From d76c80a63100b54f6da970705d412164cb952a07 Mon Sep 17 00:00:00 2001 From: nixzhu Date: Wed, 8 Jul 2015 12:26:30 +0800 Subject: [PATCH] border condition of delete message --- .../ConversationViewController.swift | 21 +++++++++++++++---- 1 file changed, 17 insertions(+), 4 deletions(-) diff --git a/Yep/ViewControllers/Conversation/ConversationViewController.swift b/Yep/ViewControllers/Conversation/ConversationViewController.swift index 130c5042..986e980f 100644 --- a/Yep/ViewControllers/Conversation/ConversationViewController.swift +++ b/Yep/ViewControllers/Conversation/ConversationViewController.swift @@ -2102,7 +2102,11 @@ extension ConversationViewController: UICollectionViewDataSource, UICollectionVi var sectionDateMessage: Message? if let currentMessageIndex = strongSelf.messages.indexOf(message) { - if let previousMessage = strongSelf.messages[safe: currentMessageIndex - 1] { + + let previousMessageIndex = currentMessageIndex - 1 + + if let previousMessage = strongSelf.messages[safe: previousMessageIndex] { + if previousMessage.mediaType == MessageMediaType.SectionDate.rawValue { sectionDateMessage = previousMessage } @@ -2110,15 +2114,24 @@ extension ConversationViewController: UICollectionViewDataSource, UICollectionVi } if let sectionDateMessage = sectionDateMessage { - strongSelf.displayedMessagesRange.length -= 2 + + var canDeleteTwoMessages = false // 考虑刚好的边界情况，例如消息为本束的最后一条，而 sectionDate 在上一束中 + if strongSelf.displayedMessagesRange.length >= 2 { + strongSelf.displayedMessagesRange.length -= 2 + canDeleteTwoMessages = true + } realm.write { realm.delete(sectionDateMessage) realm.delete(message) } - let previousIndexPath = NSIndexPath(forItem: indexPath.item - 1, inSection: indexPath.section) - strongSelf.conversationCollectionView.deleteItemsAtIndexPaths([previousIndexPath, indexPath]) + if canDeleteTwoMessages { + let previousIndexPath = NSIndexPath(forItem: indexPath.item - 1, inSection: indexPath.section) + strongSelf.conversationCollectionView.deleteItemsAtIndexPaths([previousIndexPath, indexPath]) + } else { + strongSelf.conversationCollectionView.deleteItemsAtIndexPaths([indexPath]) + } } else { strongSelf.displayedMessagesRange.length -= 1