Deprecate transitionController.dismisser and move the APIs into Trans…

…itionController.

Summary: Also generally consolidating transition gesture recognizers into a single entity so that it's easier to add gesture recognizers to the transition.

Reviewers: O2 Material Motion, O4 Material Apple platform reviewers, #material_motion, markwei

Reviewed By: O2 Material Motion, O4 Material Apple platform reviewers, #material_motion, markwei

Tags: #material_motion

Differential Revision: http://codereview.cc/D3068

examples/ContextualTransitionExample.swift

@@ -202,11 +202,10 @@ class PhotoAlbumViewController: UIViewController, UICollectionViewDataSource, UI
 
     view.addSubview(collectionView)
 
-    let dismisser = transitionController.dismisser
-    dismisser.disableSimultaneousRecognition(of: collectionView.panGestureRecognizer)
+    transitionController.disableSimultaneousRecognition(of: collectionView.panGestureRecognizer)
 
     for gesture in [UIPanGestureRecognizer(), UIPinchGestureRecognizer(), UIRotationGestureRecognizer()] {
-      dismisser.dismissWhenGestureRecognizerBegins(gesture)
+      transitionController.dismissWhenGestureRecognizerBegins(gesture)
       view.addGestureRecognizer(gesture)
     }
   }

examples/InteractivePushBackTransitionExample.swift

@@ -59,8 +59,8 @@ private class ModalViewController: UIViewController, UIGestureRecognizerDelegate
     view.addSubview(scrollView)
 
     let pan = UIPanGestureRecognizer()
-    pan.delegate = transitionController.dismisser.topEdgeDismisserDelegate(for: scrollView)
-    transitionController.dismisser.dismissWhenGestureRecognizerBegins(pan)
+    pan.delegate = transitionController.topEdgeDismisserDelegate(for: scrollView)
+    transitionController.dismissWhenGestureRecognizerBegins(pan)
     scrollView.panGestureRecognizer.require(toFail: pan)
     view.addGestureRecognizer(pan)
   }

src/transitions/TransitionContext.swift

@@ -85,11 +85,7 @@ public final class TransitionContext: NSObject {
   public let fore: UIViewController
 
   /** The set of gesture recognizers associated with this transition. */
-  public var gestureRecognizers: Set<UIGestureRecognizer> {
-    get {
-      return dismisser.gestureRecognizers
-    }
-  }
+  public let gestureRecognizers: Set<UIGestureRecognizer>
 
   /** The runtime to which motion should be registered. */
   fileprivate var runtime: MotionRuntime!
@@ -100,12 +96,12 @@ public final class TransitionContext: NSObject {
        direction: TransitionDirection,
        back: UIViewController,
        fore: UIViewController,
-       dismisser: ViewControllerDismisser) {
+       gestureRecognizers: Set<UIGestureRecognizer>) {
     self.direction = createProperty("Transition.direction", withInitialValue: direction)
     self.initialDirection = direction
     self.back = back
     self.fore = fore
-    self.dismisser = dismisser
+    self.gestureRecognizers = gestureRecognizers
     self.window = TransitionTimeWindow(duration: TransitionContext.defaultDuration)
 
     // TODO: Create a Timeline.
@@ -118,7 +114,6 @@ public final class TransitionContext: NSObject {
   fileprivate let initialDirection: TransitionDirection
   fileprivate var transition: Transition!
   fileprivate var context: UIViewControllerContextTransitioning!
-  fileprivate let dismisser: ViewControllerDismisser
   fileprivate var didRegisterTerminator = false
 }
 

src/transitions/TransitionController.swift

@@ -69,14 +69,44 @@ public final class TransitionController {
   }
 
   /**
-   Gesture recognizers associated with a view controller dismisser will cause the associated view
-   controller to be dismissed when the gesture recognizers begin.
+   Start a dismiss transition when the given gesture recognizer enters its began or recognized
+   state.
 
-   Provided gesture recognizers will also be made available to the Transition instance via the
-   TransitionContext's gestureRecognizers property.
+   The provided gesture recognizer will be made available to the transition instance via the
+   TransitionContext's `gestureRecognizers` property.
    */
-  public var dismisser: ViewControllerDismisser {
-    return _transitioningDelegate.dismisser
+  public func dismissWhenGestureRecognizerBegins(_ gestureRecognizer: UIGestureRecognizer) {
+    _transitioningDelegate.dismisser.dismissWhenGestureRecognizerBegins(gestureRecognizer)
+  }
+
+  /**
+   Will not allow the provided gesture recognizer to recognize simultaneously with other gesture
+   recognizers.
+
+   This method assumes that the provided gesture recognizer's delegate has been assigned to the
+   transition controller's gesture delegate.
+   */
+  public func disableSimultaneousRecognition(of gestureRecognizer: UIGestureRecognizer) {
+    _transitioningDelegate.dismisser.disableSimultaneousRecognition(of: gestureRecognizer)
+  }
+
+  /**
+   Returns a gesture recognizer delegate that will allow the gesture recognizer to begin only if the
+   provided scroll view is scrolled to the top of its content.
+
+   The returned delegate implements gestureRecognizerShouldBegin.
+   */
+  public func topEdgeDismisserDelegate(for scrollView: UIScrollView) -> UIGestureRecognizerDelegate {
+    return _transitioningDelegate.dismisser.topEdgeDismisserDelegate(for: scrollView)
+  }
+
+  /**
+   The set of gesture recognizers that will be provided to the transition via the TransitionContext
+   instance.
+   */
+  public var gestureRecognizers: Set<UIGestureRecognizer> {
+    set { _transitioningDelegate.gestureDelegate.gestureRecognizers = newValue }
+    get { return _transitioningDelegate.gestureDelegate.gestureRecognizers }
   }
 
   /**
@@ -89,18 +119,33 @@ public final class TransitionController {
     return _transitioningDelegate
   }
 
+  /**
+   The gesture recognizer delegate managed by this controller.
+   */
+  public var gestureDelegate: UIGestureRecognizerDelegate {
+    return _transitioningDelegate.gestureDelegate
+  }
+
   init(viewController: UIViewController) {
     _transitioningDelegate = TransitioningDelegate(viewController: viewController)
   }
 
+  /**
+   Deprecated. Please use methods directly on the transitionController instead.
+   */
+  @available(*, deprecated, message: "Please use methods directly on the transitionController instead.")
+  public var dismisser: ViewControllerDismisser {
+    return _transitioningDelegate.dismisser
+  }
+
   fileprivate let _transitioningDelegate: TransitioningDelegate
 }
 
 private final class TransitioningDelegate: NSObject, UIViewControllerTransitioningDelegate {
   init(viewController: UIViewController) {
     self.associatedViewController = viewController
 
-    self.dismisser = ViewControllerDismisser()
+    self.dismisser = ViewControllerDismisser(gestureDelegate: self.gestureDelegate)
 
     super.init()
 
@@ -109,7 +154,9 @@ private final class TransitioningDelegate: NSObject, UIViewControllerTransitioni
 
   var ctx: TransitionContext?
   var transitionType: Transition.Type?
+
   let dismisser: ViewControllerDismisser
+  let gestureDelegate = GestureDelegate()
 
   weak var associatedViewController: UIViewController?
 
@@ -133,7 +180,7 @@ private final class TransitioningDelegate: NSObject, UIViewControllerTransitioni
                               direction: direction,
                               back: back,
                               fore: fore,
-                              dismisser: dismisser)
+                              gestureRecognizers: gestureDelegate.gestureRecognizers)
       ctx?.delegate = self
     }
   }

src/transitions/ViewControllerDismisser.swift

@@ -74,10 +74,15 @@ public final class ViewControllerDismisser {
   weak var delegate: ViewControllerDismisserDelegate?
 
   public var gestureRecognizers: Set<UIGestureRecognizer> {
-    return gestureDelegate.gestureRecognizers
+    set { gestureDelegate.gestureRecognizers = newValue }
+    get { return gestureDelegate.gestureRecognizers }
   }
 
-  private var gestureDelegate = GestureDelegate()
+  init(gestureDelegate: GestureDelegate) {
+    self.gestureDelegate = gestureDelegate
+  }
+
+  private var gestureDelegate: GestureDelegate
   private var scrollViewTopEdgeDismisserDelegates: [ScrollViewTopEdgeDismisserDelegate] = []
 }
 
@@ -93,9 +98,9 @@ private final class ScrollViewTopEdgeDismisserDelegate: NSObject, UIGestureRecog
   weak var scrollView: UIScrollView?
 }
 
-private final class GestureDelegate: NSObject, UIGestureRecognizerDelegate {
-  fileprivate var gestureRecognizers = Set<UIGestureRecognizer>()
-  fileprivate var soloGestureRecognizers = Set<UIGestureRecognizer>()
+final class GestureDelegate: NSObject, UIGestureRecognizerDelegate {
+  var gestureRecognizers = Set<UIGestureRecognizer>()
+  var soloGestureRecognizers = Set<UIGestureRecognizer>()
 
   public func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldRecognizeSimultaneouslyWith otherGestureRecognizer: UIGestureRecognizer) -> Bool {
     if soloGestureRecognizers.contains(gestureRecognizer) || soloGestureRecognizers.contains(otherGestureRecognizer) {