How to create submenus (or multiple command UIs)

I have some UI

Everything into the Command UI is a Imgui::Button inside the callback

    ImGui::InputInt("Radius", &radius);

    ImGui::SameLine();

    //
    // Button
    if (ImGui::Button("Max Curvature"))
    {
        // get mesh
        polyscope::registerSurfaceMesh("mesh", V, F);
        
        // Compute curvature directions via quadric fitting
        MatrixXd PD1, PD2;
        VectorXd PV1, PV2;
        std::vector<Index> bv = {};
        
        igl::principal_curvature(V, F, PD1, PD2, PV1, PV2, bv, radius);
        
        polyscope::getSurfaceMesh("mesh")
            ->addVertexScalarQuantity("Max Curvature", PV1,
                                      polyscope::DataType::SYMMETRIC);
        
    }

pretty standard. Now I'd like to add the "radius" input inside the button scope, so that when I press the button all the relevant data is presented to the user.
Of course, if I simply put the input widget code inside the button one the input widget is just show for an instant then deleted, as the callback runs over and over.
The best option would be to create a separate sub-UI, possibly opening down below the command UI itself. Or to create multiple command UIs.
Is there a way?
Thank you

Issue に示されている Command UI callback と ImGui::InputInt および ImGui::Button の使用から始めてください。永続的な radius input または別の submenu を callback の呼び出し間でも表示し続ける方法を検討し、どのインタラクションを完了とみなすべきかを定義してください。Issue にはファイルやテストの指定はありません。