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
return derived != null && derived.size( ) > 0;
	}
	/**
	 * Returns the optional display name. Note: set the display name by calling
	 * the {@link #setProperty( String, Object )}method.
	 * <p>
	 * Part of: The name system.
	 * 
	 * @return Returns the displayName.
	 */
	public String getDisplayName( )
	{
		return (String) getLocalProperty( null, DISPLAY_NAME_PROP );
	}
	/**
	 * Returns the optional message id used to localize the display name. Note:
	 * set the display name id by calling the
	 * {@link #setProperty( String, Object )}method.
	 * <p>
	 * Part of: The name system.
	 * 
	 * @return Returns the displayNameID.
	 */
	public String getDisplayNameID( )
	{
		return (String) getLocalProperty( null, DISPLAY_NAME_ID_PROP );
	}
	/**
	 * Sets the unique ID for this element. The ID can be set only once, when
	 * the element is first added to the design.