Help Calculating total of column - custom theme

Hello people
as the software for the moment doesn’t support total of columns
except in custom themes
and we are not all programmers, may be some more experienced user can help
and i think a lot of users will find it useful

-how to calculate and add total at the end of “Qty” column
or in an user added custom field.

-how to calculate and add total at the end of “Qty” column for choosen Unit Names
(i think there are users and cases when you dont need to calculate all for example in the same invoice different items in Kg + transport service, we need total Kg for the items not +1 transport service,
or example. different items in Kg + bags in pcs )

i saw the tutorial for field 1 + field 2 in the guides but it doesn’t help in this particular case

maybe some skilled user can be of help

Hi , has there been any progress on this topic ?

I was just thinking how handy it would be to be able to total the quantities column …

Wishful thinking