Build a discount extension for Shopify POS

In this tutorial, you'll learn how to do the following tasks:

• Enable or disable the tile based on cart contents.
• Add buttons to the modal that apply a discount and show a toast when tapped.
• Give your extension a useful description.
• Deploy your extension to Shopify, create a version, and publish.

• You've completed the Getting started with POS UI extensions guide.

The sample code imports some extension components to build the UI. The tile contains the logic to control its enablement based on the cart subtotal. The modal contains the logic to apply discounts based on button tap.

You can copy and paste the following code into your index file. You can also update your extension's configuration file following the shopify.extension.toml example.

The rest of the tutorial walks through this sample code step-by-step.

You can enable or disable the tile based on cart contents by accessing its subscribable.

1. In the tile code, initialize state based on the initial value of the subscribable.

2. In the tile code, subscribe to cart changes and mutate state based on the updated cart.

You can add buttons to the modal that trigger some action on press.

1. Create the buttons on the modal. Note that most components belong in a ScrollView.

2. Define an onPress function to apply the discount and show the toast.

Your extension's description will be visible to the merchant when they discover and add it to their POS. When you generate a POS UI Extension from Shopify CLI, the extension description defaults to the name of the extension. You can update the description in the generated toml file (shopify.extension.toml).

Refer to Deploy app extensions for more information.

• Debug POS UI Extension.

• Learn more about building with POS UI extensions by exploring the POS UI extension reference.