designsystem/com.siddharth.kmp.designsystem/WalletPayButton

WalletPayButton

fun WalletPayButton(availability: WalletAvailability, allowedPaymentMethodsJson: String, onClick: () -> Unit, modifier: Modifier = Modifier)(source)

The device-wallet pay button: Apple's PKPaymentButton on iOS, Google's PayButton on Android.

This is the one component in the design system that is deliberately NOT ours. Both vendors mandate their own button asset in their brand guidelines, and both enforce it at review: a hand-drawn "Pay with Apple Pay" mark is a store rejection, not a styling decision. So the composable is a thin, gated wrapper and nothing about its appearance is themeable here.

Declared in an android+ios intermediate source set rather than commonMain. Desktop and browser have no wallet, so they get no declaration at all — an expect in commonMain would oblige them to supply an actual, and the only actual they could supply is an empty one that draws nothing while compiling perfectly.

The availability gate lives here, once, rather than in each actual. It is the whole point of the four-state flag: a button that is drawn and then fails is worse than no button, so anything short of WalletAvailability.AVAILABLE renders nothing and the caller shows its own fallback (a card form, or an "add a card to your wallet" hint for WalletAvailability.NO_CARDS_PROVISIONED).

Parameters

allowedPaymentMethodsJson

Google Pay's allowedPaymentMethods JSON array, as produced by GooglePayRequestBuilder.isReadyToPayRequest(). Required by PayButton, which renders the accepted networks inside the mark. Ignored on iOS — PKPaymentButton carries no request; Apple's networks are declared in the PKPaymentRequest at authorization time instead.