NavigatorHandlerExtension
From OpenKM Documentation
Any extension that implements NavigatorHandlerExtension will be watching all events fired from navigator stack panel
Method
Each time it'll be some new stack panel event the method onChange it'll be fired by OpenKM.
Example
public class HandlersTest implements NavigatorHandlerExtension {
@Override
public void onChange(NavigatorEventConstant event) {
Window.alert("navigator event fired");
}
}