Merge pull request #202 from uias/feature/fix-indexmap

Fix issue where index map could have invalid keys
uias · Mar 3, 2019 · ab4e2ad · ab4e2ad
2 parents 075add4 + 41b3d5e
commit ab4e2ad
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Showing 4 changed files with 15 additions and 20 deletions.
diff --git a/Sources/Pageboy.xcodeproj/project.pbxproj b/Sources/Pageboy.xcodeproj/project.pbxproj
@@ -8,7 +8,7 @@
 
 /* Begin PBXBuildFile section */
  460906B7222A785E005474BF /* WeakContainer.swift in Sources */ = {isa = PBXBuildFile; fileRef = 460906B6222A785E005474BF /* WeakContainer.swift */; };
- 460906B9222A79F6005474BF /* ObjectIndexMap.swift in Sources */ = {isa = PBXBuildFile; fileRef = 460906B8222A79F6005474BF /* ObjectIndexMap.swift */; };
+ 460906B9222A79F6005474BF /* IndexedObjectMap.swift in Sources */ = {isa = PBXBuildFile; fileRef = 460906B8222A79F6005474BF /* IndexedObjectMap.swift */; };
  461D6DF1201795A100E0CDEE /* UIScrollView+ScrollActivity.swift in Sources */ = {isa = PBXBuildFile; fileRef = 461D6DF0201795A100E0CDEE /* UIScrollView+ScrollActivity.swift */; };
  461D6DF2201795A100E0CDEE /* UIScrollView+ScrollActivity.swift in Sources */ = {isa = PBXBuildFile; fileRef = 461D6DF0201795A100E0CDEE /* UIScrollView+ScrollActivity.swift */; };
  462A65DD2000FCAA0051C79C /* UIView+Localization.swift in Sources */ = {isa = PBXBuildFile; fileRef = 462A65D92000FCAA0051C79C /* UIView+Localization.swift */; };
@@ -79,7 +79,7 @@
 
 /* Begin PBXFileReference section */
  460906B6222A785E005474BF /* WeakContainer.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = WeakContainer.swift; sourceTree = "<group>"; };
- 460906B8222A79F6005474BF /* ObjectIndexMap.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ObjectIndexMap.swift; sourceTree = "<group>"; };
+ 460906B8222A79F6005474BF /* IndexedObjectMap.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = IndexedObjectMap.swift; sourceTree = "<group>"; };
  461D6DF0201795A100E0CDEE /* UIScrollView+ScrollActivity.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "UIScrollView+ScrollActivity.swift"; sourceTree = "<group>"; };
  462A65D92000FCAA0051C79C /* UIView+Localization.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = "UIView+Localization.swift"; sourceTree = "<group>"; };
  462A65DA2000FCAA0051C79C /* UIView+AutoLayout.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = "UIView+AutoLayout.swift"; sourceTree = "<group>"; };
@@ -277,7 +277,7 @@
  children = (
  462A65D82000FCAA0051C79C /* Extensions */,
  460906B6222A785E005474BF /* WeakContainer.swift */,
- 460906B8222A79F6005474BF /* ObjectIndexMap.swift */,
+ 460906B8222A79F6005474BF /* IndexedObjectMap.swift */,
  );
  path = Utilities;
  sourceTree = "<group>";
@@ -492,7 +492,7 @@
  464ADF552097565D00929AFB /* Page.swift in Sources */,
  46ADAAB8208F7E1500974529 /* PageboyViewController+AutoScrolling.swift in Sources */,
  462A65E32000FCAA0051C79C /* UIPageViewController+ScrollView.swift in Sources */,
- 460906B9222A79F6005474BF /* ObjectIndexMap.swift in Sources */,
+ 460906B9222A79F6005474BF /* IndexedObjectMap.swift in Sources */,
  46ADAAC2208F7E8500974529 /* TransitionOperation.swift in Sources */,
  461D6DF1201795A100E0CDEE /* UIScrollView+ScrollActivity.swift in Sources */,
  462A65DF2000FCAA0051C79C /* UIView+AutoLayout.swift in Sources */,

diff --git a/Sources/Pageboy/PageboyViewController.swift b/Sources/Pageboy/PageboyViewController.swift
@@ -138,7 +138,7 @@ open class PageboyViewController: UIViewController {
  /// The number of view controllers in the page view controller.
  internal var viewControllerCount: Int?
  /// A map of view controllers and related page indexes.
- internal lazy var viewControllerIndexMap = ObjectIndexMap<UIViewController>()
+ internal lazy var viewControllerIndexMap = IndexedObjectMap<UIViewController>()
 
  /// The number of pages in the page view controller.
  public var pageCount: Int? {

diff --git a/...es/Pageboy/Utilities/ObjectIndexMap.swift → .../Pageboy/Utilities/IndexedObjectMap.swift b/...es/Pageboy/Utilities/ObjectIndexMap.swift → .../Pageboy/Utilities/IndexedObjectMap.swift
@@ -8,18 +8,18 @@
 
 import Foundation
 
-/// Map which stores an index next to an object.
-internal final class ObjectIndexMap<T: AnyObject> {
+/// Map which weakly stores an object for an index key.
+internal final class IndexedObjectMap<T: AnyObject> {
 
  // MARK: Properties
 
- private var map = [WeakWrapper<T>: Int]()
+ private var map = [Int: WeakWrapper<T>]()
 
  // MARK: Accessors
 
  func index(for object: T) -> Int? {
  cleanUp()
- return map.first(where: { $0.key.object === object })?.value
+ return map.first(where: { $0.value.object === object })?.key
  }
 
  // MARK: Mutators
@@ -28,20 +28,20 @@ internal final class ObjectIndexMap<T: AnyObject> {
  cleanUp()
 
  let wrapper = WeakWrapper<T>(object)
- map[wrapper] = index
+ map[index] = wrapper
  }
 
  func removeAll() {
  map.removeAll()
  }
 
  private func cleanUp() {
- var invalidObjects = [WeakWrapper<T>]()
+ var invalidIndexes = [Int]()
  map.forEach({
- if $0.key.object == nil {
- invalidObjects.append($0.key)
+ if $0.value.object == nil {
+ invalidIndexes.append($0.key)
  }
  })
- invalidObjects.forEach({ self.map[$0] = nil })
+ invalidIndexes.forEach({ self.map[$0] = nil })
  }
 }
diff --git a/Sources/Pageboy/Utilities/WeakContainer.swift b/Sources/Pageboy/Utilities/WeakContainer.swift
@@ -11,20 +11,15 @@ import Foundation
 internal final class WeakWrapper<T: AnyObject> {
 
  private(set) weak var object: T?
- private let uuid = UUID().uuidString
 
  init(_ object: T) {
  self.object = object
  }
 }
 
-extension WeakWrapper: Hashable {
+extension WeakWrapper: Equatable {
 
  static func == (lhs: WeakWrapper, rhs: WeakWrapper) -> Bool {
  return lhs.object === rhs.object
  }
-
- func hash(into hasher: inout Hasher) {
- hasher.combine(uuid.hashValue)
- }
 }