diff --git a/core/view.h b/core/view.h
index 017545248..f44803ba3 100644
--- a/core/view.h
+++ b/core/view.h
@@ -69,6 +69,11 @@ class OKULAR_EXPORT View
          */
         QString name() const;
 
+        /**
+         * Must return an unique ID for each view.
+         */
+        virtual uint viewId() const = 0;
+
         /**
          * Query whether the view support the specified @p capability.
          */
diff --git a/ui/pageview.h b/ui/pageview.h
index 6770f5bbe..681391dd4 100644
--- a/ui/pageview.h
+++ b/ui/pageview.h
@@ -81,6 +81,7 @@ Q_OBJECT
         bool canUnloadPixmap( int pageNum ) const;
 
         // inherited from View
+        uint viewId() const { return observerId(); }
         bool supportsCapability( ViewCapability capability ) const;
         CapabilityFlags capabilityFlags( ViewCapability capability ) const;
         QVariant capability( ViewCapability capability ) const;