Check the documentation for Wx::Sizer again. Since it doesn't inherit from Wx::Window, its Hide method works a bit differently than a normal window. There are three different method signatures listed for the Hide method:

bool Hide(wxWindow* window, bool recursive = false)
bool Hide(wxSizer* sizer, bool recursive = false)
bool Hide(size_t index)
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Since they all take one or more arguments, the error you are getting means that the binding couldn't pick between the available methods because none of them match your method call.

I'm not sure exactly what you are trying to do so I can't tell you which set of arguments you want to use, but hopefully this will point you in the right direction.