Add compose bottom chrome.

app/src/main/java/org/thoughtcrime/securesms/main/MainBottomChrome.kt

@@ -0,0 +1,162 @@
+/*
+ * Copyright 2025 Signal Messenger, LLC
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+package org.thoughtcrime.securesms.main
+
+import androidx.annotation.ColorRes
+import androidx.compose.animation.animateContentSize
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.material3.SnackbarDuration
+import androidx.compose.material3.SnackbarHostState
+import androidx.compose.material3.SnackbarResult
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.runtime.remember
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import org.signal.core.ui.compose.Previews
+import org.signal.core.ui.compose.SignalPreview
+import org.signal.core.ui.compose.Snackbars
+import org.thoughtcrime.securesms.R
+import org.thoughtcrime.securesms.megaphone.Megaphone
+import org.thoughtcrime.securesms.megaphone.MegaphoneActionController
+import org.thoughtcrime.securesms.megaphone.Megaphones
+
+data class SnackbarState(
+  val message: String,
+  val actionState: ActionState?,
+  val showProgress: Boolean = false,
+  val duration: SnackbarDuration = SnackbarDuration.Long
+) {
+  data class ActionState(
+    val action: String,
+    @ColorRes val color: Int = R.color.core_white,
+    val onActionClick: () -> Unit
+  )
+}
+
+interface MainBottomChromeCallback {
+  fun onNewChatClick()
+  fun onNewCallClick()
+  fun onCameraClick(destination: MainNavigationDestination)
+  fun onMegaphoneVisible(megaphone: Megaphone)
+  fun onSnackbarDismissed()
+
+  object Empty : MainBottomChromeCallback {
+    override fun onNewChatClick() = Unit
+    override fun onNewCallClick() = Unit
+    override fun onCameraClick(destination: MainNavigationDestination) = Unit
+    override fun onMegaphoneVisible(megaphone: Megaphone) = Unit
+    override fun onSnackbarDismissed() = Unit
+  }
+}
+
+data class MainBottomChromeState(
+  val destination: MainNavigationDestination = MainNavigationDestination.CHATS,
+  val megaphoneState: MainMegaphoneState = MainMegaphoneState(),
+  val snackbarState: SnackbarState? = null
+)
+
+/**
+ * Stack of bottom chrome components:
+ * - The Floating Action buttons
+ * - The megaphone view
+ * - The snackbar
+ */
+@Composable
+fun MainBottomChrome(
+  state: MainBottomChromeState,
+  callback: MainBottomChromeCallback,
+  megaphoneActionController: MegaphoneActionController
+) {
+  Column(
+    modifier = Modifier
+      .fillMaxWidth()
+      .animateContentSize()
+  ) {
+    Box(
+      contentAlignment = Alignment.CenterEnd,
+      modifier = Modifier.fillMaxWidth()
+    ) {
+      MainFloatingActionButtons(
+        destination = state.destination,
+        onCameraClick = callback::onCameraClick,
+        onNewCallClick = callback::onNewCallClick,
+        onNewChatClick = callback::onNewChatClick
+      )
+    }
+
+    MainMegaphoneContainer(
+      state = state.megaphoneState,
+      controller = megaphoneActionController,
+      onMegaphoneVisible = callback::onMegaphoneVisible
+    )
+
+    MainSnackbar(
+      snackbarState = state.snackbarState,
+      onDismissed = callback::onSnackbarDismissed
+    )
+  }
+}
+
+@Composable
+private fun MainSnackbar(
+  snackbarState: SnackbarState?,
+  onDismissed: () -> Unit
+) {
+  val hostState = remember { SnackbarHostState() }
+
+  Snackbars.Host(hostState)
+
+  LaunchedEffect(snackbarState) {
+    if (snackbarState != null) {
+      val result = hostState.showSnackbar(
+        message = snackbarState.message
+      )
+
+      when (result) {
+        SnackbarResult.Dismissed -> Unit
+        SnackbarResult.ActionPerformed -> snackbarState.actionState
+      }
+
+      onDismissed()
+    }
+  }
+}
+
+@SignalPreview
+@Composable
+fun MainBottomChromePreview() {
+  Previews.Preview {
+    val megaphone = remember {
+      Megaphone.Builder(Megaphones.Event.ONBOARDING, Megaphone.Style.ONBOARDING).build()
+    }
+
+    Box(
+      contentAlignment = Alignment.BottomCenter,
+      modifier = Modifier.fillMaxSize()
+    ) {
+      MainBottomChrome(
+        state = MainBottomChromeState(
+          megaphoneState = MainMegaphoneState(
+            megaphone = megaphone
+          ),
+          snackbarState = SnackbarState(
+            message = "Test Message",
+            actionState = SnackbarState.ActionState(
+              action = "Ok",
+              onActionClick = {}
+            )
+          )
+        ),
+        callback = MainBottomChromeCallback.Empty,
+        megaphoneActionController = EmptyMegaphoneActionController
+      )
+    }
+  }
+}

app/src/main/java/org/thoughtcrime/securesms/main/MainFloatingActionButtons.kt

@@ -0,0 +1,196 @@
+/*
+ * Copyright 2025 Signal Messenger, LLC
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+package org.thoughtcrime.securesms.main
+
+import androidx.compose.animation.AnimatedContent
+import androidx.compose.animation.AnimatedVisibility
+import androidx.compose.animation.EnterTransition
+import androidx.compose.animation.ExitTransition
+import androidx.compose.animation.slideInVertically
+import androidx.compose.animation.slideOutVertically
+import androidx.compose.animation.togetherWith
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.height
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.size
+import androidx.compose.foundation.shape.RoundedCornerShape
+import androidx.compose.material3.FilledTonalIconButton
+import androidx.compose.material3.Icon
+import androidx.compose.material3.IconButtonColors
+import androidx.compose.material3.IconButtonDefaults
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.draw.shadow
+import androidx.compose.ui.graphics.vector.ImageVector
+import androidx.compose.ui.platform.LocalDensity
+import androidx.compose.ui.res.vectorResource
+import androidx.compose.ui.unit.dp
+import org.signal.core.ui.compose.Previews
+import org.signal.core.ui.compose.SignalPreview
+import org.signal.core.ui.compose.theme.SignalTheme
+import org.thoughtcrime.securesms.R
+import kotlin.math.roundToInt
+
+private val ACTION_BUTTON_SIZE = 56.dp
+private val ACTION_BUTTON_SPACING = 16.dp
+
+@Composable
+fun MainFloatingActionButtons(
+  destination: MainNavigationDestination,
+  onNewChatClick: () -> Unit = {},
+  onCameraClick: (MainNavigationDestination) -> Unit = {},
+  onNewCallClick: () -> Unit = {}
+) {
+  val boxHeightDp = (ACTION_BUTTON_SIZE * 2 + ACTION_BUTTON_SPACING)
+  val boxHeightPx = with(LocalDensity.current) {
+    boxHeightDp.toPx().roundToInt()
+  }
+
+  Box(
+    modifier = Modifier
+      .padding(ACTION_BUTTON_SPACING)
+      .height(boxHeightDp)
+  ) {
+    AnimatedVisibility(
+      visible = destination == MainNavigationDestination.CHATS,
+      modifier = Modifier.align(Alignment.TopCenter),
+      enter = slideInVertically(initialOffsetY = { boxHeightPx - it }),
+      exit = slideOutVertically(targetOffsetY = { boxHeightPx - it })
+    ) {
+      CameraButton(
+        colors = IconButtonDefaults.filledTonalIconButtonColors().copy(
+          containerColor = SignalTheme.colors.colorSurface1
+        ),
+        onClick = {
+          onCameraClick(MainNavigationDestination.CHATS)
+        }
+      )
+    }
+
+    AnimatedContent(
+      targetState = destination,
+      modifier = Modifier.align(Alignment.BottomCenter),
+      transitionSpec = { EnterTransition.None togetherWith ExitTransition.None }
+    ) { targetState ->
+      when (targetState) {
+        MainNavigationDestination.CHATS -> NewChatButton(onNewChatClick)
+        MainNavigationDestination.CALLS -> NewCallButton(onNewCallClick)
+        MainNavigationDestination.STORIES -> CameraButton(onClick = { onCameraClick(MainNavigationDestination.STORIES) })
+      }
+    }
+  }
+}
+
+@Composable
+private fun NewChatButton(
+  onClick: () -> Unit
+) {
+  MainFloatingActionButton(
+    onClick = onClick,
+    contentDescription = "",
+    icon = ImageVector.vectorResource(R.drawable.symbol_edit_24)
+  )
+}
+
+@Composable
+private fun CameraButton(
+  onClick: () -> Unit,
+  modifier: Modifier = Modifier,
+  colors: IconButtonColors = IconButtonDefaults.filledTonalIconButtonColors()
+) {
+  MainFloatingActionButton(
+    onClick = onClick,
+    contentDescription = "",
+    icon = ImageVector.vectorResource(R.drawable.symbol_camera_24),
+    colors = colors,
+    modifier = modifier
+  )
+}
+
+@Composable
+private fun NewCallButton(
+  onClick: () -> Unit
+) {
+  MainFloatingActionButton(
+    onClick = onClick,
+    contentDescription = "",
+    icon = ImageVector.vectorResource(R.drawable.symbol_phone_plus_24)
+  )
+}
+
+@Composable
+private fun MainFloatingActionButton(
+  onClick: () -> Unit,
+  icon: ImageVector,
+  contentDescription: String,
+  modifier: Modifier = Modifier,
+  colors: IconButtonColors = IconButtonDefaults.filledTonalIconButtonColors()
+) {
+  FilledTonalIconButton(
+    onClick = onClick,
+    shape = RoundedCornerShape(18.dp),
+    modifier = modifier
+      .size(ACTION_BUTTON_SIZE)
+      .shadow(4.dp, RoundedCornerShape(18.dp)),
+    enabled = true,
+    colors = colors
+  ) {
+    Icon(
+      imageVector = icon,
+      contentDescription = contentDescription
+    )
+  }
+}
+
+@SignalPreview
+@Composable
+private fun MainFloatingActionButtonsPreview() {
+  var destination by remember { mutableStateOf(MainNavigationDestination.CHATS) }
+
+  Previews.Preview {
+    MainFloatingActionButtons(
+      destination = destination,
+      onCameraClick = { destination = MainNavigationDestination.CALLS },
+      onNewChatClick = { destination = MainNavigationDestination.STORIES },
+      onNewCallClick = { destination = MainNavigationDestination.CHATS }
+    )
+  }
+}
+
+@SignalPreview
+@Composable
+private fun NewChatButtonPreview() {
+  Previews.Preview {
+    NewChatButton(
+      onClick = {}
+    )
+  }
+}
+
+@SignalPreview
+@Composable
+private fun CameraButtonPreview() {
+  Previews.Preview {
+    CameraButton(
+      onClick = {}
+    )
+  }
+}
+
+@SignalPreview
+@Composable
+private fun NewCallButtonPreview() {
+  Previews.Preview {
+    NewCallButton(
+      onClick = {}
+    )
+  }
+}

app/src/main/java/org/thoughtcrime/securesms/main/MainMegaphoneContainer.kt

@@ -0,0 +1,111 @@
+/*
+ * Copyright 2025 Signal Messenger, LLC
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+package org.thoughtcrime.securesms.main
+
+import android.app.Activity
+import android.content.Intent
+import android.content.res.Configuration
+import android.view.LayoutInflater
+import android.widget.FrameLayout
+import androidx.compose.animation.AnimatedVisibility
+import androidx.compose.foundation.background
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.height
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.runtime.remember
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.platform.LocalConfiguration
+import androidx.compose.ui.platform.LocalInspectionMode
+import androidx.compose.ui.unit.dp
+import androidx.compose.ui.viewinterop.AndroidView
+import androidx.fragment.app.DialogFragment
+import org.signal.core.ui.compose.Previews
+import org.signal.core.ui.compose.SignalPreview
+import org.thoughtcrime.securesms.R
+import org.thoughtcrime.securesms.megaphone.Megaphone
+import org.thoughtcrime.securesms.megaphone.MegaphoneActionController
+import org.thoughtcrime.securesms.megaphone.MegaphoneViewBuilder
+import org.thoughtcrime.securesms.megaphone.Megaphones
+import org.thoughtcrime.securesms.util.visible
+
+data class MainMegaphoneState(
+  val megaphone: Megaphone = Megaphone.NONE,
+  val isDisplayingArchivedChats: Boolean = false,
+  val isSearchOpen: Boolean = false,
+  val isInActionMode: Boolean = false
+)
+
+object EmptyMegaphoneActionController : MegaphoneActionController {
+  override fun onMegaphoneNavigationRequested(intent: Intent) = Unit
+  override fun onMegaphoneNavigationRequested(intent: Intent, requestCode: Int) = Unit
+  override fun onMegaphoneToastRequested(string: String) = Unit
+  override fun getMegaphoneActivity(): Activity = error("Empty controller")
+  override fun onMegaphoneSnooze(event: Megaphones.Event) = Unit
+  override fun onMegaphoneCompleted(event: Megaphones.Event) = Unit
+  override fun onMegaphoneDialogFragmentRequested(dialogFragment: DialogFragment) = Unit
+}
+
+/**
+ * Composable wrapper for Megaphones
+ */
+@Composable
+fun MainMegaphoneContainer(
+  state: MainMegaphoneState,
+  controller: MegaphoneActionController,
+  onMegaphoneVisible: (Megaphone) -> Unit
+) {
+  val isLandscape = LocalConfiguration.current.orientation == Configuration.ORIENTATION_LANDSCAPE
+  val visible = remember(isLandscape, state.isDisplayingArchivedChats, state.isSearchOpen, state.isInActionMode, state.megaphone) {
+    !(state.megaphone == Megaphone.NONE || state.megaphone.style == Megaphone.Style.FULLSCREEN || state.isDisplayingArchivedChats || isLandscape || state.isSearchOpen || state.isInActionMode)
+  }
+
+  AnimatedVisibility(visible = visible) {
+    if (LocalInspectionMode.current) {
+      Box(
+        modifier = Modifier
+          .background(color = Color.Red)
+          .fillMaxWidth()
+          .height(80.dp)
+      )
+    } else {
+      AndroidView(factory = { context ->
+        LayoutInflater.from(context).inflate(R.layout.conversation_list_megaphone_container, null, false) as FrameLayout
+      }) { megaphoneContainer ->
+        val view = requireNotNull(MegaphoneViewBuilder.build(megaphoneContainer.context, state.megaphone, controller))
+        megaphoneContainer.removeAllViews()
+        megaphoneContainer.addView(view)
+        megaphoneContainer.visible = true
+      }
+    }
+  }
+
+  LaunchedEffect(state.megaphone, state.isDisplayingArchivedChats, isLandscape) {
+    if (state.megaphone == Megaphone.NONE || state.isDisplayingArchivedChats || isLandscape) {
+      return@LaunchedEffect
+    }
+
+    if (state.megaphone.style == Megaphone.Style.FULLSCREEN) {
+      state.megaphone.onVisibleListener?.onEvent(state.megaphone, controller)
+    }
+
+    onMegaphoneVisible(state.megaphone)
+  }
+}
+
+@SignalPreview
+@Composable
+private fun MainMegaphoneContainerPreview() {
+  Previews.Preview {
+    MainMegaphoneContainer(
+      state = MainMegaphoneState(),
+      controller = EmptyMegaphoneActionController,
+      onMegaphoneVisible = {}
+    )
+  }
+}

app/src/main/java/org/thoughtcrime/securesms/megaphone/Megaphone.java

@@ -221,7 +221,7 @@ public class Megaphone {
     }
   }
 
-  enum Style {
+  public enum Style {
     /**
      * Specialized style for onboarding.
      */

core-ui/src/main/java/org/signal/core/ui/compose/Snackbars.kt

@@ -32,7 +32,7 @@ object Snackbars {
   }
 
   @Composable
-  internal fun Default(snackbarData: SnackbarData) {
+  fun Default(snackbarData: SnackbarData) {
     val colors = LocalSnackbarColors.current
     Snackbar(
       snackbarData = snackbarData,