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
* @param module
	 *            module
	 * @return the shared style, or null if this element does not explicitly
	 *         reference a shared style.
	 */
	public StyleElement getStyle( Module module )
	{
		return null;
	}
	/**
	 * Returns the shared style referenced by this element. This method will not
	 * try to resolve the style element if the value is un-resolved.
	 * <p>
	 * Part of: Style system.
	 * 
	 * @return the shared style, or null if this element does not explicitly
	 *         reference a shared style, or the value is un-resolved
	 */
	public StyleElement getStyle( )
	{
		return null;
	}
	/**
	 * Caches an element that derives from this element.
	 * <p>
	 * Part of: Inheritance system.
	 * 
	 * @param child
	 *            The new derived element.
	 */