Virtual method not callable

I have the base class Panel, which stores some information about the window, then I have subclasses for all the controls: Button, Label, etc. In the base class, I have a method virtual void ApplySchemeSettings(Scheme* scheme) { }that is called inside the constructor Panel(Panel* parent). But instead of a subclass, it is called ApplySchemeSettingsfrom the base class ( Panel).

class Panel
{
    [...]

public:
    virtual void ApplySchemeSettings(Scheme* scheme) { };

    Panel(Panel* parent)
    {
        [...]

        this->ApplySchemeSettings(scheme());
    };
}

class Frame : public Panel
{
    [...]

public:
    void ApplySchemeSettings(Scheme* scheme)
    {
        this->border = scheme->GetBorder("FrameBorder");
    }
}

I cannot declare ApplySchemeSettingsabstractly because subclasses are made by the user.