Don't update cell if model didn't change

appsailor · Feb 5, 2019 · 80dd088 · 80dd088
1 parent a4839c9
commit 80dd088
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Showing 4 changed files with 21 additions and 8 deletions.
diff --git a/ChattoAdditions/Source/Chat Items/CompoundMessage/CompoundMessagePresenter.swift b/ChattoAdditions/Source/Chat Items/CompoundMessage/CompoundMessagePresenter.swift
@@ -27,6 +27,7 @@ import Chatto
 public final class CompoundMessagePresenter<ViewModelBuilderT, InteractionHandlerT>
     : BaseMessagePresenter<CompoundBubbleView, ViewModelBuilderT, InteractionHandlerT> where
     ViewModelBuilderT: ViewModelBuilderProtocol,
+    ViewModelBuilderT.ModelT: Equatable,
     InteractionHandlerT: BaseMessageInteractionHandlerProtocol,
     InteractionHandlerT.ViewModelT == ViewModelBuilderT.ViewModelT {
 
@@ -43,7 +44,7 @@ public final class CompoundMessagePresenter<ViewModelBuilderT, InteractionHandle
         viewModelBuilder: ViewModelBuilderT,
         interactionHandler: InteractionHandlerT?,
         contentFactories: [AnyMessageContentFactory<ModelT>],
-        sizingCell: CompoundMessageCollectionViewCell,
+        sizingCell: CompoundMessageCollectionViewCell<ModelT>,
         baseCellStyle: BaseMessageCollectionViewCellStyleProtocol,
         compoundCellStyle: CompoundBubbleViewStyleProtocol,
         cache: Cache<CompoundBubbleLayoutProvider.Configuration, CompoundBubbleLayoutProvider>
@@ -65,7 +66,7 @@ public final class CompoundMessagePresenter<ViewModelBuilderT, InteractionHandle
     }
 
     public override class func registerCells(_ collectionView: UICollectionView) {
-        collectionView.register(CompoundMessageCollectionViewCell.self,
+        collectionView.register(CompoundMessageCollectionViewCell<ModelT>.self,
                                 forCellWithReuseIdentifier: .compoundCellReuseId)
     }
 
@@ -85,12 +86,14 @@ public final class CompoundMessagePresenter<ViewModelBuilderT, InteractionHandle
                                        decorationAttributes: ChatItemDecorationAttributes,
                                        animated: Bool,
                                        additionalConfiguration: (() -> Void)?) {
-        guard let compoundCell = cell as? CompoundMessageCollectionViewCell else {
-            assertionFailure("\(cell) is not CompoundMessageCollectionViewCell")
+        guard let compoundCell = cell as? CompoundMessageCollectionViewCell<ModelT> else {
+            assertionFailure("\(cell) is not CompoundMessageCollectionViewCell<\(ModelT.self)>")
             return
         }
 
-        super.configureCell(cell, decorationAttributes: decorationAttributes, animated: animated) {
+        super.configureCell(compoundCell, decorationAttributes: decorationAttributes, animated: animated) {
+            guard compoundCell.lastDisplayedModel != self.messageModel else { return }
+            compoundCell.lastDisplayedModel = self.messageModel
             let modules = self.contentFactories.map { $0.createMessageModule(forModel: self.messageModel) }
             let bubbleView = compoundCell.bubbleView!
             let borderedViewIndexes = modules.enumerated().compactMap { index, module in

diff --git a/ChattoAdditions/Source/Chat Items/CompoundMessage/CompoundMessagePresenterBuilder.swift b/ChattoAdditions/Source/Chat Items/CompoundMessage/CompoundMessagePresenterBuilder.swift
@@ -26,6 +26,7 @@ import Chatto
 @available(iOS 11, *)
 public final class CompoundMessagePresenterBuilder<ViewModelBuilderT, InteractionHandlerT>: ChatItemPresenterBuilderProtocol where
     ViewModelBuilderT: ViewModelBuilderProtocol,
+    ViewModelBuilderT.ModelT: Equatable,
     InteractionHandlerT: BaseMessageInteractionHandlerProtocol,
     InteractionHandlerT.ViewModelT == ViewModelBuilderT.ViewModelT {
     public typealias ModelT = ViewModelBuilderT.ModelT
@@ -43,7 +44,7 @@ public final class CompoundMessagePresenterBuilder<ViewModelBuilderT, Interactio
     public let viewModelBuilder: ViewModelBuilderT
     public let interactionHandler: InteractionHandlerT?
     private let contentFactories: [AnyMessageContentFactory<ModelT>]
-    public let sizingCell: CompoundMessageCollectionViewCell = CompoundMessageCollectionViewCell()
+    public let sizingCell: CompoundMessageCollectionViewCell = CompoundMessageCollectionViewCell<ModelT>()
     public lazy var compoundCellStyle: CompoundBubbleViewStyleProtocol = DefaultCompoundBubbleViewStyle()
     public lazy var baseCellStyle: BaseMessageCollectionViewCellStyleProtocol = BaseMessageCollectionViewCellDefaultStyle()
     private let cache = Cache<CompoundBubbleLayoutProvider.Configuration, CompoundBubbleLayoutProvider>()

diff --git a/...Additions/Source/Chat Items/CompoundMessage/Views/CompoundMessageCollectionViewCell.swift b/...Additions/Source/Chat Items/CompoundMessage/Views/CompoundMessageCollectionViewCell.swift
@@ -22,7 +22,8 @@
 // THE SOFTWARE.
 
 @available(iOS 11, *)
-public final class CompoundMessageCollectionViewCell: BaseMessageCollectionViewCell<CompoundBubbleView> {
+public final class CompoundMessageCollectionViewCell<Model: Equatable>: BaseMessageCollectionViewCell<CompoundBubbleView> {
+    var lastDisplayedModel: Model?
     public override func createBubbleView() -> CompoundBubbleView! {
         return CompoundBubbleView()
     }

diff --git a/ChattoApp/ChattoApp/Source/Chat Items/Compound Messages/DemoCompoundMessageModel.swift b/ChattoApp/ChattoApp/Source/Chat Items/Compound Messages/DemoCompoundMessageModel.swift
@@ -23,7 +23,7 @@
 
 import ChattoAdditions
 
-final class DemoCompoundMessageModel: DecoratedMessageModelProtocol, DemoMessageModelProtocol {
+final class DemoCompoundMessageModel: Equatable, DecoratedMessageModelProtocol, DemoMessageModelProtocol {
 
     // MARK: - Instantiation
 
@@ -47,4 +47,12 @@ final class DemoCompoundMessageModel: DecoratedMessageModelProtocol, DemoMessage
 
     var status: MessageStatus
 
+    // MARK: - Equatable
+
+    static func == (lhs: DemoCompoundMessageModel, rhs: DemoCompoundMessageModel) -> Bool {
+        return lhs.text == rhs.text
+            && lhs.image == rhs.image
+            && lhs.messageModel.uid == rhs.messageModel.uid
+            && lhs.status == rhs.status
+    }
 }