fix(auth): expose slot parameters through FirebaseAuthScreen

app/src/main/AndroidManifest.xml

@@ -55,6 +55,30 @@
             android:label="Custom Slots & Theming Demo"
             android:exported="false"
             android:theme="@style/Theme.FirebaseUIAndroid" />
+
+        <activity
+            android:name=".EmailAuthSlotDemoActivity"
+            android:label="Email Auth — Custom Slot"
+            android:exported="false"
+            android:theme="@style/Theme.FirebaseUIAndroid" />
+
+        <activity
+            android:name=".PhoneAuthSlotDemoActivity"
+            android:label="Phone Auth — Custom Slot"
+            android:exported="false"
+            android:theme="@style/Theme.FirebaseUIAndroid" />
+
+        <activity
+            android:name=".ShapeCustomizationDemoActivity"
+            android:label="Shape Customization"
+            android:exported="false"
+            android:theme="@style/Theme.FirebaseUIAndroid" />
+
+        <activity
+            android:name=".CustomMethodPickerDemoActivity"
+            android:label="Custom Method Picker Layout"
+            android:exported="false"
+            android:theme="@style/Theme.FirebaseUIAndroid" />
     </application>
 
 </manifest>

app/src/main/java/com/firebaseui/android/demo/CustomMethodPickerDemoActivity.kt

@@ -0,0 +1,318 @@
+package com.firebaseui.android.demo
+
+import android.os.Bundle
+import android.util.Log
+import androidx.activity.ComponentActivity
+import androidx.activity.compose.setContent
+import androidx.activity.enableEdgeToEdge
+import androidx.compose.foundation.Image
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.PaddingValues
+import androidx.compose.foundation.layout.Spacer
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.height
+import androidx.compose.foundation.layout.size
+import androidx.compose.foundation.lazy.LazyColumn
+import androidx.compose.foundation.lazy.LazyRow
+import androidx.compose.foundation.lazy.items
+import androidx.compose.foundation.shape.CircleShape
+import androidx.compose.material3.Button
+import androidx.compose.material3.ButtonDefaults
+import androidx.compose.material3.HorizontalDivider
+import androidx.compose.material3.Icon
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Surface
+import androidx.compose.material3.Text
+import androidx.compose.material3.TextButton
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.graphics.painter.Painter
+import androidx.compose.ui.graphics.vector.rememberVectorPainter
+import androidx.compose.ui.res.painterResource
+import androidx.compose.ui.text.font.FontWeight
+import androidx.compose.ui.text.style.TextAlign
+import androidx.compose.ui.unit.dp
+import com.firebase.ui.auth.AuthException
+import com.firebase.ui.auth.FirebaseAuthUI
+import com.firebase.ui.auth.configuration.authUIConfiguration
+import com.firebase.ui.auth.configuration.auth_provider.AuthProvider
+import com.firebase.ui.auth.configuration.string_provider.LocalAuthUIStringProvider
+import com.firebase.ui.auth.configuration.theme.AuthUIAsset
+import com.firebase.ui.auth.configuration.theme.AuthUITheme
+import com.firebase.ui.auth.configuration.theme.ProviderStyleDefaults
+import com.firebase.ui.auth.ui.components.AuthProviderButton
+import com.firebase.ui.auth.ui.screens.FirebaseAuthScreen
+
+class CustomMethodPickerDemoActivity : ComponentActivity() {
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        enableEdgeToEdge()
+
+        val authUI = FirebaseAuthUI.getInstance()
+
+        val configuration = authUIConfiguration {
+            context = applicationContext
+            logo = AuthUIAsset.Resource(R.drawable.firebase_auth)
+            tosUrl = "https://policies.google.com/terms"
+            privacyPolicyUrl = "https://policies.google.com/privacy"
+            providers {
+                provider(
+                    AuthProvider.Google(
+                        scopes = listOf("email"),
+                        serverClientId = "406099696497-a12gakvts4epfk5pkio7dphc1anjiggc.apps.googleusercontent.com",
+                    )
+                )
+                provider(AuthProvider.Apple(customParameters = emptyMap(), locale = null))
+                provider(AuthProvider.Facebook())
+                provider(AuthProvider.Twitter(customParameters = emptyMap()))
+                provider(AuthProvider.Github(customParameters = emptyMap()))
+                provider(AuthProvider.Microsoft(tenant = null, customParameters = emptyMap()))
+                provider(AuthProvider.Yahoo(customParameters = emptyMap()))
+                provider(
+                    AuthProvider.GenericOAuth(
+                        providerName = "Discord",
+                        providerId = "oidc.discord",
+                        scopes = emptyList(),
+                        customParameters = emptyMap(),
+                        buttonLabel = "Sign in with Discord",
+                        buttonIcon = AuthUIAsset.Resource(R.drawable.ic_discord_24dp),
+                        buttonColor = Color(0xFF5865F2),
+                        contentColor = Color.White
+                    )
+                )
+                provider(
+                    AuthProvider.GenericOAuth(
+                        providerName = "LINE",
+                        providerId = "oidc.line",
+                        scopes = emptyList(),
+                        customParameters = emptyMap(),
+                        buttonLabel = "Sign in with LINE",
+                        buttonIcon = AuthUIAsset.Resource(R.drawable.ic_line_logo_24dp),
+                        buttonColor = Color(0xFF06C755),
+                        contentColor = Color.White
+                    )
+                )
+                provider(
+                    AuthProvider.Email(
+                        emailLinkActionCodeSettings = null,
+                        passwordValidationRules = emptyList()
+                    )
+                )
+                provider(
+                    AuthProvider.Phone(
+                        defaultNumber = null,
+                        defaultCountryCode = null,
+                        allowedCountries = null
+                    )
+                )
+                provider(AuthProvider.Anonymous)
+            }
+        }
+
+        setContent {
+            AuthUITheme {
+                Surface(
+                    modifier = Modifier.fillMaxSize(),
+                    color = MaterialTheme.colorScheme.background
+                ) {
+                    FirebaseAuthScreen(
+                        configuration = configuration,
+                        authUI = authUI,
+                        onSignInSuccess = { result ->
+                            Log.d("CustomMethodPickerDemo", "Auth success: ${result.user?.uid}")
+                        },
+                        onSignInFailure = { exception: AuthException ->
+                            Log.e("CustomMethodPickerDemo", "Auth failed", exception)
+                        },
+                        onSignInCancelled = {
+                            Log.d("CustomMethodPickerDemo", "Auth cancelled")
+                        },
+                        customMethodPickerLayout = { providers, onProviderSelected ->
+                            SpotlightMethodPicker(
+                                providers = providers,
+                                onProviderSelected = onProviderSelected
+                            )
+                        }
+                    )
+                }
+            }
+        }
+    }
+}
+
+@Composable
+fun SpotlightMethodPicker(
+    providers: List<AuthProvider>,
+    onProviderSelected: (AuthProvider) -> Unit,
+) {
+    val stringProvider = LocalAuthUIStringProvider.current
+
+    val groups = providers.groupBy {
+        when (it) {
+            is AuthProvider.Google, is AuthProvider.Apple -> "featured"
+            is AuthProvider.Email, is AuthProvider.Phone -> "credential"
+            is AuthProvider.Anonymous -> "anonymous"
+            else -> "social"
+        }
+    }
+    val featured = groups.getOrElse("featured") { emptyList() }
+    val social = groups.getOrElse("social") { emptyList() }
+    val credential = groups.getOrElse("credential") { emptyList() }
+    val anonymous = groups["anonymous"]?.firstOrNull()
+
+    LazyColumn(
+        modifier = Modifier.fillMaxSize(),
+        contentPadding = PaddingValues(vertical = 48.dp),
+        verticalArrangement = Arrangement.spacedBy(12.dp),
+        horizontalAlignment = Alignment.CenterHorizontally,
+    ) {
+        item {
+            Text(
+                text = "Sign in",
+                style = MaterialTheme.typography.headlineMedium.copy(fontWeight = FontWeight.Bold),
+                textAlign = TextAlign.Center,
+                modifier = Modifier.padding(horizontal = 32.dp)
+            )
+            Spacer(modifier = Modifier.height(8.dp))
+            Text(
+                text = "Choose how you'd like to continue",
+                style = MaterialTheme.typography.bodyMedium,
+                color = MaterialTheme.colorScheme.onSurfaceVariant,
+                textAlign = TextAlign.Center,
+                modifier = Modifier.padding(horizontal = 32.dp)
+            )
+            Spacer(modifier = Modifier.height(24.dp))
+        }
+
+        items(featured) { provider ->
+            AuthProviderButton(
+                modifier = Modifier
+                    .fillMaxWidth()
+                    .padding(horizontal = 32.dp),
+                provider = provider,
+                onClick = { onProviderSelected(provider) },
+                stringProvider = stringProvider
+            )
+        }
+
+        if (social.isNotEmpty()) {
+            item {
+                Spacer(modifier = Modifier.height(4.dp))
+                HorizontalDivider(
+                    color = MaterialTheme.colorScheme.outlineVariant,
+                    modifier = Modifier.padding(horizontal = 32.dp)
+                )
+                Spacer(modifier = Modifier.height(4.dp))
+            }
+            item {
+                LazyRow(
+                    modifier = Modifier.fillMaxWidth(),
+                    horizontalArrangement = Arrangement.spacedBy(12.dp),
+                    contentPadding = PaddingValues(horizontal = 16.dp)
+                ) {
+                    items(social) { provider ->
+                        val style = styleForProvider(provider)
+                        ProviderIconButton(
+                            style = style,
+                            contentDescription = provider.providerId,
+                            onClick = { onProviderSelected(provider) }
+                        )
+                    }
+                }
+            }
+        }
+
+        if (credential.isNotEmpty()) {
+            item {
+                Spacer(modifier = Modifier.height(4.dp))
+                HorizontalDivider(
+                    color = MaterialTheme.colorScheme.outlineVariant,
+                    modifier = Modifier.padding(horizontal = 32.dp)
+                )
+                Spacer(modifier = Modifier.height(4.dp))
+            }
+            items(credential) { provider ->
+                AuthProviderButton(
+                    modifier = Modifier
+                        .fillMaxWidth()
+                        .padding(horizontal = 32.dp),
+                    provider = provider,
+                    onClick = { onProviderSelected(provider) },
+                    stringProvider = stringProvider
+                )
+            }
+        }
+
+        anonymous?.let {
+            item {
+                Spacer(modifier = Modifier.height(8.dp))
+                TextButton(onClick = { onProviderSelected(it) }) {
+                    Text("Continue as guest")
+                }
+            }
+        }
+    }
+}
+
+@Composable
+private fun ProviderIconButton(
+    style: AuthUITheme.ProviderStyle,
+    contentDescription: String,
+    onClick: () -> Unit,
+) {
+    Button(
+        onClick = onClick,
+        modifier = Modifier.size(52.dp),
+        shape = CircleShape,
+        colors = ButtonDefaults.buttonColors(containerColor = style.backgroundColor),
+        contentPadding = PaddingValues(0.dp),
+        elevation = ButtonDefaults.buttonElevation(defaultElevation = style.elevation)
+    ) {
+        style.icon?.let { asset ->
+            val painter = asset.asPainter()
+            val tint = style.iconTint
+            if (tint != null) {
+                Icon(
+                    painter = painter,
+                    contentDescription = contentDescription,
+                    tint = tint,
+                    modifier = Modifier.size(22.dp)
+                )
+            } else {
+                Image(
+                    painter = painter,
+                    contentDescription = contentDescription,
+                    modifier = Modifier.size(22.dp)
+                )
+            }
+        }
+    }
+}
+
+@Composable
+private fun AuthUIAsset.asPainter(): Painter = when (this) {
+    is AuthUIAsset.Resource -> painterResource(resId)
+    is AuthUIAsset.Vector -> rememberVectorPainter(image)
+}
+
+private fun styleForProvider(provider: AuthProvider): AuthUITheme.ProviderStyle = when (provider) {
+    is AuthProvider.Facebook -> ProviderStyleDefaults.Facebook
+    is AuthProvider.Twitter -> ProviderStyleDefaults.Twitter
+    is AuthProvider.Github -> ProviderStyleDefaults.Github
+    is AuthProvider.Microsoft -> ProviderStyleDefaults.Microsoft
+    is AuthProvider.Yahoo -> ProviderStyleDefaults.Yahoo
+    is AuthProvider.GenericOAuth -> AuthUITheme.ProviderStyle(
+        icon = provider.buttonIcon,
+        backgroundColor = provider.buttonColor ?: Color(0xFF666666),
+        contentColor = provider.contentColor ?: Color.White
+    )
+    else -> AuthUITheme.ProviderStyle(
+        icon = null,
+        backgroundColor = Color(0xFF666666),
+        contentColor = Color.White
+    )
+}