Add initial working E2E flow for MediaSendV3.

app/src/main/AndroidManifest.xml

@@ -482,7 +482,7 @@
             android:windowSoftInputMode="stateAlwaysHidden|adjustNothing" />
 
         <activity
-            android:name="org.signal.mediasend.MediaSendActivity"
+            android:name=".mediasend.v3.MediaSendV3Activity"
             android:configChanges="touchscreen|keyboard|keyboardHidden|orientation|screenLayout|screenSize|uiMode"
             android:exported="false"
             android:launchMode="singleTop"

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

@@ -163,6 +163,7 @@ import org.thoughtcrime.securesms.main.rememberFocusRequester
 import org.thoughtcrime.securesms.main.storiesNavGraphBuilder
 import org.thoughtcrime.securesms.mediasend.camerax.CameraXRemoteConfig
 import org.thoughtcrime.securesms.mediasend.v2.MediaSelectionActivity
+import org.thoughtcrime.securesms.mediasend.v3.mediaSendLauncher
 import org.thoughtcrime.securesms.megaphone.Megaphone
 import org.thoughtcrime.securesms.megaphone.MegaphoneActionController
 import org.thoughtcrime.securesms.megaphone.Megaphones
@@ -271,7 +272,7 @@ class MainActivity :
   override val googlePayRepository: GooglePayRepository by lazy { GooglePayRepository(this) }
   override val googlePayResultPublisher: Subject<GooglePayComponent.GooglePayResult> = PublishSubject.create()
 
-  private lateinit var mediaActivityLauncher: ActivityResultLauncher<MediaSendActivityContract.Args>
+  private lateinit var mediaSendLauncher: ActivityResultLauncher<MediaSendActivityContract.Args>
 
   override fun dispatchTouchEvent(ev: MotionEvent?): Boolean {
     return motionEventRelay.offer(ev) || super.dispatchTouchEvent(ev)
@@ -298,7 +299,7 @@ class MainActivity :
     super.onCreate(savedInstanceState, ready)
     navigator = MainNavigator(this, mainNavigationViewModel)
 
-    mediaActivityLauncher = registerForActivityResult(MediaSendActivityContract()) { }
+    mediaSendLauncher = mediaSendLauncher()
 
     AppForegroundObserver.addListener(object : AppForegroundObserver.Listener {
       override fun onForeground() {
@@ -1124,7 +1125,7 @@ class MainActivity :
       if (isForQuickRestore) {
         startActivity(MediaSelectionActivity.cameraForQuickRestore(context = this@MainActivity))
       } else if (SignalStore.internal.useNewMediaActivity) {
-        mediaActivityLauncher.launch(
+        mediaSendLauncher.launch(
           MediaSendActivityContract.Args(
             isCameraFirst = false,
             isStory = destination == MainNavigationListLocation.STORIES

app/src/main/java/org/thoughtcrime/securesms/mediasend/v3/MediaSendV3Activity.kt

@@ -0,0 +1,40 @@
+/*
+ * Copyright 2026 Signal Messenger, LLC
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+package org.thoughtcrime.securesms.mediasend.v3
+
+import android.os.Bundle
+import androidx.activity.compose.setContent
+import androidx.activity.enableEdgeToEdge
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.ui.Modifier
+import androidx.fragment.compose.AndroidFragment
+import org.signal.mediasend.MediaSendActivityContract
+import org.signal.mediasend.MediaSendScreen
+import org.thoughtcrime.securesms.PassphraseRequiredActivity
+
+/**
+ * Encapsulates the media send flow for v3.
+ */
+class MediaSendV3Activity : PassphraseRequiredActivity() {
+
+  override fun onCreate(savedInstanceState: Bundle?, ready: Boolean) {
+    enableEdgeToEdge()
+
+    val contractArgs = MediaSendActivityContract.Args.fromIntent(intent)
+
+    setContent {
+      MediaSendScreen(
+        contractArgs = contractArgs,
+        sendSlot = {
+          AndroidFragment(
+            clazz = MediaSendV3ForwardFragment::class.java,
+            modifier = Modifier.fillMaxSize()
+          )
+        }
+      )
+    }
+  }
+}

app/src/main/java/org/thoughtcrime/securesms/mediasend/v3/MediaSendV3Extensions.kt

@@ -0,0 +1,29 @@
+/*
+ * Copyright 2026 Signal Messenger, LLC
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+package org.thoughtcrime.securesms.mediasend.v3
+
+import androidx.activity.result.ActivityResultLauncher
+import androidx.activity.result.contract.ActivityResultContract
+import androidx.appcompat.app.AppCompatActivity
+import androidx.fragment.app.Fragment
+import org.signal.mediasend.MediaSendActivityContract
+import org.signal.mediasend.StorySendRequirements
+import org.thoughtcrime.securesms.stories.Stories
+
+private fun contract(): ActivityResultContract<MediaSendActivityContract.Args, MediaSendActivityContract.Result?> = MediaSendActivityContract(MediaSendV3Activity::class.java)
+
+fun Fragment.mediaSendLauncher(callback: (MediaSendActivityContract.Result?) -> Unit = {}): ActivityResultLauncher<MediaSendActivityContract.Args> = registerForActivityResult(contract(), callback)
+
+fun AppCompatActivity.mediaSendLauncher(callback: (MediaSendActivityContract.Result?) -> Unit = {}): ActivityResultLauncher<MediaSendActivityContract.Args> = registerForActivityResult(contract(), callback)
+
+/**
+ * Maps the feature-module [StorySendRequirements] to the app-layer [Stories.MediaTransform.SendRequirements].
+ */
+fun StorySendRequirements.toAppSendRequirements(): Stories.MediaTransform.SendRequirements = when (this) {
+  StorySendRequirements.CAN_SEND -> Stories.MediaTransform.SendRequirements.VALID_DURATION
+  StorySendRequirements.CAN_NOT_SEND -> Stories.MediaTransform.SendRequirements.CAN_NOT_SEND
+  StorySendRequirements.REQUIRES_CROP -> Stories.MediaTransform.SendRequirements.REQUIRES_CLIP
+}

app/src/main/java/org/thoughtcrime/securesms/mediasend/v3/MediaSendV3ForwardFragment.kt

@@ -0,0 +1,115 @@
+/*
+ * Copyright 2026 Signal Messenger, LLC
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+package org.thoughtcrime.securesms.mediasend.v3
+
+import android.os.Bundle
+import android.view.View
+import android.view.ViewGroup
+import androidx.core.content.ContextCompat
+import androidx.fragment.app.Fragment
+import androidx.fragment.app.activityViewModels
+import androidx.lifecycle.lifecycleScope
+import kotlinx.coroutines.launch
+import org.signal.core.util.getParcelableArrayListCompat
+import org.signal.core.util.logging.Log
+import org.signal.mediasend.MediaRecipientId
+import org.signal.mediasend.MediaSendActivityContract
+import org.signal.mediasend.MediaSendState
+import org.signal.mediasend.MediaSendViewModel
+import org.signal.mediasend.SendResult
+import org.thoughtcrime.securesms.R
+import org.thoughtcrime.securesms.contacts.paged.ContactSearchKey
+import org.thoughtcrime.securesms.conversation.mutiselect.forward.MultiselectForwardFragment
+import org.thoughtcrime.securesms.conversation.mutiselect.forward.MultiselectForwardFragmentArgs
+import org.thoughtcrime.securesms.recipients.RecipientId
+import org.thoughtcrime.securesms.safety.SafetyNumberBottomSheet
+import org.thoughtcrime.securesms.stories.Stories
+import org.signal.core.ui.R as CoreUiR
+
+/**
+ * View-backed wrapper around [MultiselectForwardFragment] that provides the [ViewGroup] container
+ * required by [MultiselectForwardFragment.Callback.getContainer] for bottom bar inflation.
+ *
+ * Implements the callback interface and uses the shared [MediaSendViewModel] to drive
+ * the send flow forward.
+ */
+class MediaSendV3ForwardFragment : Fragment(R.layout.multiselect_forward_activity), MultiselectForwardFragment.Callback {
+
+  companion object {
+    private val TAG = Log.tag(MediaSendV3ForwardFragment::class.java)
+  }
+
+  private val viewModel: MediaSendViewModel by activityViewModels {
+    MediaSendViewModel.Factory(args = MediaSendActivityContract.Args.fromIntent(requireActivity().intent))
+  }
+
+  override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
+    super.onViewCreated(view, savedInstanceState)
+
+    if (savedInstanceState == null) {
+      val state = viewModel.state.value
+      val forwardFragment = MultiselectForwardFragment.create(
+        MultiselectForwardFragmentArgs(
+          title = R.string.MediaReviewFragment__send_to,
+          storySendRequirements = state.storySendRequirements.toAppSendRequirements(),
+          isSearchEnabled = !state.isStory,
+          isViewOnce = state.viewOnceToggleState == MediaSendState.ViewOnceToggleState.ONCE
+        )
+      )
+
+      childFragmentManager.beginTransaction()
+        .replace(R.id.fragment_container, forwardFragment)
+        .commitNow()
+    }
+  }
+
+  override fun onFinishForwardAction() = Unit
+
+  override fun exitFlow() {
+    requireActivity().finish()
+  }
+
+  override fun onSearchInputFocused() = Unit
+
+  override fun setResult(bundle: Bundle) {
+    val selectedRecipients: List<ContactSearchKey.RecipientSearchKey> = bundle.getParcelableArrayListCompat(MultiselectForwardFragment.RESULT_SELECTION, ContactSearchKey.RecipientSearchKey::class.java)
+      ?: emptyList()
+
+    val recipientIds = selectedRecipients.map { MediaRecipientId(it.recipientId.toLong()) }
+    viewModel.setAdditionalRecipients(recipientIds)
+
+    viewLifecycleOwner.lifecycleScope.launch {
+      when (val result = viewModel.send()) {
+        is SendResult.Success -> {
+          Log.d(TAG, "Send completed successfully.")
+          requireActivity().finish()
+        }
+        is SendResult.Error -> {
+          Log.w(TAG, "Send failed: ${result.message}")
+          requireActivity().finish()
+        }
+        is SendResult.UntrustedIdentity -> {
+          Log.w(TAG, "Send failed due to untrusted identities.")
+          SafetyNumberBottomSheet
+            .forRecipientIdsAndDestinations(result.recipientIds.map { RecipientId.from(it) }, selectedRecipients)
+            .show(childFragmentManager)
+        }
+      }
+    }
+  }
+
+  override fun getContainer(): ViewGroup {
+    return requireView().findViewById(R.id.fragment_container_wrapper)
+  }
+
+  override fun getDialogBackgroundColor(): Int {
+    return ContextCompat.getColor(requireContext(), CoreUiR.color.signal_colorBackground)
+  }
+
+  override fun getStorySendRequirements(): Stories.MediaTransform.SendRequirements? {
+    return viewModel.getStorySendRequirements().toAppSendRequirements()
+  }
+}

app/src/main/java/org/thoughtcrime/securesms/mediasend/v3/MediaSendV3Repository.kt

@@ -93,9 +93,6 @@ object MediaSendV3Repository : MediaSendRepository {
       return@withContext SendResult.Error("No recipients provided.")
     }
 
-    val singleContact = if (recipients.size == 1) recipients.first() else null
-    val contacts = if (recipients.size > 1) recipients else emptyList()
-
     val legacyEditorStateMap = mapLegacyEditorState(request.editorStateMap)
     val quality = SentMediaQuality.fromCode(request.quality)
 
@@ -106,8 +103,8 @@ object MediaSendV3Repository : MediaSendRepository {
         quality = quality,
         message = request.message,
         isViewOnce = request.isViewOnce,
-        singleContact = singleContact,
-        contacts = contacts,
+        singleContact = null,
+        contacts = recipients,
         mentions = emptyList(),
         bodyRanges = null,
         sendType = resolveSendType(request.sendType),

app/src/main/java/org/thoughtcrime/securesms/safety/SafetyNumberBottomSheet.kt

@@ -122,6 +122,17 @@ object SafetyNumberBottomSheet {
     return SheetFactory(args)
   }
 
+  /**
+   * Create a factory to generate a sheet for the given recipient IDs and destinations.
+   *
+   * @param recipientIds The list of untrusted recipient IDs
+   * @param destinations The list of locations the user was trying to send content
+   */
+  @JvmStatic
+  fun forRecipientIdsAndDestinations(recipientIds: List<RecipientId>, destinations: List<ContactSearchKey.RecipientSearchKey>): Factory {
+    return SheetFactory(SafetyNumberBottomSheetArgs(recipientIds, destinations))
+  }
+
   /**
    * Create a factory to generate a sheet for the given identity records and single destination.
    *

feature/media-send/src/main/java/org/signal/mediasend/MediaSendActivity.kt

@@ -1,77 +0,0 @@
-package org.signal.mediasend
-
-import android.content.Context
-import android.content.Intent
-import android.os.Bundle
-import androidx.activity.compose.setContent
-import androidx.activity.enableEdgeToEdge
-import androidx.activity.viewModels
-import androidx.compose.foundation.layout.fillMaxSize
-import androidx.compose.material3.Surface
-import androidx.compose.runtime.getValue
-import androidx.compose.ui.Modifier
-import androidx.fragment.app.FragmentActivity
-import androidx.lifecycle.compose.collectAsStateWithLifecycle
-import androidx.navigation3.runtime.rememberNavBackStack
-import org.signal.core.ui.compose.theme.SignalTheme
-
-/**
- * Activity for the media sending flow.
- */
-abstract class MediaSendActivity : FragmentActivity() {
-  protected lateinit var contractArgs: MediaSendActivityContract.Args
-    private set
-
-  override fun onCreate(savedInstanceState: Bundle?) {
-    enableEdgeToEdge()
-    super.onCreate(savedInstanceState)
-
-    contractArgs = MediaSendActivityContract.Args.fromIntent(intent)
-
-    setContent {
-      val viewModel by viewModels<MediaSendViewModel>(factoryProducer = {
-        MediaSendViewModel.Factory(
-          args = contractArgs,
-          isMeteredFlow = MeteredConnectivity.isMetered(applicationContext)
-        )
-      })
-
-      val state by viewModel.state.collectAsStateWithLifecycle()
-      val backStack = rememberNavBackStack(
-        if (state.isCameraFirst) MediaSendNavKey.Capture.Camera else MediaSendNavKey.Select
-      )
-
-      SignalTheme {
-        Surface {
-          MediaSendNavDisplay(
-            state = state,
-            backStack = backStack,
-            callback = viewModel,
-            modifier = Modifier.fillMaxSize(),
-            cameraSlot = { },
-            textStoryEditorSlot = { },
-            videoEditorSlot = { },
-            sendSlot = { }
-          )
-        }
-      }
-    }
-  }
-
-  companion object {
-    /**
-     * Creates an intent for [MediaSendActivity].
-     *
-     * @param context The context.
-     * @param args The activity arguments.
-     */
-    fun createIntent(
-      context: Context,
-      args: MediaSendActivityContract.Args = MediaSendActivityContract.Args()
-    ): Intent {
-      return Intent(context, MediaSendActivity::class.java).apply {
-        putExtra(MediaSendActivityContract.EXTRA_ARGS, args)
-      }
-    }
-  }
-}

feature/media-send/src/main/java/org/signal/mediasend/MediaSendActivityContract.kt

@@ -30,7 +30,7 @@ import org.signal.core.models.media.Media
  * class MyMediaSendContract : MediaSendActivityContract(MyMediaSendActivity::class.java)
  * ```
  */
-class MediaSendActivityContract : ActivityResultContract<MediaSendActivityContract.Args, MediaSendActivityContract.Result?>() {
+class MediaSendActivityContract(private val clazz: Class<out Activity>) : ActivityResultContract<MediaSendActivityContract.Args, MediaSendActivityContract.Result?>() {
 
   /**
    * Creates the intent to launch the media send activity.
@@ -38,7 +38,9 @@ class MediaSendActivityContract : ActivityResultContract<MediaSendActivityContra
    * Subclasses should override this if not using the constructor parameter.
    */
   override fun createIntent(context: Context, input: Args): Intent {
-    return MediaSendActivity.createIntent(context, input)
+    return Intent(context, clazz).apply {
+      putExtra(EXTRA_ARGS, input)
+    }
   }
 
   override fun parseResult(resultCode: Int, intent: Intent?): Result? {

feature/media-send/src/main/java/org/signal/mediasend/MediaSendCallback.kt

@@ -21,9 +21,6 @@ interface MediaSendCallback : MediaEditScreenCallback, MediaSelectScreenCallback
   /** Called when the user edits video trim data. */
   fun onVideoEdited(uri: Uri, isEdited: Boolean) {}
 
-  /** Called when message text changes. */
-  fun onMessageChanged(text: CharSequence?) {}
-
   object Empty : MediaSendCallback, MediaEditScreenCallback by MediaEditScreenCallback.Empty, MediaSelectScreenCallback by MediaSelectScreenCallback.Empty {
     override fun setFocusedMedia(media: Media) = Unit
   }

feature/media-send/src/main/java/org/signal/mediasend/MediaSendNavDisplay.kt

@@ -0,0 +1,108 @@
+package org.signal.mediasend
+
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.CompositionLocalProvider
+import androidx.compose.runtime.getValue
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.lifecycle.compose.collectAsStateWithLifecycle
+import androidx.navigation3.runtime.NavBackStack
+import androidx.navigation3.runtime.NavEntry
+import androidx.navigation3.runtime.NavKey
+import androidx.navigation3.runtime.rememberNavBackStack
+import androidx.navigation3.ui.NavDisplay
+import androidx.navigationevent.compose.LocalNavigationEventDispatcherOwner
+import androidx.navigationevent.compose.rememberNavigationEventDispatcherOwner
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.StateFlow
+import org.signal.core.ui.compose.AllDevicePreviews
+import org.signal.core.ui.compose.Previews
+import org.signal.mediasend.edit.MediaEditScreen
+import org.signal.mediasend.select.MediaSelectScreen
+
+/**
+ * Enforces the following flow of:
+ *
+ * Capture -> Edit -> Send
+ * Select -> Edit -> Send
+ */
+@Composable
+fun MediaSendNavDisplay(
+  stateFlow: StateFlow<MediaSendState>,
+  backStack: NavBackStack<NavKey>,
+  callback: MediaSendCallback,
+  modifier: Modifier = Modifier,
+  cameraSlot: @Composable () -> Unit = {},
+  textStoryEditorSlot: @Composable () -> Unit = {},
+  videoEditorSlot: @Composable () -> Unit = {},
+  sendSlot: @Composable (MediaSendState) -> Unit = {}
+) {
+  NavDisplay(
+    backStack = backStack,
+    modifier = modifier.fillMaxSize()
+  ) { key ->
+    when (key) {
+      is MediaSendNavKey.Capture -> NavEntry(MediaSendNavKey.Capture.Chrome) {
+        MediaCaptureScreen(
+          backStack = backStack,
+          cameraSlot = cameraSlot,
+          textStoryEditorSlot = textStoryEditorSlot
+        )
+      }
+
+      MediaSendNavKey.Select -> NavEntry(key) {
+        val state by stateFlow.collectAsStateWithLifecycle()
+        MediaSelectScreen(
+          state = state,
+          backStack = backStack,
+          callback = callback
+        )
+      }
+
+      is MediaSendNavKey.Edit -> NavEntry(MediaSendNavKey.Edit) {
+        val state by stateFlow.collectAsStateWithLifecycle()
+        MediaEditScreen(
+          state = state,
+          backStack = backStack,
+          videoEditorSlot = videoEditorSlot,
+          callback = callback
+        )
+      }
+
+      is MediaSendNavKey.Send -> NavEntry(key) {
+        val state by stateFlow.collectAsStateWithLifecycle()
+        sendSlot(state)
+      }
+
+      else -> error("Unknown key: $key")
+    }
+  }
+}
+
+@AllDevicePreviews
+@Composable
+private fun MediaSendNavDisplayPreview() {
+  Previews.Preview {
+    CompositionLocalProvider(LocalNavigationEventDispatcherOwner provides rememberNavigationEventDispatcherOwner(parent = null)) {
+      MediaSendNavDisplay(
+        stateFlow = MutableStateFlow(MediaSendState(isCameraFirst = true)),
+        backStack = rememberNavBackStack(MediaSendNavKey.Edit),
+        callback = MediaSendCallback.Empty,
+        cameraSlot = { BoxWithText("Camera Slot") },
+        textStoryEditorSlot = { BoxWithText("Text Story Editor Slot") },
+        videoEditorSlot = { BoxWithText("Video Editor Slot") },
+        sendSlot = { _ -> BoxWithText("Send Slot") }
+      )
+    }
+  }
+}
+
+@Composable
+private fun BoxWithText(text: String, modifier: Modifier = Modifier) {
+  Box(modifier = modifier.fillMaxSize(), contentAlignment = Alignment.Center) {
+    Text(text = text)
+  }
+}

feature/media-send/src/main/java/org/signal/mediasend/MediaSendScreen.kt

@@ -1,101 +1,53 @@
+/*
+ * Copyright 2026 Signal Messenger, LLC
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
 package org.signal.mediasend
 
-import androidx.compose.foundation.layout.Box
-import androidx.compose.foundation.layout.fillMaxSize
-import androidx.compose.material3.Text
+import androidx.activity.compose.LocalActivity
+import androidx.compose.material3.Surface
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.CompositionLocalProvider
-import androidx.compose.ui.Alignment
+import androidx.compose.runtime.getValue
 import androidx.compose.ui.Modifier
-import androidx.navigation3.runtime.NavBackStack
-import androidx.navigation3.runtime.NavEntry
-import androidx.navigation3.runtime.NavKey
+import androidx.lifecycle.compose.collectAsStateWithLifecycle
+import androidx.lifecycle.viewmodel.compose.viewModel
 import androidx.navigation3.runtime.rememberNavBackStack
-import androidx.navigation3.ui.NavDisplay
+import androidx.navigationevent.NavigationEventDispatcherOwner
 import androidx.navigationevent.compose.LocalNavigationEventDispatcherOwner
-import androidx.navigationevent.compose.rememberNavigationEventDispatcherOwner
-import org.signal.core.ui.compose.AllDevicePreviews
-import org.signal.core.ui.compose.Previews
-import org.signal.mediasend.edit.MediaEditScreen
-import org.signal.mediasend.select.MediaSelectScreen
+import org.signal.core.ui.compose.theme.SignalTheme
 
-/**
- * Enforces the following flow of:
- *
- * Capture -> Edit -> Send
- * Select -> Edit -> Send
- */
 @Composable
-fun MediaSendNavDisplay(
-  state: MediaSendState,
-  backStack: NavBackStack<NavKey>,
-  callback: MediaSendCallback,
+fun MediaSendScreen(
+  contractArgs: MediaSendActivityContract.Args,
   modifier: Modifier = Modifier,
   cameraSlot: @Composable () -> Unit = {},
   textStoryEditorSlot: @Composable () -> Unit = {},
   videoEditorSlot: @Composable () -> Unit = {},
-  sendSlot: @Composable () -> Unit = {}
+  sendSlot: @Composable (MediaSendState) -> Unit = {}
 ) {
-  NavDisplay(
-    backStack = backStack,
-    modifier = modifier.fillMaxSize()
-  ) { key ->
-    when (key) {
-      is MediaSendNavKey.Capture -> NavEntry(MediaSendNavKey.Capture.Chrome) {
-        MediaCaptureScreen(
+  val viewModel = viewModel<MediaSendViewModel>(factory = MediaSendViewModel.Factory(args = contractArgs))
+
+  val state by viewModel.state.collectAsStateWithLifecycle()
+  val backStack = rememberNavBackStack(
+    if (state.isCameraFirst) MediaSendNavKey.Capture.Camera else MediaSendNavKey.Select
+  )
+
+  SignalTheme {
+    CompositionLocalProvider(LocalNavigationEventDispatcherOwner provides LocalActivity.current as NavigationEventDispatcherOwner) {
+      Surface {
+        MediaSendNavDisplay(
+          stateFlow = viewModel.state,
           backStack = backStack,
+          callback = viewModel,
+          modifier = modifier,
           cameraSlot = cameraSlot,
-          textStoryEditorSlot = textStoryEditorSlot
-        )
-      }
-
-      MediaSendNavKey.Select -> NavEntry(key) {
-        MediaSelectScreen(
-          state = state,
-          backStack = backStack,
-          callback = callback
-        )
-      }
-
-      is MediaSendNavKey.Edit -> NavEntry(MediaSendNavKey.Edit) {
-        MediaEditScreen(
-          state = state,
-          backStack = backStack,
+          textStoryEditorSlot = textStoryEditorSlot,
           videoEditorSlot = videoEditorSlot,
-          callback = callback
+          sendSlot = sendSlot
         )
       }
-
-      is MediaSendNavKey.Send -> NavEntry(key) {
-        sendSlot()
-      }
-
-      else -> error("Unknown key: $key")
     }
   }
 }
-
-@AllDevicePreviews
-@Composable
-private fun MediaSendNavDisplayPreview() {
-  Previews.Preview {
-    CompositionLocalProvider(LocalNavigationEventDispatcherOwner provides rememberNavigationEventDispatcherOwner(parent = null)) {
-      MediaSendNavDisplay(
-        state = MediaSendState(isCameraFirst = true),
-        backStack = rememberNavBackStack(MediaSendNavKey.Edit),
-        callback = MediaSendCallback.Empty,
-        cameraSlot = { BoxWithText("Camera Slot") },
-        textStoryEditorSlot = { BoxWithText("Text Story Editor Slot") },
-        videoEditorSlot = { BoxWithText("Video Editor Slot") },
-        sendSlot = { BoxWithText("Send Slot") }
-      )
-    }
-  }
-}
-
-@Composable
-private fun BoxWithText(text: String, modifier: Modifier = Modifier) {
-  Box(modifier = modifier.fillMaxSize(), contentAlignment = Alignment.Center) {
-    Text(text = text)
-  }
-}

feature/media-send/src/main/java/org/signal/mediasend/MediaSendViewModel.kt

@@ -48,14 +48,18 @@ import kotlin.time.Duration.Companion.milliseconds
  * [MediaSendState] is fully [Parcelable] and saved directly as a single key.
  */
 class MediaSendViewModel(
-  private val args: MediaSendActivityContract.Args,
-  private val identityChangesSince: Long,
-  isMeteredFlow: Flow<Boolean>,
   private val savedStateHandle: SavedStateHandle,
   private val repository: MediaSendRepository,
-  private val preUploadController: PreUploadController
+  private val preUploadController: PreUploadController,
+  isMeteredFlow: Flow<Boolean>
 ) : ViewModel(), MediaSendCallback {
 
+  private val args: MediaSendActivityContract.Args = savedStateHandle[KEY_ARGS]
+    ?: throw IllegalStateException("MediaSendViewModel requires args in SavedStateHandle. Use Factory to create.")
+
+  private val identityChangesSince: Long = savedStateHandle[KEY_IDENTITY_CHANGES_SINCE]
+    ?: throw IllegalStateException("MediaSendViewModel requires identityChangesSince in SavedStateHandle. Use Factory to create.")
+
   private val defaultState = MediaSendState(
     isCameraFirst = args.isCameraFirst,
     recipientId = args.recipientId,
@@ -138,7 +142,7 @@ class MediaSendViewModel(
         it.copy(
           mediaFolders = folders,
           selectedMediaFolder = if (it.selectedMediaFolder in folders) it.selectedMediaFolder else null,
-          selectedMedia = if (it.selectedMediaFolder in folders) it.selectedMediaFolderItems else emptyList()
+          selectedMediaFolderItems = if (it.selectedMediaFolder in folders) it.selectedMediaFolderItems else emptyList()
         )
       }
     }
@@ -568,8 +572,8 @@ class MediaSendViewModel(
     updateState { copy(message = text) }
   }
 
-  override fun onMessageChanged(text: CharSequence?) {
-    setMessage(text?.toString())
+  override fun onMessageChange(message: String) {
+    setMessage(message)
   }
 
   //endregion
@@ -711,33 +715,43 @@ class MediaSendViewModel(
 
   //endregion
 
-  //region Factory
+  companion object {
+    private const val KEY_ARGS = "media_send_vm_args"
+    private const val KEY_IDENTITY_CHANGES_SINCE = "media_send_vm_identity_changes_since"
+    private const val KEY_STATE = "media_send_vm_state"
+    private const val KEY_EDITED_VIDEO_URIS = "media_send_vm_edited_video_uris"
+  }
 
+  /**
+   * Factory that creates [MediaSendViewModel] from a [SavedStateHandle] and static dependencies.
+   *
+   * On first creation, [args] and [identityChangesSince] are written into the [SavedStateHandle].
+   * On process death restoration, the [SavedStateHandle] already contains the persisted values
+   * and the constructor parameters are ignored.
+   */
   class Factory(
     private val args: MediaSendActivityContract.Args,
     private val identityChangesSince: Long = System.currentTimeMillis(),
-    private val isMeteredFlow: Flow<Boolean>
+    private val repository: MediaSendRepository = MediaSendDependencies.mediaSendRepository,
+    private val isMeteredFlow: Flow<Boolean> = MeteredConnectivity.isMetered(MediaSendDependencies.application)
   ) : ViewModelProvider.Factory {
-
     @Suppress("UNCHECKED_CAST")
     override fun <T : ViewModel> create(modelClass: Class<T>, extras: CreationExtras): T {
       val savedStateHandle = extras.createSavedStateHandle()
 
+      if (!savedStateHandle.contains(KEY_ARGS)) {
+        savedStateHandle[KEY_ARGS] = args
+      }
+      if (!savedStateHandle.contains(KEY_IDENTITY_CHANGES_SINCE)) {
+        savedStateHandle[KEY_IDENTITY_CHANGES_SINCE] = identityChangesSince
+      }
+
       return MediaSendViewModel(
-        args = args,
-        identityChangesSince = identityChangesSince,
-        isMeteredFlow = isMeteredFlow,
         savedStateHandle = savedStateHandle,
-        repository = MediaSendDependencies.mediaSendRepository,
-        preUploadController = PreUploadController()
+        repository = repository,
+        preUploadController = PreUploadController(),
+        isMeteredFlow = isMeteredFlow
       ) as T
     }
   }
-
-  //endregion
-
-  companion object {
-    private const val KEY_STATE = "media_send_vm_state"
-    private const val KEY_EDITED_VIDEO_URIS = "media_send_vm_edited_video_uris"
-  }
 }

feature/media-send/src/main/java/org/signal/mediasend/NavBackStackExtensions.kt

@@ -16,6 +16,14 @@ internal fun NavBackStack<NavKey>.goToEdit() {
   }
 }
 
+internal fun NavBackStack<NavKey>.goToSend() {
+  if (contains(MediaSendNavKey.Send)) {
+    popTo(MediaSendNavKey.Send)
+  } else {
+    add(MediaSendNavKey.Send)
+  }
+}
+
 internal fun NavBackStack<NavKey>.pop() {
   if (isNotEmpty()) {
     removeAt(size - 1)

feature/media-send/src/main/java/org/signal/mediasend/edit/AddAMessageRow.kt

@@ -29,10 +29,12 @@ import org.signal.core.ui.compose.SignalIcons
 import org.signal.core.util.isNotNullOrBlank
 
 @Composable
-internal fun AddAMessageRow(
+fun AddAMessageRow(
   message: String?,
   callback: AddAMessageRowCallback,
-  modifier: Modifier = Modifier
+  onNextClick: () -> Unit,
+  modifier: Modifier = Modifier,
+  onEmojiKeyboardClick: () -> Unit = {}
 ) {
   Row(
     horizontalArrangement = Arrangement.Center,
@@ -47,7 +49,7 @@ internal fun AddAMessageRow(
         .heightIn(min = 40.dp)
     ) {
       IconButtons.IconButton(
-        onClick = callback::onEmojiKeyboardClick
+        onClick = onEmojiKeyboardClick
       ) {
         Icon(
           painter = SignalIcons.Emoji.painter,
@@ -74,7 +76,7 @@ internal fun AddAMessageRow(
     }
 
     IconButtons.IconButton(
-      onClick = callback::onNextClick,
+      onClick = onNextClick,
       modifier = Modifier
         .padding(start = 12.dp)
         .background(
@@ -99,19 +101,16 @@ private fun AddAMessageRowPreview() {
   Previews.Preview {
     AddAMessageRow(
       message = null,
-      callback = AddAMessageRowCallback.Empty
+      callback = AddAMessageRowCallback.Empty,
+      onNextClick = {}
     )
   }
 }
 
-internal interface AddAMessageRowCallback {
+interface AddAMessageRowCallback {
   fun onMessageChange(message: String)
-  fun onEmojiKeyboardClick()
-  fun onNextClick()
 
   object Empty : AddAMessageRowCallback {
     override fun onMessageChange(message: String) = Unit
-    override fun onEmojiKeyboardClick() = Unit
-    override fun onNextClick() = Unit
   }
 }

feature/media-send/src/main/java/org/signal/mediasend/edit/MediaEditScreen.kt

@@ -37,6 +37,7 @@ import org.signal.core.util.ContentTypeUtil
 import org.signal.mediasend.EditorState
 import org.signal.mediasend.MediaSendNavKey
 import org.signal.mediasend.MediaSendState
+import org.signal.mediasend.goToSend
 
 @Composable
 fun MediaEditScreen(
@@ -111,7 +112,8 @@ fun MediaEditScreen(
 
       AddAMessageRow(
         message = state.message,
-        callback = AddAMessageRowCallback.Empty,
+        callback = callback,
+        onNextClick = { backStack.goToSend() },
         modifier = Modifier
           .widthIn(max = 624.dp)
           .padding(horizontal = 16.dp)
@@ -145,10 +147,10 @@ private fun MediaEditScreenPreview() {
   }
 }
 
-interface MediaEditScreenCallback {
+interface MediaEditScreenCallback : AddAMessageRowCallback {
   fun setFocusedMedia(media: Media)
 
-  object Empty : MediaEditScreenCallback {
+  object Empty : MediaEditScreenCallback, AddAMessageRowCallback by AddAMessageRowCallback.Empty {
     override fun setFocusedMedia(media: Media) = Unit
   }
 }

feature/media-send/src/main/java/org/signal/mediasend/select/MediaSelectScreen.kt

@@ -23,6 +23,7 @@ import androidx.compose.foundation.layout.Column
 import androidx.compose.foundation.layout.PaddingValues
 import androidx.compose.foundation.layout.Row
 import androidx.compose.foundation.layout.aspectRatio
+import androidx.compose.foundation.layout.fillMaxSize
 import androidx.compose.foundation.layout.fillMaxWidth
 import androidx.compose.foundation.layout.padding
 import androidx.compose.foundation.layout.size
@@ -99,7 +100,9 @@ internal fun MediaSelectScreen(
     }
   ) { paddingValues ->
     Column(
-      modifier = Modifier.padding(paddingValues)
+      modifier = Modifier
+        .padding(paddingValues)
+        .fillMaxSize()
     ) {
       LazyVerticalGrid(
         columns = gridConfiguration.gridCells,