CONCEPT 09 / 87

Cart quantities, removal and undo

Plus/minus paired with a number field makes quantity changes easier. Update totals automatically and let shoppers undo a removed line.

01 / THE PROBLEM

The cart must update its total and provide recovery after removal.

02 / WHEN THIS FITS

A drawer suits quick-add; a full cart page provides space for review. Fixture carts are isolated from the real ReAI cart.

Try the pattern

01
Add an item. Increase to 3: line total, subtotal and cart count should update without a Save button.
02
Decrease from 1 to 0: the line disappears. Undo should restore it.
03
Close with Escape. Focus should return to the control that opened the drawer.
04
Change one line rapidly: the final quantity and total win without repeat catalog requests.
05
Set quantity to zero then undo: restore the right variant, quantity and keyboard focus.

Measure confirmed, deduplicated outcomes per eligible checkout start. Define paid orders and accepted credit orders separately.

Payment errors, duplicate orders, incorrect totals, unclear arrival dates and discount cost. A pay click is only an attempt.

This is a proposed investigation, not a measured result. Choose one hypothesis and define the audience before testing.