Propagate an enum class to a higher level class

This is a fairly basic problem but I'd like some input on what the best practice is. My issue is how do you propagate an enum from a sub-class to a higher level class so that it is visible to the main class's caller?

For example, say I have a class Bike. Bike will initialize sub-classes Wheel, Frame, Chain, etc. that make up a bike. Frame might have an enum such as FrameColor, Chain might have an enum such as LinkType, etc. Now let's say some higher level code wants to construct a Bike class. The constructor of Bike would require the caller to specify the LinkType, FrameColor, etc. I'd like to avoid putting the enum definitions inside a global header file, since this is bad C++ style.

Two possible approaches I've thought of but there must be a simpler, cleaner way:

Use an abstract class defining an interface
Forward declare the enum

Solution

Why do you need to propagate anything? As like as your subobjects have their enumerations clear, you can just use them directly. Once you have Frame::Color, you don't need to make a Bike::Frame::Color... the one is sufficient. For example:

struct Frame {
    enum class Color {
        BLACK, RED
    };

    Color c;
};

struct Bike {
    Bike(Frame::Color c /*, Chain::LinkType lt, ..., */)
        : frame{c}
    { }

    Frame frame;
};

int main() {
    Bike b{Frame::Color::RED};
}

Now, if Frame is nested inside of Bike, you can just alias the enum:

struct Bike {
    struct Frame {
        enum class Color { ... };
    };

    using FrameColor = Frame::Color;
};

Bike b{Bike::FrameColor::RED};