Merge pull request #528 from badoo/lazy_initialization_of_builders

Creation of a presenter factory is postponed until it's needed for it…
badoo · Nov 7, 2018 · 6c33413 · 6c33413
2 parents aa67bac + 7cbac82
commit 6c33413
Showing 3 changed files with 25 additions and 13 deletions.
diff --git a/Chatto/Source/ChatController/BaseChatViewController+Changes.swift b/Chatto/Source/ChatController/BaseChatViewController+Changes.swift
@@ -24,15 +24,7 @@
 
 import Foundation
 
-extension BaseChatViewController: ChatDataSourceDelegateProtocol {
-
-    public func chatDataSourceDidUpdate(_ chatDataSource: ChatDataSourceProtocol, updateType: UpdateType) {
-        self.enqueueModelUpdate(updateType: updateType)
-    }
-
-    public func chatDataSourceDidUpdate(_ chatDataSource: ChatDataSourceProtocol) {
-        self.enqueueModelUpdate(updateType: .normal)
-    }
+extension BaseChatViewController {    
 
     public func enqueueModelUpdate(updateType: UpdateType) {
         let newItems = self.chatDataSource?.chatItems ?? []

diff --git a/Chatto/Source/ChatController/BaseChatViewController+Presenters.swift b/Chatto/Source/ChatController/BaseChatViewController+Presenters.swift
@@ -117,9 +117,16 @@ extension BaseChatViewController: ChatCollectionViewLayoutDelegate {
     }
 
     public func createPresenterForChatItem(_ chatItem: ChatItemProtocol) -> ChatItemPresenterProtocol {
+        assert(self.presenterFactory != nil, "Presenter factory is not initialized")
         return self.presenterFactory.createChatItemPresenter(chatItem)
     }
 
+    public func confugureCollectionViewWithPresenters() {
+        assert(self.presenterFactory == nil, "Presenter factory is already initialized")
+        self.presenterFactory = self.createPresenterFactory()
+        self.presenterFactory.configure(withCollectionView: self.collectionView)
+    }
+
     public func decorationAttributesForIndexPath(_ indexPath: IndexPath) -> ChatItemDecorationAttributesProtocol? {
         return self.chatItemCompanionCollection[indexPath.item].decorationAttributes
     }

diff --git a/Chatto/Source/ChatController/BaseChatViewController.swift b/Chatto/Source/ChatController/BaseChatViewController.swift
@@ -24,7 +24,7 @@
 
 import UIKit
 
-open class BaseChatViewController: UIViewController, UICollectionViewDataSource, UICollectionViewDelegate {
+open class BaseChatViewController: UIViewController, UICollectionViewDataSource, UICollectionViewDelegate, ChatDataSourceDelegateProtocol {
 
     public typealias ChatItemCompanionCollection = ReadOnlyOrderedDictionary<ChatItemCompanion>
 
@@ -50,6 +50,8 @@ open class BaseChatViewController: UIViewController, UICollectionViewDataSource,
 
     public var updatesConfig =  UpdatesConfig()
 
+    open var customPresentersConfigurationPoint = false // If true then confugureCollectionViewWithPresenters() will not be called in viewDidLoad() method and has to be called manually
+
     public private(set) var collectionView: UICollectionView!
     public final internal(set) var chatItemCompanionCollection: ChatItemCompanionCollection = ReadOnlyOrderedDictionary(items: [])
     private var _chatDataSource: ChatDataSourceProtocol?
@@ -152,8 +154,9 @@ open class BaseChatViewController: UIViewController, UICollectionViewDataSource,
 
         self.accessoryViewRevealer = AccessoryViewRevealer(collectionView: self.collectionView)
 
-        self.presenterFactory = self.createPresenterFactory()
-        self.presenterFactory.configure(withCollectionView: self.collectionView)
+        if !self.customPresentersConfigurationPoint {
+            self.confugureCollectionViewWithPresenters()
+        }
     }
 
     var unfinishedBatchUpdatesCount: Int = 0
@@ -325,7 +328,7 @@ open class BaseChatViewController: UIViewController, UICollectionViewDataSource,
     var accessoryViewRevealer: AccessoryViewRevealer!
     public private(set) var inputContainer: UIView!
     public private(set) var bottomSpaceView: UIView!
-    var presenterFactory: ChatItemPresenterFactoryProtocol!
+    public internal(set) var presenterFactory: ChatItemPresenterFactoryProtocol!
     let presentersByCell = NSMapTable<UICollectionViewCell, AnyObject>(keyOptions: .weakMemory, valueOptions: .weakMemory)
     var visibleCells: [IndexPath: UICollectionViewCell] = [:] // @see visibleCellsAreValid(changes:)
 
@@ -372,6 +375,16 @@ open class BaseChatViewController: UIViewController, UICollectionViewDataSource,
         let firstItemMoved = changes.movedIndexPaths.first
         return (firstItemMoved?.indexPathOld as IndexPath?, firstItemMoved?.indexPathNew as IndexPath?)
     }
+
+    // MARK: ChatDataSourceDelegateProtocol
+
+    open func chatDataSourceDidUpdate(_ chatDataSource: ChatDataSourceProtocol, updateType: UpdateType) {
+        self.enqueueModelUpdate(updateType: updateType)
+    }
+
+    open func chatDataSourceDidUpdate(_ chatDataSource: ChatDataSourceProtocol) {
+        self.enqueueModelUpdate(updateType: .normal)
+    }
 }
 
 extension BaseChatViewController { // Rotation