Migrate recent media rail to compose.

2026-09-13 12:07:57 +01:00 · 2026-08-17 14:36:14 -04:00
parent a20c7f70cb
commit cb8bcba86b
31 changed files with 666 additions and 455 deletions
@@ -683,30 +683,33 @@ dependencies {
  ktlintRuleset(libs.ktlint.twitter.compose)
  coreLibraryDesugaring(libs.android.tools.desugar)

-  implementation(project(":lib:archive"))
-  implementation(project(":lib:libsignal-service"))
-  implementation(project(":lib:network"))
-  implementation(project(":lib:paging"))
-  implementation(project(":core:util"))
-  implementation(project(":lib:glide"))
-  implementation(project(":lib:video"))
-  implementation(project(":lib:device-transfer"))
-  implementation(project(":lib:image-editor"))
-  implementation(project(":lib:donations"))
-  implementation(project(":lib:debuglogs-viewer"))
-  implementation(project(":lib:contacts"))
-  implementation(project(":lib:qr"))
-  implementation(project(":lib:sticky-header-grid"))
-  implementation(project(":lib:photoview"))
-  implementation(project(":lib:blurhash"))
-  implementation(project(":core:ui"))
  implementation(project(":core:models"))
  implementation(project(":core:models-jvm"))
  implementation(project(":core:serialization"))
+  implementation(project(":core:ui"))
+  implementation(project(":core:util"))
+
+  implementation(project(":lib:apng"))
+  implementation(project(":lib:archive"))
+  implementation(project(":lib:contacts"))
+  implementation(project(":lib:blurhash"))
+  implementation(project(":lib:debuglogs-viewer"))
+  implementation(project(":lib:device-transfer"))
+  implementation(project(":lib:donations"))
+  implementation(project(":lib:emoji"))
+  implementation(project(":lib:glide"))
+  implementation(project(":lib:image-editor"))
+  implementation(project(":lib:libsignal-service"))
+  implementation(project(":lib:network"))
+  implementation(project(":lib:paging"))
+  implementation(project(":lib:photoview"))
+  implementation(project(":lib:qr"))
+  implementation(project(":lib:sticky-header-grid"))
+  implementation(project(":lib:ui-components"))
+  implementation(project(":lib:video"))
+
  implementation(project(":feature:camera"))
  implementation(project(":feature:registration"))
-  implementation(project(":lib:apng"))
-  implementation(project(":lib:emoji"))

  implementation(libs.androidx.fragment.ktx)
  implementation(libs.androidx.appcompat)
@@ -1,132 +0,0 @@
-package org.thoughtcrime.securesms.components;
-
-
-import android.content.Context;
-import android.util.AttributeSet;
-import android.view.LayoutInflater;
-import android.view.View;
-import android.view.ViewGroup;
-import android.widget.FrameLayout;
-
-import androidx.annotation.NonNull;
-import androidx.annotation.Nullable;
-import androidx.recyclerview.widget.DefaultItemAnimator;
-import androidx.recyclerview.widget.LinearLayoutManager;
-import androidx.recyclerview.widget.RecyclerView;
-
-import com.bumptech.glide.RequestManager;
-
-import org.signal.core.util.logging.Log;
-import org.thoughtcrime.securesms.R;
-import org.thoughtcrime.securesms.database.MediaTable;
-import org.thoughtcrime.securesms.mediapreview.MediaPreviewCache;
-import org.thoughtcrime.securesms.mms.Slide;
-import org.thoughtcrime.securesms.util.MediaUtil;
-
-import java.util.ArrayList;
-import java.util.List;
-
-public class ThreadPhotoRailView extends FrameLayout {
-
-  @NonNull  private final RecyclerView          recyclerView;
-  @Nullable private       OnItemClickedListener listener;
-
-  public ThreadPhotoRailView(Context context) {
-    this(context, null);
-  }
-
-  public ThreadPhotoRailView(Context context, AttributeSet attrs) {
-    this(context, attrs, 0);
-  }
-
-  public ThreadPhotoRailView(Context context, AttributeSet attrs, int defStyleAttr) {
-    super(context, attrs, defStyleAttr);
-
-    inflate(context, R.layout.recipient_preference_photo_rail, this);
-
-    this.recyclerView = findViewById(R.id.photo_list);
-    this.recyclerView.setLayoutManager(new LinearLayoutManager(context, LinearLayoutManager.HORIZONTAL, false));
-    this.recyclerView.setItemAnimator(new DefaultItemAnimator());
-    this.recyclerView.setNestedScrollingEnabled(false);
-  }
-
-  public void setListener(@Nullable OnItemClickedListener listener) {
-    this.listener = listener;
-
-    if (this.recyclerView.getAdapter() != null) {
-      ((ThreadPhotoRailAdapter)this.recyclerView.getAdapter()).setListener(listener);
-    }
-  }
-
-  public void setMediaRecords(@NonNull RequestManager requestManager, @NonNull List<MediaTable.MediaRecord> mediaRecords) {
-    this.recyclerView.setAdapter(new ThreadPhotoRailAdapter(getContext(), requestManager, mediaRecords, this.listener));
-  }
-
-  private static class ThreadPhotoRailAdapter extends RecyclerView.Adapter<ThreadPhotoRailAdapter.ThreadPhotoViewHolder> {
-
-    @SuppressWarnings("unused")
-    private static final String TAG = Log.tag(ThreadPhotoRailAdapter.class);
-
-    @NonNull  private final RequestManager requestManager;
-
-    @Nullable private OnItemClickedListener clickedListener;
-
-    private final List<MediaTable.MediaRecord> mediaRecords = new ArrayList<>();
-
-    private ThreadPhotoRailAdapter(@NonNull Context context,
-                                   @NonNull RequestManager requestManager,
-                                   @NonNull List<MediaTable.MediaRecord> mediaRecords,
-                                   @Nullable OnItemClickedListener listener)
-    {
-      this.requestManager  = requestManager;
-      this.clickedListener = listener;
-
-      this.mediaRecords.clear();
-      this.mediaRecords.addAll(mediaRecords);
-    }
-
-    @Override
-    public int getItemCount() {
-      return mediaRecords.size();
-    }
-
-    @Override
-    public @NonNull ThreadPhotoViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
-      View itemView = LayoutInflater.from(parent.getContext())
-                                    .inflate(R.layout.recipient_preference_photo_rail_item, parent, false);
-
-      return new ThreadPhotoViewHolder(itemView);
-    }
-
-    @Override
-    public void onBindViewHolder(@NonNull ThreadPhotoViewHolder viewHolder, int position) {
-      MediaTable.MediaRecord mediaRecord = mediaRecords.get(position);
-      Slide                  slide       = MediaUtil.getSlideForAttachment(mediaRecord.getAttachment());
-
-      viewHolder.imageView.setImageResource(requestManager, slide, false, false);
-      viewHolder.imageView.setOnClickListener(v -> {
-        MediaPreviewCache.INSTANCE.setDrawable(viewHolder.imageView.getImageDrawable());
-        if (clickedListener != null) clickedListener.onItemClicked(viewHolder.imageView, mediaRecord);
-      });
-    }
-
-    public void setListener(@Nullable OnItemClickedListener listener) {
-      this.clickedListener = listener;
-    }
-
-    static class ThreadPhotoViewHolder extends RecyclerView.ViewHolder {
-
-      ThumbnailView imageView;
-
-      ThreadPhotoViewHolder(View itemView) {
-        super(itemView);
-
-        this.imageView = itemView.findViewById(R.id.thumbnail);
-      }
-    }
-  }
-
-  public interface OnItemClickedListener {
-    void onItemClicked(View itemView, MediaTable.MediaRecord mediaRecord);
-  }
-}
@@ -5,6 +5,7 @@

 package org.thoughtcrime.securesms.components.settings.conversation

+import androidx.compose.ui.unit.IntRect
 import org.thoughtcrime.securesms.badges.models.Badge
 import org.thoughtcrime.securesms.database.MediaTable
 import org.thoughtcrime.securesms.database.model.IdentityRecord
@@ -105,8 +106,8 @@ sealed interface ConversationSettingsAction {
    override fun toString(): String = "ShowSafetyNumber(hasIdentityRecord=${identityRecord != null})"
  }

-  /** Open the media viewer on the item the user tapped in the shared media rail. */
-  data class ShowMediaPreview(val mediaRecord: MediaTable.MediaRecord, val isLtr: Boolean) : ConversationSettingsAction {
+  /** Open the media viewer on the item the user tapped in the shared media rail, scaling up out of [bounds]. */
+  data class ShowMediaPreview(val mediaRecord: MediaTable.MediaRecord, val isLtr: Boolean, val bounds: IntRect) : ConversationSettingsAction {
    override fun toString(): String = "ShowMediaPreview(messageId=${mediaRecord.messageId}, isLtr=$isLtr)"
  }

@@ -17,6 +17,7 @@ import androidx.activity.result.ActivityResultLauncher
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.LaunchedEffect
 import androidx.compose.runtime.getValue
+import androidx.compose.ui.unit.IntRect
 import androidx.core.view.doOnPreDraw
 import androidx.fragment.app.viewModels
 import androidx.lifecycle.compose.collectAsStateWithLifecycle
@@ -30,6 +31,7 @@ import org.signal.core.util.getParcelableArrayListExtraCompat
 import org.signal.core.util.logging.Log
 import org.signal.core.util.requireParcelableCompat
 import org.signal.donations.InAppPaymentType
+import org.signal.uicomponents.recentmediarail.RecentMediaRailEvents
 import org.thoughtcrime.securesms.AvatarPreviewActivity
 import org.thoughtcrime.securesms.BlockUnblockDialog
 import org.thoughtcrime.securesms.MainActivity
@@ -66,6 +68,7 @@ import org.thoughtcrime.securesms.main.MainNavigationChatDetailRouter
 import org.thoughtcrime.securesms.main.MainNavigationDetailLocation
 import org.thoughtcrime.securesms.mediaoverview.MediaOverviewActivity
 import org.thoughtcrime.securesms.mediapreview.MediaIntentFactory
+import org.thoughtcrime.securesms.mediapreview.MediaPreviewCache
 import org.thoughtcrime.securesms.nicknames.NicknameActivity
 import org.thoughtcrime.securesms.profiles.edit.CreateProfileActivity
 import org.thoughtcrime.securesms.recipients.RecipientExporter
@@ -117,9 +120,8 @@ class ConversationSettingsFragment : ComposeFragment() {
  private var transitionCallback: TransitionCallback? = null
  private var chatRouter: MainNavigationChatDetailRouter? = null

-  /** The avatar and shared media views own the shared element transitions out of this screen. */
+  /** The avatar view owns the shared element transition out of this screen. */
  private var avatarView: View? = null
-  private var lastClickedSharedMediaView: View? = null

  private lateinit var addToGroupStoryDelegate: AddToGroupStoryDelegate
  private lateinit var nicknameLauncher: ActivityResultLauncher<NicknameActivity.Args>
@@ -163,7 +165,6 @@ class ConversationSettingsFragment : ComposeFragment() {
  override fun onDestroyView() {
    super.onDestroyView()
    avatarView = null
-    lastClickedSharedMediaView = null
  }

  /**
@@ -202,8 +203,7 @@ class ConversationSettingsFragment : ComposeFragment() {
      state = state,
      onEvent = individualViewModel::onEvent,
      onNavigationClick = { requireActivity().onBackPressedDispatcher.onBackPressed() },
-      onAvatarViewCreated = { avatarView = it },
-      onSharedMediaViewClicked = { lastClickedSharedMediaView = it }
+      onAvatarViewCreated = { avatarView = it }
    )
  }

@@ -218,8 +218,7 @@ class ConversationSettingsFragment : ComposeFragment() {
      state = state,
      onEvent = individualViewModel::onEvent,
      onNavigationClick = { requireActivity().onBackPressedDispatcher.onBackPressed() },
-      onAvatarViewCreated = { avatarView = it },
-      onSharedMediaViewClicked = { lastClickedSharedMediaView = it }
+      onAvatarViewCreated = { avatarView = it }
    )
  }

@@ -234,8 +233,7 @@ class ConversationSettingsFragment : ComposeFragment() {
      state = state,
      onEvent = individualViewModel::onEvent,
      onNavigationClick = { requireActivity().onBackPressedDispatcher.onBackPressed() },
-      onAvatarViewCreated = { avatarView = it },
-      onSharedMediaViewClicked = { lastClickedSharedMediaView = it }
+      onAvatarViewCreated = { avatarView = it }
    )
  }

@@ -250,11 +248,25 @@ class ConversationSettingsFragment : ComposeFragment() {
      state = state,
      onEvent = groupViewModel::onEvent,
      onNavigationClick = { requireActivity().onBackPressedDispatcher.onBackPressed() },
-      onAvatarViewCreated = { avatarView = it },
-      onSharedMediaViewClicked = { lastClickedSharedMediaView = it }
+      onAvatarViewCreated = { avatarView = it }
    )
  }

+  /**
+   * Animates the media viewer up out of the rail item the user tapped. [bounds] arrive in window coordinates, since the
+   * rail is Compose and has no view of its own to hand over, so they have to be moved into our root view's space first.
+   */
+  private fun scaleUpFromRail(bounds: IntRect): ActivityOptions? {
+    if (bounds.isEmpty) {
+      return null
+    }
+
+    val root = view ?: return null
+    val rootLocation = IntArray(2).also { root.getLocationInWindow(it) }
+
+    return ActivityOptions.makeScaleUpAnimation(root, bounds.left - rootLocation[0], bounds.top - rootLocation[1], bounds.width, bounds.height)
+  }
+
  @Composable
  private fun NotifyWhenLoaded(isLoaded: Boolean) {
    LaunchedEffect(isLoaded) {
@@ -277,8 +289,8 @@ class ConversationSettingsFragment : ComposeFragment() {
      }
      REQUEST_CODE_RETURN_FROM_MEDIA -> {
        dispatch(
-          individual = { it.onEvent(IndividualSettingsEvent.SharedMediaRefreshRequested) },
-          group = { it.onEvent(GroupSettingsEvent.SharedMediaRefreshRequested) }
+          individual = { it.onEvent(IndividualSettingsEvent.MediaRailEvent(RecentMediaRailEvents.RefreshRequested)) },
+          group = { it.onEvent(GroupSettingsEvent.MediaRailEvent(RecentMediaRailEvents.RefreshRequested)) }
        )
      }
      REQUEST_CODE_ADD_CONTACT, REQUEST_CODE_VIEW_CONTACT -> {
@@ -414,21 +426,15 @@ class ConversationSettingsFragment : ComposeFragment() {
        VerifyIdentityActivity.startOrShowExchangeMessagesDialog(requireActivity(), action.identityRecord)
      }
      is ConversationSettingsAction.ShowMediaPreview -> {
-        val view = lastClickedSharedMediaView
-        if (view != null) {
-          view.transitionName = "thumb"
-          val options = ActivityOptions.makeSceneTransitionAnimation(requireActivity(), view, "thumb")
-          startActivityForResult(
-            MediaIntentFactory.intentFromMediaRecord(requireContext(), action.mediaRecord, action.isLtr, allMediaInRail = true),
-            REQUEST_CODE_RETURN_FROM_MEDIA,
-            options.toBundle()
-          )
-        } else {
-          startActivityForResult(
-            MediaIntentFactory.intentFromMediaRecord(requireContext(), action.mediaRecord, action.isLtr, allMediaInRail = true),
-            REQUEST_CODE_RETURN_FROM_MEDIA
-          )
-        }
+        // The rail is Compose and has no drawable to hand over, so make sure the viewer doesn't try to transition out of
+        // whatever some other screen left behind.
+        MediaPreviewCache.drawable = null
+
+        startActivityForResult(
+          MediaIntentFactory.intentFromMediaRecord(requireContext(), action.mediaRecord, action.isLtr, allMediaInRail = true),
+          REQUEST_CODE_RETURN_FROM_MEDIA,
+          scaleUpFromRail(action.bounds)?.toBundle()
+        )
      }
      is ConversationSettingsAction.DownloadMedia -> {
        action.mediaRecord.attachment?.let { AttachmentDownloadJob.downloadAttachmentIfNeeded(it) }
@@ -5,9 +5,11 @@

 package org.thoughtcrime.securesms.components.settings.conversation.group

+import org.signal.uicomponents.recentmediarail.RecentMediaRailAction
+import org.signal.uicomponents.recentmediarail.RecentMediaRailEvents
+import org.signal.uicomponents.recentmediarail.RecentMediaRailState
 import org.thoughtcrime.securesms.components.settings.conversation.ConversationSettingsRepository.GroupDetails
 import org.thoughtcrime.securesms.components.settings.conversation.shared.CallEntry
-import org.thoughtcrime.securesms.database.MediaTable
 import org.thoughtcrime.securesms.database.model.StoryViewState
 import org.thoughtcrime.securesms.groups.memberlabel.StyledMemberLabel
 import org.thoughtcrime.securesms.recipients.RecipientId
@@ -74,14 +76,6 @@ sealed interface GroupSettingsEvent {
  /** The user tapped the starred messages row. */
  data object StarredMessagesClicked : GroupSettingsEvent

-  /** The user tapped an item in the shared media rail, carrying the media that item stands for. */
-  data class SharedMediaClicked(val mediaRecord: MediaTable.MediaRecord, val isLtr: Boolean) : GroupSettingsEvent {
-    override fun toString(): String = "SharedMediaClicked(messageId=${mediaRecord.messageId}, isLtr=$isLtr)"
-  }
-
-  /** The user tapped "see all" on the shared media rail, which opens the media overview. */
-  data object SeeAllSharedMediaClicked : GroupSettingsEvent
-
  /** The user tapped the search button in the member list header. */
  data object MemberSearchClicked : GroupSettingsEvent

@@ -150,9 +144,6 @@ sealed interface GroupSettingsEvent {
    override fun toString(): String = "AddMembersSelected(count=${recipientIds.size})"
  }

-  /** The user came back from the media viewer, so the shared media rail may be out of date. */
-  data object SharedMediaRefreshRequested : GroupSettingsEvent
-
  /** The group's record or recipient changed, alongside whether its chat is currently archived. */
  data class GroupDetailsChanged(val details: GroupDetails, val isArchived: Boolean) : GroupSettingsEvent {
    override fun toString(): String = "GroupDetailsChanged(memberCount=${details.members.size}, isArchived=$isArchived)"
@@ -166,11 +157,6 @@ sealed interface GroupSettingsEvent {
  /** The group's story became unviewed, viewed, or went away entirely. */
  data class StoryViewStateChanged(val storyViewState: StoryViewState) : GroupSettingsEvent

-  /** The shared media rail finished loading, either for the first time or after a refresh. */
-  data class SharedMediaChanged(val media: List<MediaTable.MediaRecord>) : GroupSettingsEvent {
-    override fun toString(): String = "SharedMediaChanged(count=${media.size})"
-  }
-
  /** The calls behind the call info variant of this screen finished loading. */
  data class CallsChanged(val calls: List<CallEntry>) : GroupSettingsEvent {
    override fun toString(): String = "CallsChanged(count=${calls.size})"
@@ -178,4 +164,15 @@ sealed interface GroupSettingsEvent {

  /** The group's thread id came back, or -1 if it doesn't have a thread yet. */
  data class ThreadIdLoaded(val threadId: Long) : GroupSettingsEvent
+
+  /** Received an event from the media rail that we want to forward */
+  data class MediaRailEvent(val event: RecentMediaRailEvents) : GroupSettingsEvent
+
+  /** The media rail's presenter emitted new state for us to mirror. */
+  data class MediaRailStateChanged(val railState: RecentMediaRailState) : GroupSettingsEvent {
+    override fun toString(): String = "MediaRailStateChanged(count=${railState.media.size}, loaded=${railState.loaded})"
+  }
+
+  /** The media rail's presenter decided something needs doing that only this screen can do. */
+  data class MediaRailAction(val action: RecentMediaRailAction) : GroupSettingsEvent
 }
@@ -78,7 +78,6 @@ fun GroupSettingsScreen(
  onEvent: (GroupSettingsEvent) -> Unit,
  onNavigationClick: () -> Unit,
  onAvatarViewCreated: (View) -> Unit,
-  onSharedMediaViewClicked: (View) -> Unit,
  modifier: Modifier = Modifier
 ) {
  ConversationSettingsScaffold(
@@ -198,11 +197,8 @@ fun GroupSettingsScreen(
    }

    sharedMediaSection(
-      media = state.sharedMedia,
-      loaded = state.sharedMediaLoaded,
-      onMediaClick = { mediaRecord, isLtr -> onEvent(GroupSettingsEvent.SharedMediaClicked(mediaRecord, isLtr)) },
-      onMediaViewClicked = onSharedMediaViewClicked,
-      onSeeAllClick = { onEvent(GroupSettingsEvent.SeeAllSharedMediaClicked) }
+      state = state.mediaRail,
+      onEvent = { onEvent(GroupSettingsEvent.MediaRailEvent(it)) }
    )

    membershipSection(state, onEvent)
@@ -668,7 +664,6 @@ private fun previewState(
    groupId = PREVIEW_GROUP_ID,
    recipient = recipient,
    threadId = 1L,
-    sharedMediaLoaded = true,
    canModifyBlockedState = true,
    allMembers = allMembers,
    membersExpanded = membersExpanded,
@@ -698,8 +693,7 @@ private fun GroupSettingsScreenPreview(state: GroupSettingsState) {
      state = state,
      onEvent = {},
      onNavigationClick = {},
-      onAvatarViewCreated = {},
-      onSharedMediaViewClicked = {}
+      onAvatarViewCreated = {}
    )
  }
 }
@@ -5,12 +5,12 @@

 package org.thoughtcrime.securesms.components.settings.conversation.group

+import org.signal.uicomponents.recentmediarail.RecentMediaRailState
 import org.thoughtcrime.securesms.components.settings.conversation.shared.CallBarState
 import org.thoughtcrime.securesms.components.settings.conversation.shared.CallEntry
 import org.thoughtcrime.securesms.components.settings.conversation.shared.CollapsibleList
 import org.thoughtcrime.securesms.components.settings.conversation.shared.GroupMember
 import org.thoughtcrime.securesms.components.settings.conversation.shared.LegacyGroupState
-import org.thoughtcrime.securesms.database.MediaTable
 import org.thoughtcrime.securesms.database.model.StoryViewState
 import org.thoughtcrime.securesms.groups.GroupId
 import org.thoughtcrime.securesms.groups.memberlabel.StyledMemberLabel
@@ -31,8 +31,7 @@ data class GroupSettingsState(
  val disappearingMessagesLifespan: Int = 0,
  val canModifyBlockedState: Boolean = false,
  val isArchived: Boolean = false,
-  val sharedMedia: List<MediaTable.MediaRecord> = emptyList(),
-  val sharedMediaLoaded: Boolean = false,
+  val mediaRail: RecentMediaRailState = RecentMediaRailState(),
  val calls: List<CallEntry> = emptyList(),
  val callBar: CallBarState = CallBarState(),
  val title: String = "",
@@ -21,6 +21,8 @@ import kotlinx.coroutines.flow.update
 import kotlinx.coroutines.launch
 import org.signal.core.ui.compose.EventDrivenViewModel
 import org.signal.core.util.logging.Log
+import org.signal.uicomponents.recentmediarail.RecentMediaRailEvents
+import org.signal.uicomponents.recentmediarail.RecentMediaRailPresenter
 import org.thoughtcrime.securesms.components.settings.conversation.ConversationSettingsAction
 import org.thoughtcrime.securesms.components.settings.conversation.ConversationSettingsRepository
 import org.thoughtcrime.securesms.components.settings.conversation.ConversationSettingsRepository.GroupDetails
@@ -28,7 +30,7 @@ import org.thoughtcrime.securesms.components.settings.conversation.group.GroupSe
 import org.thoughtcrime.securesms.components.settings.conversation.shared.BlockAndSpamHandler
 import org.thoughtcrime.securesms.components.settings.conversation.shared.CallBarState
 import org.thoughtcrime.securesms.components.settings.conversation.shared.SharedMediaLoader
-import org.thoughtcrime.securesms.components.settings.conversation.shared.sharedMediaClickAction
+import org.thoughtcrime.securesms.components.settings.conversation.shared.toConversationSettingsAction
 import org.thoughtcrime.securesms.groups.GroupId
 import org.thoughtcrime.securesms.groups.SelectionLimits
 import org.thoughtcrime.securesms.groups.v2.GroupAddMembersResult
@@ -66,6 +68,7 @@ class GroupSettingsViewModel(
  val actions: Flow<ConversationSettingsAction> = _actions.receiveAsFlow()

  private val sharedMediaLoader = SharedMediaLoader(repository)
+  private val mediaRailPresenter = RecentMediaRailPresenter(viewModelScope, sharedMediaLoader)

  init {
    repository
@@ -81,9 +84,14 @@ class GroupSettingsViewModel(
      .onEach { onEvent(GroupSettingsEvent.StoryViewStateChanged(it)) }
      .launchIn(viewModelScope)

-    sharedMediaLoader
-      .observe()
-      .onEach { onEvent(GroupSettingsEvent.SharedMediaChanged(it)) }
+    mediaRailPresenter
+      .state
+      .onEach { onEvent(GroupSettingsEvent.MediaRailStateChanged(it)) }
+      .launchIn(viewModelScope)
+
+    mediaRailPresenter
+      .actions
+      .onEach { onEvent(GroupSettingsEvent.MediaRailAction(it)) }
      .launchIn(viewModelScope)

    if (callMessageIds.isNotEmpty()) {
@@ -185,10 +193,6 @@ class GroupSettingsViewModel(

      GroupSettingsEvent.StarredMessagesClicked -> _actions.send(ConversationSettingsAction.OpenStarredMessages(state.threadId))

-      is GroupSettingsEvent.SharedMediaClicked -> _actions.send(sharedMediaClickAction(event.mediaRecord, event.isLtr))
-
-      GroupSettingsEvent.SeeAllSharedMediaClicked -> _actions.send(ConversationSettingsAction.ShowMediaOverview(state.threadId))
-
      GroupSettingsEvent.MemberSearchClicked -> {
        _actions.send(ConversationSettingsAction.NavigateToMemberSearch(groupId, state.canAddMembers, state.groupLinkEnabled))
      }
@@ -283,10 +287,6 @@ class GroupSettingsViewModel(
        _state.update { it.copy(dialog = Dialog.None) }
      }

-      GroupSettingsEvent.SharedMediaRefreshRequested -> {
-        sharedMediaLoader.refresh()
-      }
-
      is GroupSettingsEvent.GroupDetailsChanged -> {
        _state.update { it.applyGroupDetails(event.details, event.isArchived) }
      }
@@ -304,17 +304,25 @@ class GroupSettingsViewModel(
        _state.update { it.copy(storyViewState = event.storyViewState) }
      }

-      is GroupSettingsEvent.SharedMediaChanged -> {
-        _state.update { it.copy(sharedMedia = event.media, sharedMediaLoaded = true) }
-      }
-
      is GroupSettingsEvent.CallsChanged -> {
        _state.update { it.copy(calls = event.calls) }
      }

      is GroupSettingsEvent.ThreadIdLoaded -> {
        _state.update { it.copy(threadId = event.threadId) }
-        sharedMediaLoader.onThreadIdLoaded(event.threadId)
+        mediaRailPresenter.onEvent(RecentMediaRailEvents.SourceChanged(event.threadId))
+      }
+
+      is GroupSettingsEvent.MediaRailEvent -> {
+        mediaRailPresenter.onEvent(event.event)
+      }
+
+      is GroupSettingsEvent.MediaRailStateChanged -> {
+        _state.update { it.copy(mediaRail = event.railState) }
+      }
+
+      is GroupSettingsEvent.MediaRailAction -> {
+        event.action.toConversationSettingsAction(sharedMediaLoader, state.threadId)?.let { _actions.send(it) }
      }
    }
  }
@@ -5,9 +5,11 @@

 package org.thoughtcrime.securesms.components.settings.conversation.individual

+import org.signal.uicomponents.recentmediarail.RecentMediaRailAction
+import org.signal.uicomponents.recentmediarail.RecentMediaRailEvents
+import org.signal.uicomponents.recentmediarail.RecentMediaRailState
 import org.thoughtcrime.securesms.badges.models.Badge
 import org.thoughtcrime.securesms.components.settings.conversation.shared.CallEntry
-import org.thoughtcrime.securesms.database.MediaTable
 import org.thoughtcrime.securesms.database.model.IdentityRecord
 import org.thoughtcrime.securesms.database.model.StoryViewState
 import org.thoughtcrime.securesms.recipients.Recipient
@@ -80,14 +82,6 @@ sealed interface IndividualSettingsEvent {
  /** The user tapped the safety number row. */
  data object ViewSafetyNumberClicked : IndividualSettingsEvent

-  /** The user tapped an item in the shared media rail, carrying the media that item stands for. */
-  data class SharedMediaClicked(val mediaRecord: MediaTable.MediaRecord, val isLtr: Boolean) : IndividualSettingsEvent {
-    override fun toString(): String = "SharedMediaClicked(messageId=${mediaRecord.messageId}, isLtr=$isLtr)"
-  }
-
-  /** The user tapped "see all" on the shared media rail, which opens the media overview. */
-  data object SeeAllSharedMediaClicked : IndividualSettingsEvent
-
  /** The user tapped the support center link, which only the release notes chat offers. */
  data object SupportCenterClicked : IndividualSettingsEvent

@@ -127,9 +121,6 @@ sealed interface IndividualSettingsEvent {
  /** Dismisses whatever is in [IndividualSettingsState.dialog]. */
  data object DialogDismissed : IndividualSettingsEvent

-  /** The user came back from the media viewer, so the shared media rail may be out of date. */
-  data object SharedMediaRefreshRequested : IndividualSettingsEvent
-
  /** The user came back from adding or viewing a system contact, so the recipient may be out of date. */
  data object RecipientRefreshRequested : IndividualSettingsEvent

@@ -141,11 +132,6 @@ sealed interface IndividualSettingsEvent {
  /** The recipient's story became unviewed, viewed, or went away entirely. */
  data class StoryViewStateChanged(val storyViewState: StoryViewState) : IndividualSettingsEvent

-  /** The shared media rail finished loading, either for the first time or after a refresh. */
-  data class SharedMediaChanged(val media: List<MediaTable.MediaRecord>) : IndividualSettingsEvent {
-    override fun toString(): String = "SharedMediaChanged(count=${media.size})"
-  }
-
  /** The calls behind the call info variant of this screen finished loading. */
  data class CallsChanged(val calls: List<CallEntry>) : IndividualSettingsEvent {
    override fun toString(): String = "CallsChanged(count=${calls.size})"
@@ -166,4 +152,15 @@ sealed interface IndividualSettingsEvent {
  data class IdentityRecordLoaded(val identityRecord: IdentityRecord?) : IndividualSettingsEvent {
    override fun toString(): String = "IdentityRecordLoaded(present=${identityRecord != null})"
  }
+
+  /** Received an event from the media rail that we want to forward */
+  data class MediaRailEvent(val event: RecentMediaRailEvents) : IndividualSettingsEvent
+
+  /** The media rail's presenter emitted new state for us to mirror. */
+  data class MediaRailStateChanged(val railState: RecentMediaRailState) : IndividualSettingsEvent {
+    override fun toString(): String = "MediaRailStateChanged(count=${railState.media.size}, loaded=${railState.loaded})"
+  }
+
+  /** The media rail's presenter decided something needs doing that only this screen can do. */
+  data class MediaRailAction(val action: RecentMediaRailAction) : IndividualSettingsEvent
 }
@@ -65,7 +65,6 @@ fun IndividualSettingsScreen(
  onEvent: (IndividualSettingsEvent) -> Unit,
  onNavigationClick: () -> Unit,
  onAvatarViewCreated: (View) -> Unit,
-  onSharedMediaViewClicked: (View) -> Unit,
  modifier: Modifier = Modifier
 ) {
  val context = LocalContext.current
@@ -189,11 +188,8 @@ fun IndividualSettingsScreen(
    }

    sharedMediaSection(
-      media = state.sharedMedia,
-      loaded = state.sharedMediaLoaded,
-      onMediaClick = { mediaRecord, isLtr -> onEvent(IndividualSettingsEvent.SharedMediaClicked(mediaRecord, isLtr)) },
-      onMediaViewClicked = onSharedMediaViewClicked,
-      onSeeAllClick = { onEvent(IndividualSettingsEvent.SeeAllSharedMediaClicked) }
+      state = state.mediaRail,
+      onEvent = { onEvent(IndividualSettingsEvent.MediaRailEvent(it)) }
    )

    badgeSection(state, onEvent)
@@ -360,7 +356,6 @@ private fun IndividualSettingsScreenPreview() {
      state = IndividualSettingsState(
        recipient = previewRecipient(1L, profileName = ProfileName.fromParts("Miles", "Morales"), about = "Just hanging around"),
        threadId = 1L,
-        sharedMediaLoaded = true,
        canModifyBlockedState = true,
        starredMessagesEnabled = true,
        selfHasGroups = true,
@@ -375,8 +370,7 @@ private fun IndividualSettingsScreenPreview() {
      ),
      onEvent = {},
      onNavigationClick = {},
-      onAvatarViewCreated = {},
-      onSharedMediaViewClicked = {}
+      onAvatarViewCreated = {}
    )
  }
 }
@@ -5,10 +5,10 @@

 package org.thoughtcrime.securesms.components.settings.conversation.individual

+import org.signal.uicomponents.recentmediarail.RecentMediaRailState
 import org.thoughtcrime.securesms.components.settings.conversation.shared.CallBarState
 import org.thoughtcrime.securesms.components.settings.conversation.shared.CallEntry
 import org.thoughtcrime.securesms.components.settings.conversation.shared.CollapsibleList
-import org.thoughtcrime.securesms.database.MediaTable
 import org.thoughtcrime.securesms.database.model.IdentityRecord
 import org.thoughtcrime.securesms.database.model.StoryViewState
 import org.thoughtcrime.securesms.recipients.Recipient
@@ -30,8 +30,7 @@ data class IndividualSettingsState(
  val allGroupsInCommon: List<Recipient> = emptyList(),
  val selfHasGroups: Boolean = false,
  val groupsInCommonExpanded: Boolean = false,
-  val sharedMedia: List<MediaTable.MediaRecord> = emptyList(),
-  val sharedMediaLoaded: Boolean = false,
+  val mediaRail: RecentMediaRailState = RecentMediaRailState(),
  val calls: List<CallEntry> = emptyList(),
  val callBar: CallBarState = CallBarState(),
  val dialog: Dialog = Dialog.None
@@ -21,6 +21,8 @@ import kotlinx.coroutines.flow.update
 import kotlinx.coroutines.launch
 import org.signal.core.ui.compose.EventDrivenViewModel
 import org.signal.core.util.logging.Log
+import org.signal.uicomponents.recentmediarail.RecentMediaRailEvents
+import org.signal.uicomponents.recentmediarail.RecentMediaRailPresenter
 import org.thoughtcrime.securesms.components.settings.conversation.ConversationSettingsAction
 import org.thoughtcrime.securesms.components.settings.conversation.ConversationSettingsKind
 import org.thoughtcrime.securesms.components.settings.conversation.ConversationSettingsRepository
@@ -28,7 +30,7 @@ import org.thoughtcrime.securesms.components.settings.conversation.individual.In
 import org.thoughtcrime.securesms.components.settings.conversation.shared.BlockAndSpamHandler
 import org.thoughtcrime.securesms.components.settings.conversation.shared.CallBarState
 import org.thoughtcrime.securesms.components.settings.conversation.shared.SharedMediaLoader
-import org.thoughtcrime.securesms.components.settings.conversation.shared.sharedMediaClickAction
+import org.thoughtcrime.securesms.components.settings.conversation.shared.toConversationSettingsAction
 import org.thoughtcrime.securesms.recipients.Recipient
 import org.thoughtcrime.securesms.recipients.RecipientId

@@ -50,6 +52,9 @@ class IndividualSettingsViewModel(
  /** Whether we're the call-info variant of this screen, which shows a message button in place of search. */
  private val isCallInfoVariant: Boolean = callMessageIds.isNotEmpty()

+  /** The release notes chat doesn't show a media rail, so there's no reason to go load one. */
+  private val showsSharedMedia: Boolean = kind != ConversationSettingsKind.RELEASE_NOTES
+
  private val _state = MutableStateFlow(
    IndividualSettingsState(
      isDeprecatedOrUnregistered = repository.isDeprecatedOrUnregistered(),
@@ -65,6 +70,7 @@ class IndividualSettingsViewModel(
  val actions: Flow<ConversationSettingsAction> = _actions.receiveAsFlow()

  private val sharedMediaLoader = SharedMediaLoader(repository)
+  private val mediaRailPresenter = RecentMediaRailPresenter(viewModelScope, sharedMediaLoader)

  init {
    require(kind != ConversationSettingsKind.GROUP) { "Groups belong to GroupSettingsViewModel" }
@@ -79,9 +85,14 @@ class IndividualSettingsViewModel(
      .onEach { onEvent(IndividualSettingsEvent.StoryViewStateChanged(it)) }
      .launchIn(viewModelScope)

-    sharedMediaLoader
-      .observe()
-      .onEach { onEvent(IndividualSettingsEvent.SharedMediaChanged(it)) }
+    mediaRailPresenter
+      .state
+      .onEach { onEvent(IndividualSettingsEvent.MediaRailStateChanged(it)) }
+      .launchIn(viewModelScope)
+
+    mediaRailPresenter
+      .actions
+      .onEach { onEvent(IndividualSettingsEvent.MediaRailAction(it)) }
      .launchIn(viewModelScope)

    if (callMessageIds.isNotEmpty()) {
@@ -181,12 +192,6 @@ class IndividualSettingsViewModel(
        _state.update { it.copy(identityRecord = identityRecord) }
        _actions.send(ConversationSettingsAction.ShowSafetyNumber(identityRecord))
      }
-      is IndividualSettingsEvent.SharedMediaClicked -> {
-        _actions.send(sharedMediaClickAction(event.mediaRecord, event.isLtr))
-      }
-      IndividualSettingsEvent.SeeAllSharedMediaClicked -> {
-        _actions.send(ConversationSettingsAction.ShowMediaOverview(state.threadId))
-      }
      IndividualSettingsEvent.SupportCenterClicked -> {
        _actions.send(ConversationSettingsAction.OpenSupportCenter)
      }
@@ -233,9 +238,6 @@ class IndividualSettingsViewModel(
      IndividualSettingsEvent.DialogDismissed -> {
        _state.update { it.copy(dialog = Dialog.None) }
      }
-      IndividualSettingsEvent.SharedMediaRefreshRequested -> {
-        sharedMediaLoader.refresh()
-      }
      IndividualSettingsEvent.RecipientRefreshRequested -> {
        repository.refreshRecipient(recipientId)
      }
@@ -245,15 +247,14 @@ class IndividualSettingsViewModel(
      is IndividualSettingsEvent.StoryViewStateChanged -> {
        _state.update { it.copy(storyViewState = event.storyViewState) }
      }
-      is IndividualSettingsEvent.SharedMediaChanged -> {
-        _state.update { it.copy(sharedMedia = event.media, sharedMediaLoaded = true) }
-      }
      is IndividualSettingsEvent.CallsChanged -> {
        _state.update { it.copy(calls = event.calls) }
      }
      is IndividualSettingsEvent.ThreadIdLoaded -> {
        _state.update { it.copy(threadId = event.threadId) }
-        sharedMediaLoader.onThreadIdLoaded(event.threadId)
+        if (showsSharedMedia) {
+          mediaRailPresenter.onEvent(RecentMediaRailEvents.SourceChanged(event.threadId))
+        }
      }
      is IndividualSettingsEvent.GroupsInCommonChanged -> {
        _state.update { it.copy(allGroupsInCommon = event.groupsInCommon) }
@@ -264,6 +265,15 @@ class IndividualSettingsViewModel(
      is IndividualSettingsEvent.IdentityRecordLoaded -> {
        _state.update { it.copy(identityRecord = event.identityRecord) }
      }
+      is IndividualSettingsEvent.MediaRailEvent -> {
+        mediaRailPresenter.onEvent(event.event)
+      }
+      is IndividualSettingsEvent.MediaRailStateChanged -> {
+        _state.update { it.copy(mediaRail = event.railState) }
+      }
+      is IndividualSettingsEvent.MediaRailAction -> {
+        event.action.toConversationSettingsAction(sharedMediaLoader, state.threadId)?.let { _actions.send(it) }
+      }
    }
  }

@@ -34,7 +34,6 @@ fun NoteToSelfSettingsScreen(
  onEvent: (IndividualSettingsEvent) -> Unit,
  onNavigationClick: () -> Unit,
  onAvatarViewCreated: (View) -> Unit,
-  onSharedMediaViewClicked: (View) -> Unit,
  modifier: Modifier = Modifier
 ) {
  ConversationSettingsScaffold(
@@ -101,11 +100,8 @@ fun NoteToSelfSettingsScreen(
    }

    sharedMediaSection(
-      media = state.sharedMedia,
-      loaded = state.sharedMediaLoaded,
-      onMediaClick = { mediaRecord, isLtr -> onEvent(IndividualSettingsEvent.SharedMediaClicked(mediaRecord, isLtr)) },
-      onMediaViewClicked = onSharedMediaViewClicked,
-      onSeeAllClick = { onEvent(IndividualSettingsEvent.SeeAllSharedMediaClicked) }
+      state = state.mediaRail,
+      onEvent = { onEvent(IndividualSettingsEvent.MediaRailEvent(it)) }
    )
  }
 }
@@ -118,14 +114,12 @@ private fun NoteToSelfSettingsScreenPreview() {
      state = IndividualSettingsState(
        recipient = previewRecipient(1L, isSelf = true),
        threadId = 1L,
-        sharedMediaLoaded = true,
        starredMessagesEnabled = true,
        callBar = CallBarState(isSearchAvailable = true)
      ),
      onEvent = {},
      onNavigationClick = {},
-      onAvatarViewCreated = {},
-      onSharedMediaViewClicked = {}
+      onAvatarViewCreated = {}
    )
  }
 }
@@ -27,7 +27,6 @@ import org.thoughtcrime.securesms.components.settings.conversation.shared.Intern
 import org.thoughtcrime.securesms.components.settings.conversation.shared.SoundsAndNotificationsRow
 import org.thoughtcrime.securesms.components.settings.conversation.shared.UnmuteDialog
 import org.thoughtcrime.securesms.components.settings.conversation.shared.previewRecipient
-import org.thoughtcrime.securesms.components.settings.conversation.shared.sharedMediaSection
 import org.thoughtcrime.securesms.profiles.ProfileName
 import org.thoughtcrime.securesms.recipients.Recipient

@@ -40,7 +39,6 @@ fun ReleaseNotesSettingsScreen(
  onEvent: (IndividualSettingsEvent) -> Unit,
  onNavigationClick: () -> Unit,
  onAvatarViewCreated: (View) -> Unit,
-  onSharedMediaViewClicked: (View) -> Unit,
  modifier: Modifier = Modifier
 ) {
  val context = LocalContext.current
@@ -114,14 +112,6 @@ fun ReleaseNotesSettingsScreen(
      )
    }

-    sharedMediaSection(
-      media = state.sharedMedia,
-      loaded = state.sharedMediaLoaded,
-      onMediaClick = { mediaRecord, isLtr -> onEvent(IndividualSettingsEvent.SharedMediaClicked(mediaRecord, isLtr)) },
-      onMediaViewClicked = onSharedMediaViewClicked,
-      onSeeAllClick = { onEvent(IndividualSettingsEvent.SeeAllSharedMediaClicked) }
-    )
-
    item { Dividers.Default() }

    item { Texts.SectionHeader(text = stringResource(R.string.preferences__help)) }
@@ -194,14 +184,12 @@ private fun ReleaseNotesSettingsScreenPreview() {
      state = IndividualSettingsState(
        recipient = previewRecipient(1L, profileName = ProfileName.fromParts("Signal", null), isReleaseNotes = true),
        threadId = 1L,
-        sharedMediaLoaded = true,
        canModifyBlockedState = true,
        callBar = CallBarState(isMuteAvailable = true, isSearchAvailable = true)
      ),
      onEvent = {},
      onNavigationClick = {},
-      onAvatarViewCreated = {},
-      onSharedMediaViewClicked = {}
+      onAvatarViewCreated = {}
    )
  }
 }
@@ -0,0 +1,30 @@
+/*
+ * Copyright 2026 Signal Messenger, LLC
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+package org.thoughtcrime.securesms.components.settings.conversation.shared
+
+import org.signal.uicomponents.recentmediarail.RecentMediaRailAction
+import org.thoughtcrime.securesms.components.settings.conversation.ConversationSettingsAction
+
+/**
+ * Translates something the shared media rail decided needs doing into the settings action that carries it out, or null
+ * if the media it refers to has since gone away.
+ */
+fun RecentMediaRailAction.toConversationSettingsAction(loader: SharedMediaLoader, threadId: Long): ConversationSettingsAction? {
+  return when (this) {
+    is RecentMediaRailAction.OpenMedia -> {
+      loader.recordAt(index)?.let { ConversationSettingsAction.ShowMediaPreview(it, leftToRight, bounds) }
+    }
+    is RecentMediaRailAction.DownloadMedia -> {
+      loader.recordAt(index)?.let { ConversationSettingsAction.DownloadMedia(it) }
+    }
+    RecentMediaRailAction.ShowMediaUnavailable -> {
+      ConversationSettingsAction.ShowMediaNotSentYet
+    }
+    RecentMediaRailAction.OpenAllMedia -> {
+      ConversationSettingsAction.ShowMediaOverview(threadId)
+    }
+  }
+}
@@ -1,35 +0,0 @@
-/*
- * Copyright 2026 Signal Messenger, LLC
- * SPDX-License-Identifier: AGPL-3.0-only
- */
-
-package org.thoughtcrime.securesms.components.settings.conversation.shared
-
-import org.thoughtcrime.securesms.components.settings.conversation.ConversationSettingsAction
-import org.thoughtcrime.securesms.database.AttachmentTable
-import org.thoughtcrime.securesms.database.MediaTable
-
-/** Where a tap on the shared media rail should go, which depends on whether the attachment is actually here yet. */
-fun sharedMediaClickAction(mediaRecord: MediaTable.MediaRecord, isLtr: Boolean): ConversationSettingsAction {
-  val attachment = mediaRecord.attachment
-
-  return when {
-    attachment == null -> {
-      ConversationSettingsAction.ShowMediaNotSentYet
-    }
-    attachment.displayUri == null -> {
-      if (attachment.transferState == AttachmentTable.TRANSFER_RESTORE_OFFLOADED) {
-        ConversationSettingsAction.DownloadMedia(mediaRecord)
-      } else {
-        ConversationSettingsAction.ShowMediaNotSentYet
-      }
-    }
-    attachment.transferState != AttachmentTable.TRANSFER_PROGRESS_DONE &&
-      attachment.transferState != AttachmentTable.TRANSFER_RESTORE_OFFLOADED -> {
-      ConversationSettingsAction.ShowMediaNotSentYet
-    }
-    else -> {
-      ConversationSettingsAction.ShowMediaPreview(mediaRecord, isLtr)
-    }
-  }
-}
@@ -5,40 +5,65 @@

 package org.thoughtcrime.securesms.components.settings.conversation.shared

-import kotlinx.coroutines.flow.Flow
-import kotlinx.coroutines.flow.MutableSharedFlow
-import kotlinx.coroutines.flow.MutableStateFlow
-import kotlinx.coroutines.flow.combine
-import kotlinx.coroutines.flow.distinctUntilChanged
-import kotlinx.coroutines.flow.filterNotNull
-import kotlinx.coroutines.flow.map
+import org.signal.uicomponents.recentmediarail.RecentMedia
+import org.signal.uicomponents.recentmediarail.RecentMedia.Availability
+import org.signal.uicomponents.recentmediarail.RecentMediaRailPresenter
 import org.thoughtcrime.securesms.components.settings.conversation.ConversationSettingsRepository
+import org.thoughtcrime.securesms.database.AttachmentTable
 import org.thoughtcrime.securesms.database.MediaTable

 private const val SHARED_MEDIA_LIMIT = 100

 /**
- * Loads the shared media rail for a thread, and lets the host ask for a reload after the user comes back from the
- * media viewer. Held by each conversation settings view model, which applies the results to its own state.
+ * Feeds the shared media rail for a thread. Held by each conversation settings view model, which hands it to the rail's
+ * presenter.
 *
- * Nothing is emitted until the thread id has been resolved, so that a screen can tell "still loading" apart from
- * "this chat has no media" and reserve space for the rail accordingly.
+ * The rail itself only ever refers to media by position, so this also hangs onto the records it last loaded so that the
+ * view model can turn a tap back into the media it stands for.
 */
-class SharedMediaLoader(private val repository: ConversationSettingsRepository) {
+class SharedMediaLoader(private val repository: ConversationSettingsRepository) : RecentMediaRailPresenter.Loader {

-  private val refreshTrigger = MutableSharedFlow<Unit>(replay = 1).apply { tryEmit(Unit) }
-  private val threadId = MutableStateFlow<Long?>(null)
+  @Volatile
+  private var records: List<MediaTable.MediaRecord> = emptyList()

-  fun onThreadIdLoaded(threadId: Long) {
-    this.threadId.value = threadId
+  override suspend fun load(sourceId: Long): List<RecentMedia> {
+    val loaded = repository.getSharedMedia(sourceId, SHARED_MEDIA_LIMIT)
+    records = loaded
+    return loaded.map { it.toRecentMedia() }
  }

-  fun refresh() {
-    refreshTrigger.tryEmit(Unit)
-  }
+  fun recordAt(index: Int): MediaTable.MediaRecord? = records.getOrNull(index)
+}

-  fun observe(): Flow<List<MediaTable.MediaRecord>> {
-    return combine(threadId.filterNotNull().distinctUntilChanged(), refreshTrigger) { id, _ -> id }
-      .map { repository.getSharedMedia(it, SHARED_MEDIA_LIMIT) }
+private fun MediaTable.MediaRecord.toRecentMedia(): RecentMedia {
+  return RecentMedia(
+    thumbnailUri = attachment?.displayUri,
+    availability = availability(),
+    thumbnailTimeUs = attachment?.transformProperties?.videoTrimStartTimeUs ?: 0
+  )
+}
+
+/** Whether the attachment behind this record is actually here yet, and if not, whether we can go get it. */
+private fun MediaTable.MediaRecord.availability(): Availability {
+  val attachment = this.attachment
+
+  return when {
+    attachment == null -> {
+      Availability.UNAVAILABLE
+    }
+    attachment.displayUri == null -> {
+      if (attachment.transferState == AttachmentTable.TRANSFER_RESTORE_OFFLOADED) {
+        Availability.RESTORABLE
+      } else {
+        Availability.UNAVAILABLE
+      }
+    }
+    attachment.transferState != AttachmentTable.TRANSFER_PROGRESS_DONE &&
+      attachment.transferState != AttachmentTable.TRANSFER_RESTORE_OFFLOADED -> {
+      Availability.UNAVAILABLE
+    }
+    else -> {
+      Availability.AVAILABLE
+    }
  }
 }
@@ -5,42 +5,27 @@

 package org.thoughtcrime.securesms.components.settings.conversation.shared

-import android.view.View
-import androidx.compose.foundation.layout.fillMaxWidth
-import androidx.compose.foundation.layout.height
 import androidx.compose.foundation.lazy.LazyListScope
-import androidx.compose.runtime.Composable
-import androidx.compose.ui.Modifier
-import androidx.compose.ui.platform.LocalLayoutDirection
 import androidx.compose.ui.res.stringResource
-import androidx.compose.ui.unit.LayoutDirection
-import androidx.compose.ui.unit.dp
-import androidx.compose.ui.viewinterop.AndroidView
-import com.bumptech.glide.Glide
 import org.signal.core.ui.compose.Dividers
 import org.signal.core.ui.compose.Rows
 import org.signal.core.ui.compose.Texts
+import org.signal.uicomponents.recentmediarail.RecentMediaRail
+import org.signal.uicomponents.recentmediarail.RecentMediaRailEvents
+import org.signal.uicomponents.recentmediarail.RecentMediaRailState
 import org.thoughtcrime.securesms.R
-import org.thoughtcrime.securesms.components.ThreadPhotoRailView
-import org.thoughtcrime.securesms.database.MediaTable
-
-private val RAIL_HEIGHT = 80.dp

 /**
 * The shared media rail and its "see all" row, which every conversation type shows.
 *
- * The rail is a fixed height and stays in the layout while [loaded] is false, so that media arriving later fills in
- * space that was already there instead of shoving the rest of the screen down. It's only dropped once we know the chat
- * has no media at all.
+ * Dropped entirely once we know the chat has no media at all -- until then the rail keeps its space, so media arriving
+ * later doesn't shove the rest of the screen down.
 */
 fun LazyListScope.sharedMediaSection(
-  media: List<MediaTable.MediaRecord>,
-  loaded: Boolean,
-  onMediaClick: (MediaTable.MediaRecord, Boolean) -> Unit,
-  onMediaViewClicked: (View) -> Unit,
-  onSeeAllClick: () -> Unit
+  state: RecentMediaRailState,
+  onEvent: (RecentMediaRailEvents) -> Unit
 ) {
-  if (loaded && media.isEmpty()) {
+  if (!state.visible) {
    return
  }

@@ -49,40 +34,16 @@ fun LazyListScope.sharedMediaSection(
  item { Texts.SectionHeader(text = stringResource(R.string.recipient_preference_activity__shared_media)) }

  item {
-    SharedMediaRail(
-      media = media,
-      onMediaClick = onMediaClick,
-      onMediaViewClicked = onMediaViewClicked
+    RecentMediaRail(
+      state = state,
+      onEvent = onEvent
    )
  }

  item {
    Rows.TextRow(
      text = stringResource(R.string.ConversationSettingsFragment__see_all),
-      onClick = onSeeAllClick
+      onClick = { onEvent(RecentMediaRailEvents.SeeAllClicked) }
    )
  }
 }
-
-@Composable
-private fun SharedMediaRail(
-  media: List<MediaTable.MediaRecord>,
-  onMediaClick: (MediaTable.MediaRecord, Boolean) -> Unit,
-  onMediaViewClicked: (View) -> Unit,
-  modifier: Modifier = Modifier
-) {
-  val isLtr = LocalLayoutDirection.current == LayoutDirection.Ltr
-
-  AndroidView(
-    factory = { context -> ThreadPhotoRailView(context) },
-    modifier = modifier
-      .fillMaxWidth()
-      .height(RAIL_HEIGHT)
-  ) { railView ->
-    railView.setListener { view, mediaRecord ->
-      onMediaViewClicked(view)
-      onMediaClick(mediaRecord, isLtr)
-    }
-    railView.setMediaRecords(Glide.with(railView), media)
-  }
-}
@@ -1,18 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<merge xmlns:android="http://schemas.android.com/apk/res/android"
-    xmlns:tools="http://schemas.android.com/tools"
-    tools:viewBindingIgnore="true">
-
-    <androidx.recyclerview.widget.RecyclerView
-        android:id="@+id/photo_list"
-        android:layout_width="match_parent"
-        android:layout_height="match_parent"
-        android:clipToPadding="false"
-        android:nestedScrollingEnabled="false"
-        android:paddingStart="@dimen/dsl_settings_gutter"
-        android:paddingEnd="@dimen/dsl_settings_gutter"
-        android:scrollbars="none"
-        tools:layoutManager="androidx.recyclerview.widget.LinearLayoutManager"
-        tools:listitem="@layout/recipient_preference_photo_rail_item"
-        tools:orientation="horizontal" />
-</merge>
@@ -1,19 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<org.thoughtcrime.securesms.components.SquareFrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
-    xmlns:tools="http://schemas.android.com/tools"
-    tools:viewBindingIgnore="true"
-    xmlns:app="http://schemas.android.com/apk/res-auto"
-    android:layout_width="match_parent"
-    android:layout_height="match_parent"
-    android:layout_marginEnd="8dp"
-    app:square_height="true">
-
-    <org.thoughtcrime.securesms.components.ThumbnailView
-        android:id="@+id/thumbnail"
-        android:layout_width="match_parent"
-        android:layout_height="match_parent"
-        android:scaleType="centerCrop"
-        app:thumbnail_radius="12dp"
-        app:transparent_overlay_color="@color/transparent_black_08" />
-
-</org.thoughtcrime.securesms.components.SquareFrameLayout>
@@ -5,6 +5,7 @@

 package org.thoughtcrime.securesms.components.settings.conversation.group

+import androidx.compose.ui.unit.IntRect
 import io.mockk.coEvery
 import io.mockk.coVerify
 import io.mockk.every
@@ -28,6 +29,7 @@ import org.junit.Before
 import org.junit.Rule
 import org.junit.Test
 import org.signal.libsignal.zkgroup.groups.GroupMasterKey
+import org.signal.uicomponents.recentmediarail.RecentMediaRailEvents
 import org.thoughtcrime.securesms.components.settings.conversation.ConversationSettingsAction
 import org.thoughtcrime.securesms.components.settings.conversation.ConversationSettingsRepository
 import org.thoughtcrime.securesms.components.settings.conversation.ConversationSettingsRepository.GroupDetails
@@ -601,17 +603,18 @@ class GroupSettingsViewModelTest {
    val viewModel = createViewModel()
    val actions = collectActions(viewModel)

-    viewModel.onEvent(GroupSettingsEvent.SeeAllSharedMediaClicked)
+    viewModel.onEvent(GroupSettingsEvent.MediaRailEvent(RecentMediaRailEvents.SeeAllClicked))

    assertEquals(ConversationSettingsAction.ShowMediaOverview(THREAD_ID), actions.single())
  }

  @Test
  fun `shared media click reports the media is not sent yet when there is no attachment`() = runTest(testDispatcher) {
+    coEvery { repository.getSharedMedia(any(), any()) } returns listOf(mediaRecord())
    val viewModel = createViewModel()
    val actions = collectActions(viewModel)

-    viewModel.onEvent(GroupSettingsEvent.SharedMediaClicked(mediaRecord(), isLtr = true))
+    viewModel.onEvent(GroupSettingsEvent.MediaRailEvent(RecentMediaRailEvents.ItemClicked(index = 0, bounds = IntRect.Zero, leftToRight = true)))

    assertEquals(ConversationSettingsAction.ShowMediaNotSentYet, actions.single())
  }
@@ -5,6 +5,7 @@

 package org.thoughtcrime.securesms.components.settings.conversation.individual

+import androidx.compose.ui.unit.IntRect
 import io.mockk.coEvery
 import io.mockk.coVerify
 import io.mockk.every
@@ -30,6 +31,7 @@ import org.junit.Before
 import org.junit.Rule
 import org.junit.Test
 import org.signal.core.models.database.AttachmentId
+import org.signal.uicomponents.recentmediarail.RecentMediaRailEvents
 import org.thoughtcrime.securesms.attachments.Attachment
 import org.thoughtcrime.securesms.attachments.Cdn
 import org.thoughtcrime.securesms.attachments.DatabaseAttachment
@@ -89,8 +91,11 @@ class IndividualSettingsViewModelTest {

  private fun createViewModel(
    callMessageIds: LongArray = longArrayOf(),
-    kind: ConversationSettingsKind = ConversationSettingsKind.INDIVIDUAL
+    kind: ConversationSettingsKind = ConversationSettingsKind.INDIVIDUAL,
+    sharedMedia: List<MediaTable.MediaRecord> = emptyList()
  ): IndividualSettingsViewModel {
+    coEvery { repository.getSharedMedia(any(), any()) } returns sharedMedia
+
    return IndividualSettingsViewModel(
      recipientId = RECIPIENT_ID,
      kind = kind,
@@ -178,7 +183,7 @@ class IndividualSettingsViewModelTest {
    val viewModel = createViewModel()

    assertEquals(THREAD_ID, viewModel.state.value.threadId)
-    assertTrue(viewModel.state.value.sharedMediaLoaded)
+    assertTrue(viewModel.state.value.mediaRail.loaded)
    assertTrue(viewModel.state.value.isLoaded)
  }

@@ -379,7 +384,7 @@ class IndividualSettingsViewModelTest {
    val viewModel = createViewModel()
    val actions = collectActions(viewModel)

-    viewModel.onEvent(IndividualSettingsEvent.SeeAllSharedMediaClicked)
+    viewModel.onEvent(IndividualSettingsEvent.MediaRailEvent(RecentMediaRailEvents.SeeAllClicked))

    assertEquals(ConversationSettingsAction.ShowMediaOverview(THREAD_ID), actions.single())
  }
@@ -387,32 +392,31 @@ class IndividualSettingsViewModelTest {
  @Test
  fun `shared media click shows the preview for a downloaded attachment`() = runTest(testDispatcher) {
    val record = mediaRecord(attachment(transferState = AttachmentTable.TRANSFER_PROGRESS_DONE, hasUri = true))
-    val viewModel = createViewModel()
+    val viewModel = createViewModel(sharedMedia = listOf(record))
    val actions = collectActions(viewModel)

-    viewModel.onEvent(IndividualSettingsEvent.SharedMediaClicked(record, isLtr = true))
+    viewModel.onEvent(railItemClicked())

-    assertEquals(ConversationSettingsAction.ShowMediaPreview(record, true), actions.single())
+    assertEquals(ConversationSettingsAction.ShowMediaPreview(record, true, RAIL_ITEM_BOUNDS), actions.single())
  }

  @Test
  fun `shared media click downloads offloaded media that has no local file`() = runTest(testDispatcher) {
    val record = mediaRecord(attachment(transferState = AttachmentTable.TRANSFER_RESTORE_OFFLOADED, hasUri = false))
-    val viewModel = createViewModel()
+    val viewModel = createViewModel(sharedMedia = listOf(record))
    val actions = collectActions(viewModel)

-    viewModel.onEvent(IndividualSettingsEvent.SharedMediaClicked(record, isLtr = true))
+    viewModel.onEvent(railItemClicked())

    assertEquals(ConversationSettingsAction.DownloadMedia(record), actions.single())
  }

  @Test
  fun `shared media click reports the media is not sent yet when there is no attachment`() = runTest(testDispatcher) {
-    val record = mediaRecord(null)
-    val viewModel = createViewModel()
+    val viewModel = createViewModel(sharedMedia = listOf(mediaRecord(null)))
    val actions = collectActions(viewModel)

-    viewModel.onEvent(IndividualSettingsEvent.SharedMediaClicked(record, isLtr = true))
+    viewModel.onEvent(railItemClicked())

    assertEquals(ConversationSettingsAction.ShowMediaNotSentYet, actions.single())
  }
@@ -420,12 +424,22 @@ class IndividualSettingsViewModelTest {
  @Test
  fun `shared media click reports the media is not sent yet when it is still in flight`() = runTest(testDispatcher) {
    val record = mediaRecord(attachment(transferState = AttachmentTable.TRANSFER_PROGRESS_STARTED, hasUri = true))
+    val viewModel = createViewModel(sharedMedia = listOf(record))
+    val actions = collectActions(viewModel)
+
+    viewModel.onEvent(railItemClicked())
+
+    assertEquals(ConversationSettingsAction.ShowMediaNotSentYet, actions.single())
+  }
+
+  @Test
+  fun `shared media click is ignored when the rail no longer has that item`() = runTest(testDispatcher) {
    val viewModel = createViewModel()
    val actions = collectActions(viewModel)

-    viewModel.onEvent(IndividualSettingsEvent.SharedMediaClicked(record, isLtr = true))
+    viewModel.onEvent(railItemClicked())

-    assertEquals(ConversationSettingsAction.ShowMediaNotSentYet, actions.single())
+    assertTrue(actions.isEmpty())
  }

  @Test
@@ -739,6 +753,7 @@ class IndividualSettingsViewModelTest {
  private companion object {
    val RECIPIENT_ID: RecipientId = RecipientId.from(1L)
    const val THREAD_ID = 5L
+    val RAIL_ITEM_BOUNDS = IntRect(left = 16, top = 100, right = 96, bottom = 180)

    fun individual(
      isBlocked: Boolean = false,
@@ -775,6 +790,11 @@ class IndividualSettingsViewModelTest {
      }
    }

+    /** The first rail item being tapped, which is all these tests ever need. */
+    fun railItemClicked(): IndividualSettingsEvent.MediaRailEvent {
+      return IndividualSettingsEvent.MediaRailEvent(RecentMediaRailEvents.ItemClicked(index = 0, bounds = RAIL_ITEM_BOUNDS, leftToRight = true))
+    }
+
    fun mediaRecord(attachment: DatabaseAttachment?): MediaTable.MediaRecord {
      return MediaTable.MediaRecord(
        attachment = attachment,
@@ -0,0 +1,44 @@
+/*
+ * Copyright 2026 Signal Messenger, LLC
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+package org.signal.core.ui.compose
+
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.channels.Channel
+import kotlinx.coroutines.launch
+import org.signal.core.util.logging.Log
+
+/**
+ * Base presenter that helps one implement an Elm-like architecture, where events are processed and
+ * new models are emitted. In particular, this base class exists to setup the core event channel
+ * to avoid gotcha's around threading and race conditions.
+ */
+abstract class EventDrivenPresenter<E : Any>(
+  private val tag: String,
+  coroutineScope: CoroutineScope
+) {
+
+  private val eventChannel = Channel<E>(Channel.UNLIMITED)
+
+  init {
+    coroutineScope.launch {
+      for (event in eventChannel) {
+        Log.d(tag, "[Event] $event")
+        processEvent(event)
+      }
+    }
+  }
+
+  fun onEvent(event: E) {
+    // Unlimited buffer means this will always succeed
+    eventChannel.trySend(event)
+  }
+
+  /**
+   * Handle the event how you wish. It's recommended that you use the event to emit a new state model
+   * to be observed by the view.
+   */
+  protected abstract suspend fun processEvent(event: E)
+}
@@ -0,0 +1,23 @@
+plugins {
+  id("signal-library")
+  alias(libs.plugins.compose.compiler)
+}
+
+android {
+  namespace = "org.signal.uicomponents"
+
+  buildFeatures {
+    compose = true
+  }
+}
+
+dependencies {
+  lintChecks(project(":lintchecks"))
+
+  api(project(":core:ui"))
+
+  implementation(project(":lib:glide"))
+
+  implementation(platform(libs.androidx.compose.bom))
+  implementation(libs.androidx.compose.material3)
+}
@@ -0,0 +1,2 @@
+<?xml version="1.0" encoding="utf-8"?>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android" />
@@ -0,0 +1,124 @@
+/*
+ * Copyright 2026 Signal Messenger, LLC
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+package org.signal.uicomponents.recentmediarail
+
+import android.net.Uri
+import androidx.compose.foundation.background
+import androidx.compose.foundation.clickable
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.PaddingValues
+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.LazyRow
+import androidx.compose.foundation.lazy.itemsIndexed
+import androidx.compose.foundation.shape.RoundedCornerShape
+import androidx.compose.material3.MaterialTheme
+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.Modifier
+import androidx.compose.ui.draw.clip
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.layout.LayoutCoordinates
+import androidx.compose.ui.layout.boundsInWindow
+import androidx.compose.ui.layout.onGloballyPositioned
+import androidx.compose.ui.platform.LocalLayoutDirection
+import androidx.compose.ui.res.dimensionResource
+import androidx.compose.ui.unit.DpSize
+import androidx.compose.ui.unit.IntRect
+import androidx.compose.ui.unit.LayoutDirection
+import androidx.compose.ui.unit.dp
+import androidx.compose.ui.unit.roundToIntRect
+import org.signal.core.ui.compose.DayNightPreviews
+import org.signal.core.ui.compose.Previews
+import org.signal.glide.compose.GlideImage
+import org.signal.glide.compose.GlideImageScaleType
+import org.signal.glide.decryptableuri.DecryptableUri
+import org.signal.core.ui.R as CoreUiR
+
+private val ITEM_SIZE = 80.dp
+private val ITEM_SPACING = 8.dp
+private val ITEM_CORNERS = RoundedCornerShape(12.dp)
+private val ITEM_SCRIM = Color(0x14000000)
+
+/**
+ * A horizontally scrolling strip of media thumbnails, most recent first.
+ *
+ * Driven entirely by a [RecentMediaRailPresenter], which owns the state handed in here and decides what the events sent
+ * back out of here actually do.
+ */
+@Composable
+fun RecentMediaRail(
+  state: RecentMediaRailState,
+  onEvent: (RecentMediaRailEvents) -> Unit,
+  modifier: Modifier = Modifier
+) {
+  val leftToRight = LocalLayoutDirection.current == LayoutDirection.Ltr
+
+  LazyRow(
+    horizontalArrangement = Arrangement.spacedBy(ITEM_SPACING),
+    contentPadding = PaddingValues(horizontal = dimensionResource(CoreUiR.dimen.gutter)),
+    modifier = modifier
+      .fillMaxWidth()
+      .height(ITEM_SIZE)
+  ) {
+    itemsIndexed(state.media) { index, media ->
+      RecentMediaRailItem(
+        media = media,
+        onClick = { bounds -> onEvent(RecentMediaRailEvents.ItemClicked(index, bounds, leftToRight)) }
+      )
+    }
+  }
+}
+
+@Composable
+private fun RecentMediaRailItem(
+  media: RecentMedia,
+  onClick: (IntRect) -> Unit
+) {
+  var coordinates by remember { mutableStateOf<LayoutCoordinates?>(null) }
+
+  Box(
+    modifier = Modifier
+      .size(ITEM_SIZE)
+      .clip(ITEM_CORNERS)
+      .background(MaterialTheme.colorScheme.surfaceVariant)
+      .onGloballyPositioned { coordinates = it }
+      .clickable { onClick(coordinates?.boundsInWindow()?.roundToIntRect() ?: IntRect.Zero) }
+  ) {
+    GlideImage(
+      model = remember(media) { media.thumbnailUri?.let { DecryptableUri(it, media.thumbnailTimeUs) } },
+      imageSize = DpSize(ITEM_SIZE, ITEM_SIZE),
+      scaleType = GlideImageScaleType.CENTER_CROP,
+      modifier = Modifier.fillMaxSize()
+    )
+
+    Box(
+      modifier = Modifier
+        .fillMaxSize()
+        .background(ITEM_SCRIM)
+    )
+  }
+}
+
+@DayNightPreviews
+@Composable
+private fun RecentMediaRailPreview() {
+  Previews.Preview {
+    RecentMediaRail(
+      state = RecentMediaRailState(
+        media = List(5) { RecentMedia(thumbnailUri = Uri.EMPTY, availability = RecentMedia.Availability.AVAILABLE) },
+        loaded = true
+      ),
+      onEvent = {}
+    )
+  }
+}
@@ -0,0 +1,28 @@
+/*
+ * Copyright 2026 Signal Messenger, LLC
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+package org.signal.uicomponents.recentmediarail
+
+import androidx.compose.ui.unit.IntRect
+
+/**
+ * Side effects that can be emitted by [RecentMediaRailPresenter] that need to be handled by the user of the component.
+ *
+ * Every [index] is a position in [RecentMediaRailState.media].
+ */
+sealed interface RecentMediaRailAction {
+
+  /** Show the media the user tapped, animating out of [bounds] (window coordinates). */
+  data class OpenMedia(val index: Int, val bounds: IntRect, val leftToRight: Boolean) : RecentMediaRailAction
+
+  /** Download the media the user tapped, since it isn't on the device yet. */
+  data class DownloadMedia(val index: Int) : RecentMediaRailAction
+
+  /** Tell the user the media they tapped isn't available. */
+  data object ShowMediaUnavailable : RecentMediaRailAction
+
+  /** Open the full list of media this rail is a preview of. */
+  data object OpenAllMedia : RecentMediaRailAction
+}
@@ -0,0 +1,35 @@
+/*
+ * Copyright 2026 Signal Messenger, LLC
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+package org.signal.uicomponents.recentmediarail
+
+import androidx.compose.ui.unit.IntRect
+
+/**
+ * Everything a [RecentMediaRailPresenter] can be told, whether it came from the rail itself or from the screen hosting
+ * it.
+ *
+ * Reminder that these events are logged, so don't include anything sensitive in the toString.
+ */
+sealed interface RecentMediaRailEvents {
+
+  /** The rail has something to load from. Each distinct [sourceId] kicks off a fresh load. */
+  data class SourceChanged(val sourceId: Long) : RecentMediaRailEvents
+
+  /** Reload the current source, e.g. after the user came back from the media viewer. */
+  data object RefreshRequested : RecentMediaRailEvents
+
+  /**
+   * The user tapped an item.
+   *
+   * @param index Position in [RecentMediaRailState.media].
+   * @param bounds The item's bounds in window coordinates, for hosts that want to animate out of it.
+   * @param leftToRight Whether the rail was laid out left to right, which decides which way the media viewer pages.
+   */
+  data class ItemClicked(val index: Int, val bounds: IntRect, val leftToRight: Boolean) : RecentMediaRailEvents
+
+  /** The user asked to see everything the rail is a preview of. */
+  data object SeeAllClicked : RecentMediaRailEvents
+}
@@ -0,0 +1,83 @@
+/*
+ * Copyright 2026 Signal Messenger, LLC
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+package org.signal.uicomponents.recentmediarail
+
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.channels.Channel
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.flow.asStateFlow
+import kotlinx.coroutines.flow.receiveAsFlow
+import org.signal.core.ui.compose.EventDrivenPresenter
+import org.signal.core.util.logging.Log
+import org.signal.uicomponents.recentmediarail.RecentMedia.Availability
+
+/**
+ * All of the logic behind a [RecentMediaRail]: loading it, keeping it up to date, and deciding what a tap on it should
+ * do.
+ *
+ * Meant to be held by the view model of whichever screen shows the rail, which feeds it events, mirrors [state] into
+ * its own state, and carries out [actions].
+ */
+class RecentMediaRailPresenter(
+  coroutineScope: CoroutineScope,
+  private val loader: Loader
+) : EventDrivenPresenter<RecentMediaRailEvents>(TAG, coroutineScope) {
+
+  companion object {
+    private val TAG = Log.tag(RecentMediaRailPresenter::class)
+  }
+
+  private val _state = MutableStateFlow(RecentMediaRailState())
+  private val _actions = Channel<RecentMediaRailAction>(Channel.BUFFERED)
+
+  val state: StateFlow<RecentMediaRailState> = _state.asStateFlow()
+  val actions: Flow<RecentMediaRailAction> = _actions.receiveAsFlow()
+
+  private var sourceId: Long? = null
+
+  override suspend fun processEvent(event: RecentMediaRailEvents) {
+    when (event) {
+      is RecentMediaRailEvents.SourceChanged -> {
+        if (sourceId != event.sourceId) {
+          sourceId = event.sourceId
+          load()
+        }
+      }
+      RecentMediaRailEvents.RefreshRequested -> {
+        load()
+      }
+      is RecentMediaRailEvents.ItemClicked -> {
+        val media = _state.value.media.getOrNull(event.index)
+
+        val action = when (media?.availability) {
+          Availability.AVAILABLE -> RecentMediaRailAction.OpenMedia(event.index, event.bounds, event.leftToRight)
+          Availability.RESTORABLE -> RecentMediaRailAction.DownloadMedia(event.index)
+          Availability.UNAVAILABLE -> RecentMediaRailAction.ShowMediaUnavailable
+          null -> null
+        }
+
+        if (action != null) {
+          _actions.send(action)
+        }
+      }
+      RecentMediaRailEvents.SeeAllClicked -> {
+        _actions.send(RecentMediaRailAction.OpenAllMedia)
+      }
+    }
+  }
+
+  private suspend fun load() {
+    val id = sourceId ?: return
+    _state.value = RecentMediaRailState(media = loader.load(id), loaded = true)
+  }
+
+  /** Where the rail's contents come from. */
+  fun interface Loader {
+    suspend fun load(sourceId: Long): List<RecentMedia>
+  }
+}
@@ -0,0 +1,46 @@
+/*
+ * Copyright 2026 Signal Messenger, LLC
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+package org.signal.uicomponents.recentmediarail
+
+import android.net.Uri
+
+/**
+ * State of a [RecentMediaRail]. Owned by a [RecentMediaRailPresenter] and expected to be mirrored into the state of
+ * whatever screen the rail sits in.
+ */
+data class RecentMediaRailState(
+  val media: List<RecentMedia> = emptyList(),
+  val loaded: Boolean = false
+) {
+
+  /**
+   * Whether the rail belongs in the layout at all. It stays put while [loaded] is false so that media arriving later
+   * fills space that was already there instead of shoving the rest of the screen down, and is only dropped once we know
+   * there's nothing to show.
+   */
+  val visible: Boolean = !loaded || media.isNotEmpty()
+}
+
+/** A single thumbnail in a [RecentMediaRail]. */
+data class RecentMedia(
+  val thumbnailUri: Uri?,
+  val availability: Availability,
+  /** Which frame of a video the thumbnail should show, for media that was trimmed before it was sent. */
+  val thumbnailTimeUs: Long = 0
+) {
+
+  /** Whether tapping an item can show it, and if not, what to do instead. */
+  enum class Availability {
+    /** On the device and ready to view. */
+    AVAILABLE,
+
+    /** Offloaded, and needs to be downloaded before it can be viewed. */
+    RESTORABLE,
+
+    /** Not here, and not something we can go get. */
+    UNAVAILABLE
+  }
+}
@@ -124,6 +124,7 @@ include(":lib:blurhash")
 include(":lib:apng")
 include(":lib:emoji")
 include(":lib:archive")
+include(":lib:ui-components")

 // Feature modules
 include(":feature:registration")