diff --git a/samples/treectrl/treetest.cpp b/samples/treectrl/treetest.cpp
index 652b596312..fddda848c3 100644
--- a/samples/treectrl/treetest.cpp
+++ b/samples/treectrl/treetest.cpp
@@ -703,12 +703,12 @@ void MyFrame::OnToggleStates(wxCommandEvent& WXUNUSED(event))
 {
     if ( wxGetApp().ShowStates() )
     {
-        m_treeCtrl->CreateStateImageList(true);
+        m_treeCtrl->SetStateImageList(nullptr);
         wxGetApp().SetShowStates(false);
     }
     else
     {
-        m_treeCtrl->CreateStateImageList(false);
+        m_treeCtrl->CreateStateImageList();
         wxGetApp().SetShowStates(true);
     }
 }
@@ -1035,14 +1035,8 @@ void MyTreeCtrl::CreateImages(int size)
     SetImages(images);
 }
 
-void MyTreeCtrl::CreateStateImageList(bool del)
+void MyTreeCtrl::CreateStateImageList()
 {
-    if ( del )
-    {
-        SetStateImageList(nullptr);
-        return;
-    }
-
     wxImageList *states;
     wxBusyCursor wait;
 
diff --git a/samples/treectrl/treetest.h b/samples/treectrl/treetest.h
index dc7d190b6a..24a751c34c 100644
--- a/samples/treectrl/treetest.h
+++ b/samples/treectrl/treetest.h
@@ -113,7 +113,7 @@ public:
     void CreateImages(int size);
 
     void CreateButtonsImageList(int size = 11);
-    void CreateStateImageList(bool del = false);
+    void CreateStateImageList();
 
     void AddTestItemsToTree(size_t numChildren, size_t depth);