From f3441de08be51228dc5cd0b2b44b35baa5aa7a39 Mon Sep 17 00:00:00 2001
From: nixzhu <zhuhongxu@gmail.com>
Date: Mon, 13 Apr 2015 20:05:50 +0800
Subject: [PATCH] fix updateConversationCollectionView after send message, use
 lastDisplayedMessagesRange for new message's indexPath

---
 .../Conversation/ConversationViewController.swift         | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/Yep/ViewControllers/Conversation/ConversationViewController.swift b/Yep/ViewControllers/Conversation/ConversationViewController.swift
index d9e84e94..77c45e85 100644
--- a/Yep/ViewControllers/Conversation/ConversationViewController.swift
+++ b/Yep/ViewControllers/Conversation/ConversationViewController.swift
@@ -504,13 +504,15 @@ class ConversationViewController: UIViewController {
         if messages.count <= _lastTimeMessagesCount {
             return
         }
-        let newMessagesCount = messages.count - _lastTimeMessagesCount
+        let newMessagesCount = Int(messages.count - _lastTimeMessagesCount)
 
-        displayedMessagesRange.length += Int(newMessagesCount)
+        let lastDisplayedMessagesRange = displayedMessagesRange
+
+        displayedMessagesRange.length += newMessagesCount
 
         var indexPaths = [NSIndexPath]()
         for i in 0..<newMessagesCount {
-            let indexPath = NSIndexPath(forItem: displayedMessagesRange.length - 1 + Int(i), inSection: 0)
+            let indexPath = NSIndexPath(forItem: lastDisplayedMessagesRange.length + i, inSection: 0)
             indexPaths.append(indexPath)
         }