+ wxDatePickerCtrl* ctrl = (wxDatePickerCtrl*) wnd;
+ wxASSERT( ctrl && ctrl->IsKindOf(CLASSINFO(wxDatePickerCtrl)) );
+
+ wxDateProperty* prop = wxDynamicCast(property, wxDateProperty);
+
+ if ( prop )
+ {
+ int datePickerStyle = prop->GetDatePickerStyle();
+ if ( datePickerStyle & wxDP_ALLOWNONE )
+ ctrl->SetValue(wxInvalidDateTime);
+ }