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
*            the module
	 * @param prop
	 *            the definition of property
	 * @return the property value, or null if no value is set.
	 */
	public Object getProperty( Module module, PropertyDefn prop )
	{
		return getProperty( module, (ElementPropertyDefn) prop );
	}
	/**
	 * Returns whether this element is a style. While this information could be
	 * computed from meta-data, it is computed here for performance.
	 * 
	 * @return true if this is a style element, false otherwise.
	 */
	public boolean isStyle( )
	{
		return false;
	}
	/**
	 * Gets a property value given its internal name. This version checks only
	 * this one object. That is, it gets the "local" property value. The
	 * property name must also be valid for this object. The name can be a
	 * built-in property name, or a user-defined property name. The value is set
	 * without checking the name for validity.
	 * <p>
	 * Part of: Property value system.
	 * 
	 * @param module
	 *            the module