From bd7e9b5943a9ff779e4c66e1ede0aca4eaa189d9 Mon Sep 17 00:00:00 2001
From: ryanzhao <ryanzhaors@qq.com>
Date: Tue, 20 Jul 2021 11:46:02 +1000
Subject: [PATCH] add comment

---
 Session/Conversations/ConversationVC.swift | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/Session/Conversations/ConversationVC.swift b/Session/Conversations/ConversationVC.swift
index 45cf5b7ce..baa5ec147 100644
--- a/Session/Conversations/ConversationVC.swift
+++ b/Session/Conversations/ConversationVC.swift
@@ -222,6 +222,10 @@ final class ConversationVC : BaseVC, ConversationViewModelDelegate, OWSConversat
             Storage.read { transaction in
                 unreadCount = self.thread.unreadMessageCount(transaction: transaction)
             }
+            // When the unread message count is more than the number of a page of viewItems,
+            // the screen will scroll to bottom instead of the correct first unread message.
+            // The unreadIndicatorIndex is calculated during loading the viewItems, it is
+            // supposed to be accurate.
             DispatchQueue.main.async {
                 let unreadIndicatorIndex = self.viewModel.viewState.unreadIndicatorIndex?.intValue ?? (self.viewItems.count - self.unreadViewItems.count)
                 if unreadCount > 0, let viewItem = self.viewItems[ifValid: unreadIndicatorIndex], let interactionID = viewItem.interaction.uniqueId {