Function lv_group_send_data 

pub unsafe extern "C" fn lv_group_send_data(
    group: *mut lv_group_t,
    c: u32,
) -> lv_result_t

Send a control character to Widget that has focus in a group. @param group pointer to a group @param c a character (use LV_KEY_.. to navigate) @return result of Widget with focus in group.