fix a race condition with interactive transition

HeroTransitions · Feb 12, 2017 · f71d664 · f71d664
1 parent f57b79e
commit f71d664
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Showing 2 changed files with 7 additions and 27 deletions.
diff --git a/Sources/Hero.swift b/Sources/Hero.swift
@@ -177,9 +177,9 @@ internal extension Hero {
       animate()
     #else
       if inNavigationController {
-        // When animating within navigationController, we have to delay a frame.
-        // otherwise snapshots will not be taken. Possibly a bug with UIKit
-        execute(after: 0.01666666667) {
+        // When animating within navigationController, we have to dispatch later into the main queue.
+        // otherwise snapshots will be pure white. Possibly a bug with UIKit
+        DispatchQueue.main.async {
           self.animate()
         }
       } else {

diff --git a/Sources/HeroBaseController.swift b/Sources/HeroBaseController.swift
@@ -22,13 +22,6 @@
 
 import UIKit
 
-internal var heroOperationQueue: OperationQueue = {
-  let oq = OperationQueue()
-  oq.maxConcurrentOperationCount = 1
-  oq.name = "heroOperationQueue"
-  return oq
-}()
-
 /// Base class for managing a Hero transition
 public class HeroBaseController: NSObject {
   // MARK: Properties
@@ -143,7 +136,7 @@ public extension HeroBaseController {
    */
   public func update(progress: Double) {
     guard transitioning else { return }
-    execute {
+    DispatchQueue.main.async {
       self.beginTime = nil
       self.progress = max(0, min(1, progress))
     }
@@ -156,7 +149,7 @@ public extension HeroBaseController {
    */
   public func end(animate: Bool = true) {
     guard transitioning && interactive else { return }
-    execute {
+    DispatchQueue.main.async {
       if !animate {
         self.complete(finished:true)
         return
@@ -177,7 +170,7 @@ public extension HeroBaseController {
    */
   public func cancel(animate: Bool = true) {
     guard transitioning && interactive else { return }
-    execute {
+    DispatchQueue.main.async {
       if !animate {
         self.complete(finished:false)
         return
@@ -205,7 +198,7 @@ public extension HeroBaseController {
    */
   public func apply(modifiers: [HeroModifier], to view: UIView) {
     guard transitioning && interactive else { return }
-    execute {
+    DispatchQueue.main.async {
       let targetState = HeroTargetState(modifiers: modifiers)
       if let otherView = self.context.pairedView(for: view) {
         for animator in self.animators {
@@ -372,19 +365,6 @@ internal extension HeroBaseController {
 
     completion?(finished)
   }
-
-  func execute(after: TimeInterval = 0, block: @escaping () -> Void) {
-    if heroOperationQueue.operationCount > 0 || after > 0 {
-      heroOperationQueue.addOperation {
-        Thread.sleep(forTimeInterval: after)
-        DispatchQueue.main.async {
-          block()
-        }
-      }
-    } else {
-      block()
-    }
-  }
 }
 
 // MARK: Plugin Support