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
* context, system-defaults, and other information. The effective value is
 * generally what the user cares about, and is what appears in the property
 * sheet and other UI.
 * <p>
 * Members and classes in the property value system include:
 * <p>
 * <ul>
 * <li>The {@link #propValues}member stores the property values set on this
 * element.</li>
 * <li>The {@link #setProperty( String, Object )}method sets a property value
 * on this element.</li>
 * <li>The {@link #clearProperty}method unsets a property value on this
 * method.</li>
 * <li>The {@link #getLocalProperty( Module, String )}method gets the property
 * value, if any, set on this element.</li>
 * <li>The {@link #getProperty( Module, String )}method gets the effective
 * value of the property.</li>
 * </ul>
 * 
 * <h3>Element Name</h3>
 * 
 * Elements can have a name. The semantics of the specific element type
 * determine if the element name is optional or required. In a few contexts, the
 * name may be ignored (not supported). The name uniquely identifies an element
 * and is locale-independent. (The display name, described below, is
 * localizable.) Elements with a name can be referenced in the design or in
 * code. Elements without a name can be referenced in code by navigating to the
 * element.
 * <p>
 * If an element has a name, then it resides in a name space. All name spaces