less force unwrap

HeroTransitions · Jul 18, 2017 · d8c9443 · d8c9443
1 parent c5a510f
commit d8c9443
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Showing 3 changed files with 16 additions and 15 deletions.
diff --git a/Sources/Extensions/UIView+Hero.swift b/Sources/Extensions/UIView+Hero.swift
@@ -91,18 +91,19 @@ public extension UIView {
     return snapshotView
   }
 
-  internal func snapshotView() -> UIView {
-    var snapshot = snapshotView(afterScreenUpdates: true)!
-    if #available(iOS 11.0, *) {
+  internal func snapshotView() -> UIView? {
+    let snapshot = snapshotView(afterScreenUpdates: true)
+    if #available(iOS 11.0, *), let oldSnapshot = snapshot {
       // in iOS 11, the snapshot taken by snapshotView(afterScreenUpdates) won't contain a container view
-      let oldSnapshot = snapshot
-      snapshot = UIView()
-      snapshot.bounds = oldSnapshot.bounds
-      snapshot.center = oldSnapshot.center
-      oldSnapshot.center = snapshot.bounds.center
-      snapshot.addSubview(oldSnapshot)
+      let wrappedSnapshot = UIView()
+      wrappedSnapshot.bounds = oldSnapshot.bounds
+      wrappedSnapshot.center = oldSnapshot.center
+      oldSnapshot.center = wrappedSnapshot.bounds.center
+      wrappedSnapshot.addSubview(oldSnapshot)
+      return wrappedSnapshot
+    } else {
+      return snapshot
     }
-    return snapshot
   }
 
   internal var flattenedViewHierarchy: [UIView] {

diff --git a/Sources/HeroContext.swift b/Sources/HeroContext.swift
@@ -144,12 +144,12 @@ extension HeroContext {
     view.layer.cornerRadius = 0
     view.alpha = 1
 
-    var snapshot: UIView!
+    let snapshot: UIView
     let snapshotType: HeroSnapshotType = self[view]?.snapshotType ?? .optimized
 
     switch snapshotType {
     case .normal:
-      snapshot = view.snapshotView()
+      snapshot = view.snapshotView() ?? UIView()
     case .layerRender:
       snapshot = view.slowSnapshotView()
     case .noSnapshot:
@@ -194,7 +194,7 @@ extension HeroContext {
           snapshot = UIVisualEffectView(effect: effectView.effect)
           snapshot.frame = effectView.bounds
         } else {
-          snapshot = view.snapshotView()
+          snapshot = view.snapshotView() ?? UIView()
         }
       #endif
     }

diff --git a/Sources/Transition/HeroTransition.swift b/Sources/Transition/HeroTransition.swift
@@ -147,10 +147,10 @@ open class HeroTransition: NSObject {
     return inNavigationController || inTabBarController
   }
   internal var toOverFullScreen: Bool {
-    return !inContainerController && (toViewController!.modalPresentationStyle == .overFullScreen || toViewController!.modalPresentationStyle == .overCurrentContext)
+    return !inContainerController && (toViewController?.modalPresentationStyle == .overFullScreen || toViewController?.modalPresentationStyle == .overCurrentContext)
   }
   internal var fromOverFullScreen: Bool {
-    return !inContainerController && (fromViewController!.modalPresentationStyle == .overFullScreen || fromViewController!.modalPresentationStyle == .overCurrentContext)
+    return !inContainerController && (fromViewController?.modalPresentationStyle == .overFullScreen || fromViewController?.modalPresentationStyle == .overCurrentContext)
   }
 
   internal var toView: UIView? { return toViewController?.view }