Screen Providers Reference

Every screen in msa-core is a ComposableScreen<State, Action>: your Composable receives an immutable State and a triggerAction callback.

fun interface ComposableScreen<S, A> {
    @Composable
    fun Content(state: S, triggerAction: (A) -> Unit)
}

You create one from a lambda:

ComposableScreen<LoginState, LoginAction> { state, triggerAction -> MyLoginScreen(state, triggerAction) }

How the screens are organised

ScreenProviders groups the screens by feature. Each group is an interface in com.theminesec.multiplatform.msa_core.app.contract.screens, and msa-uikit provides an open default class for each one:

interface ScreenProviders {
    val statusBarColor: @Composable (AppScreen) -> Color
    val themeWrapper: @Composable (content: @Composable () -> Unit) -> Unit
 
    val startup: StartupScreens
    val home: HomeScreens
    val payment: PaymentScreens
    val history: HistoryScreens
    val settlement: SettlementScreens
    val settings: SettingsScreens
    val idle: IdleScreens
 
    // App2App screens (see below)
}

To replace one screen, subclass DefaultScreenProviders, then override the group with a subclass of its default class, and override the one slot. Every other slot keeps tracking msa-uikit:

class MyScreenProviders : DefaultScreenProviders(MyBrandTheme) {
    override val history: HistoryScreens = object : DefaultHistoryScreens() {
        override val detail = ComposableScreen { state, triggerAction ->
            MyTransactionDetail(state, triggerAction)
        }
    }
}

Declare slots as stored properties (override val x = ...), never as getters. A getter creates a new screen on every read and forces recomposition.

Replacing a screen changes only how it looks. msa-core validates every operation, whatever the UI offers.

Startup: startup

Default class: DefaultStartupScreens

Home: home

Default class: DefaultHomeScreens

Payment: payment

Default class: DefaultPaymentScreens. One payment, from the amount to the receipt.

The result of a payment is shown by history.detail: a transaction that just ran is the same record as one looked up later.

History: history

Default class: DefaultHistoryScreens

Settlement: settlement

Default class: DefaultSettlementScreens

Settings: settings

Default class: DefaultSettingsScreens

Idle: idle

Default class: DefaultIdleScreens. What an unattended (kiosk) terminal shows when nobody is using it.

App-to-App Screens

These screens are shown when a POS app on the same device calls MineSec Pay 7 through App2App. They are direct properties of ScreenProviders, not a group.

Override them directly in your DefaultScreenProviders subclass:

override val saleApp2AppScreen = ComposableScreen { state, triggerAction ->
    MyApp2AppSaleScreen(state, triggerAction)
}

Where the classes live

Your IDE's auto-import resolves them.

Status Bar Colour

statusBarColor picks the status bar colour for each screen. The stock implementation:

override val statusBarColor: @Composable (AppScreen) -> Color = { screen ->
    when (screen) {
        LandingScreen -> MsaTheme.colors.mutedForeground
        LoginScreen -> MsaTheme.colors.background
        HomeScreen -> MsaTheme.colors.surface
        AmountEntryScreen -> MsaTheme.colors.primary
        else -> MsaTheme.colors.background
    }
}

Override it in your DefaultScreenProviders subclass to change it.

Theme Wrapper

themeWrapper wraps the screens drawn outside the main activity: App2App and the card prompt. Override it with your theme so that those screens are branded too. See Applying your theme.