Function is_focus_within_hgl 

pub fn is_focus_within_hgl(
    child: impl IntoUiNode,
    state: impl IntoVar<bool>,
) -> UiNode

P If the widget or one of its descendants has keyboard focus and the user is using the keyboard to navigate.

To check if only the widget has keyboard focus use is_focused_hgl.

Also see is_focus_within to check if the widget has focus within regardless of highlighting.