Fix LocationMessageCell reuse bug

CHANGELOG.md

@@ -6,6 +6,11 @@ The changelog for `MessageKit`. Also see the [releases](https://github.com/Messa
 
 ## Upcoming release
 
+### Fixed
+
+- Fixed `LocationMessageCell` reuse bug, to avoid inconsistency when get capture image asynchronously. 
+[#428](https://github.com/MessageKit/MessageKit/pull/428) by [@zhongwuzw](https://github.com/zhongwuzw).
+
 ## [[Prerelease] 0.12.0](https://github.com/MessageKit/MessageKit/releases/tag/0.12.0)
 
 ### Added

Sources/Views/Cells/LocationMessageCell.swift

@@ -34,6 +34,8 @@ open class LocationMessageCell: MessageCollectionViewCell {
     open var activityIndicator = UIActivityIndicatorView(activityIndicatorStyle: .gray)
 
     open var imageView = UIImageView()
+    
+    private weak var snapShotter: MKMapSnapshotter?
 
     open override func setupSubviews() {
         super.setupSubviews()
@@ -47,6 +49,11 @@ open class LocationMessageCell: MessageCollectionViewCell {
         imageView.fillSuperview()
         activityIndicator.centerInSuperview()
     }
+    
+    open override func prepareForReuse() {
+        super.prepareForReuse()
+        snapShotter?.cancel()
+    }
 
     open override func configure(with message: MessageType, at indexPath: IndexPath, and messagesCollectionView: MessagesCollectionView) {
         super.configure(with: message, at: indexPath, and: messagesCollectionView)
@@ -67,6 +74,7 @@ open class LocationMessageCell: MessageCollectionViewCell {
         snapshotOptions.showsPointsOfInterest = options.showsPointsOfInterest
 
         let snapShotter = MKMapSnapshotter(options: snapshotOptions)
+        self.snapShotter = snapShotter
         snapShotter.start { (snapshot, error) in
             defer {
                 self.activityIndicator.stopAnimating()