A method that displays the Set up Apple Pay button.
Safari Desktop 10.0.1+
Safari Mobile 10.1+
Apple Pay JS
The merchant ID created when the merchant enrolled in Apple Pay.
This method is available starting in iOS 10.1 and macOS 10.12.1. The code in Listing 1 displays the Set up Apple Pay button if the method is available on a supported device and the user does not have Apple Pay set up yet.
Use the HTML and CSS code in Listing 2 to configure a Set up Apple Pay button for display.