Merge pull request #483 from malmazuke/disable-scroll

Disable table view scroll when swiping to reply in a conversation

Session/Conversations/ConversationVC+Interaction.swift

@@ -468,6 +468,15 @@ extension ConversationVC : InputViewDelegate, MessageCellDelegate, ContextMenuAc
             }
         }
     }
+    
+    func handleViewItemSwiped(_ viewItem: ConversationViewItem, state: SwipeState) {
+        switch state {
+        case .began:
+            messagesTableView.isScrollEnabled = false
+        case .ended, .cancelled:
+            messagesTableView.isScrollEnabled = true
+        }
+    }
 
     func showFailedMessageSheet(for tsMessage: TSOutgoingMessage) {
         let thread = self.thread

Session/Conversations/Message Cells/MessageCell.swift

@@ -1,5 +1,11 @@
 import UIKit
 
+public enum SwipeState {
+    case began
+    case ended
+    case cancelled
+}
+
 class MessageCell : UITableViewCell {
     weak var delegate: MessageCellDelegate?
     var viewItem: ConversationViewItem? { didSet { update() } }
@@ -55,6 +61,7 @@ protocol MessageCellDelegate : AnyObject {
     func handleViewItemLongPressed(_ viewItem: ConversationViewItem)
     func handleViewItemTapped(_ viewItem: ConversationViewItem, gestureRecognizer: UITapGestureRecognizer)
     func handleViewItemDoubleTapped(_ viewItem: ConversationViewItem)
+    func handleViewItemSwiped(_ viewItem: ConversationViewItem, state: SwipeState)
     func showFullText(_ viewItem: ConversationViewItem)
     func openURL(_ url: URL)
     func handleReplyButtonTapped(for viewItem: ConversationViewItem)

Session/Conversations/Message Cells/VisibleMessageCell.swift

@@ -466,9 +466,12 @@ final class VisibleMessageCell : MessageCell, LinkPreviewViewDelegate {
     }
     
     @objc private func handlePan(_ gestureRecognizer: UIPanGestureRecognizer) {
+        guard let viewItem = viewItem else { return }
         let viewsToMove = [ bubbleView, profilePictureView, replyButton, timerView, messageStatusImageView ]
         let translationX = gestureRecognizer.translation(in: self).x.clamp(-CGFloat.greatestFiniteMagnitude, 0)
         switch gestureRecognizer.state {
+        case .began:
+            delegate?.handleViewItemSwiped(viewItem, state: .began)
         case .changed:
             // The idea here is to asymptotically approach a maximum drag distance
             let damping: CGFloat = 20
@@ -486,8 +489,10 @@ final class VisibleMessageCell : MessageCell, LinkPreviewViewDelegate {
             previousX = translationX
         case .ended, .cancelled:
             if abs(translationX) > VisibleMessageCell.swipeToReplyThreshold {
+                delegate?.handleViewItemSwiped(viewItem, state: .ended)
                 reply()
             } else {
+                delegate?.handleViewItemSwiped(viewItem, state: .cancelled)
                 resetReply()
             }
         default: break