Function bar 

pub fn bar<R>(
    ui: &mut Ui,
    add_contents: impl FnOnce(&mut Ui) -> R,
) -> InnerResponse<R>

👎Deprecated:

Use egui::MenuBar::new().ui( instead

The menu bar goes well in a crate::Panel::top, but can also be placed in a crate::Window. In the latter case you may want to wrap it in Frame.