diff --git a/samples/dataview/mymodels.cpp b/samples/dataview/mymodels.cpp
index 3d19ca351e..03c13cd356 100644
--- a/samples/dataview/mymodels.cpp
+++ b/samples/dataview/mymodels.cpp
@@ -156,7 +156,7 @@ void MyMusicTreeModel::Delete( const wxDataViewItem &item )
 }
 
 int MyMusicTreeModel::Compare( const wxDataViewItem &item1, const wxDataViewItem &item2,
-                               unsigned int column, bool ascending )
+                               unsigned int column, bool ascending ) const
 {
     wxASSERT(item1.IsOk() && item2.IsOk());
         // should never happen
diff --git a/samples/dataview/mymodels.h b/samples/dataview/mymodels.h
index 9a926ddc34..ba4397c1f1 100644
--- a/samples/dataview/mymodels.h
+++ b/samples/dataview/mymodels.h
@@ -141,7 +141,7 @@ public:
     // override sorting to always sort branches ascendingly
 
     int Compare( const wxDataViewItem &item1, const wxDataViewItem &item2,
-                 unsigned int column, bool ascending );
+                 unsigned int column, bool ascending ) const;
 
     // implementation of base class virtuals to define model