Add item - confirm custom function

OSCART_Thomas

Hi,

Is it possible to add a custom function to the save button of the add item dialog?

It's for the following result:
I have 3 columns:
ID, Category and Order

The only field that has to beel filed in manualy is the category.
The ID is a autonumber but the new row has to automaticly take the last order nr + 1
so I want to add a custom function to calculate the order nr.

Can anybody help me with this?

Thanks for the help!