diff --git a/src/ui/CSimpleSlider.cpp b/src/ui/CSimpleSlider.cpp
index 032c5c0..bffae29 100644
--- a/src/ui/CSimpleSlider.cpp
+++ b/src/ui/CSimpleSlider.cpp
@@ -127,6 +127,13 @@ void CSimpleSlider::LoadXML(XMLNode* node, CStatus* status) {
     }
 }
 
+void CSimpleSlider::OnFrameSizeChanged(const CRect& rect) {
+    this->CSimpleFrame::OnFrameSizeChanged(rect);
+
+    this->m_changed = 1;
+}
+
+
 void CSimpleSlider::OnLayerHide() {
     this->m_buttonDown = 0;
 
diff --git a/src/ui/CSimpleSlider.hpp b/src/ui/CSimpleSlider.hpp
index 29f5109..d707c33 100644
--- a/src/ui/CSimpleSlider.hpp
+++ b/src/ui/CSimpleSlider.hpp
@@ -39,6 +39,7 @@ class CSimpleSlider : public CSimpleFrame {
         virtual int32_t OnLayerTrackUpdate(const CMouseEvent& evt);
         virtual int32_t OnLayerMouseDown(const CMouseEvent& evt, const char* btn);
         virtual int32_t OnLayerMouseUp(const CMouseEvent& evt, const char* btn);
+        virtual void OnFrameSizeChanged(const CRect& rect);
 
         // Member functions
         CSimpleSlider(CSimpleFrame* parent)