HistoryListener

```
public interface HistoryListener
```
The listener interface for receiving LocationHistory events. The class that is interested in processing LocationHistory events implements this interface, and the object created with that class is registered with PDFViewerBean, using the addHistoryListener method. When a history event occurs, the relevant method in the HistoryListener is invoked.

Methods
Modifier and Type	Method and Description
`void`	`afterDocumentSet(PDFViewerBean viewerBean)` This method is called after a document is loaded in the PDFViewerBean.
`void`	`beforeDocumentSet(PDFViewerBean viewerBean)` This method is called before a document is loaded in the PDFViewerBean.
`void`	`locationChanged(PDFViewerBean viewerBean, boolean newView)` This method is called when the location in a document is changed including when a new view is added to the `LocationHistory`.
`void`	`nextDocument(PDFViewerBean viewerBean)` This method is called when a request has been made to go to the next Location, but there are no subsequent views in the `LocationHistory` of the current document.
`void`	`previousDocument(PDFViewerBean viewerBean)` This method is called when a request has been made to go to the previous location, but there are no previous views in the `LocationHistory` of the current document.

Interface HistoryListener