inheritance chain.
	 * 
	 * @return The list of user properties.
	 */
	public List getUserProperties( )
	{
		List props = new ArrayList( );
		DesignElement e = this;
		while ( e != null )
		{
			List prop = e.getLocalUserProperties( );
			if ( prop != null )
			{
				props.addAll( prop );
			}
			e = e.getExtendsElement( );
		}
		return props;
	}
	/**
	 * Returns a list of user properties that are defined only on this element.
	 * 
	 * @return The list of user properties.
	 */
	public List getLocalUserProperties( )
	{
		if ( userProperties == null )
			return Collections.EMPTY_LIST;