Merge commit '7621e2f8dec938cf48181c8b10afc9b01f444e68' into beta

submodules/DirectionalPanGesture/BUILD

@@ -0,0 +1,15 @@
+load("@build_bazel_rules_swift//swift:swift.bzl", "swift_library")
+
+swift_library(
+    name = "DirectionalPanGesture",
+    module_name = "DirectionalPanGesture",
+    srcs = glob([
+        "Sources/**/*.swift",
+    ]),
+    copts = [
+        "-warnings-as-errors",
+    ],
+    visibility = [
+        "//visibility:public",
+    ],
+)

submodules/DirectionalPanGesture/Sources/DirectionalPanGestureRecognizer.swift

@@ -0,0 +1,77 @@
+import Foundation
+import UIKit
+
+open class DirectionalPanGestureRecognizer: UIPanGestureRecognizer {
+    public enum Direction {
+        case horizontal
+        case vertical
+    }
+    
+    private var validatedGesture = false
+    private var firstLocation: CGPoint = CGPoint()
+    
+    public var shouldBegin: ((CGPoint) -> Bool)?
+    
+    public var direction: Direction = .vertical
+    
+    override public init(target: Any?, action: Selector?) {
+        super.init(target: target, action: action)
+        
+        self.maximumNumberOfTouches = 1
+    }
+    
+    override public func reset() {
+        super.reset()
+        
+        self.validatedGesture = false
+    }
+    
+    override public func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent) {
+        super.touchesBegan(touches, with: event)
+        
+        let touch = touches.first!
+        let point = touch.location(in: self.view)
+        if let shouldBegin = self.shouldBegin, !shouldBegin(point) {
+            self.state = .failed
+            return
+        }
+        
+        self.firstLocation = point
+        
+        if let target = self.view?.hitTest(self.firstLocation, with: event) {
+            if target == self.view {
+                self.validatedGesture = true
+            }
+        }
+    }
+    
+    override public func touchesMoved(_ touches: Set<UITouch>, with event: UIEvent) {
+        let location = touches.first!.location(in: self.view)
+        let translation = CGPoint(x: location.x - self.firstLocation.x, y: location.y - self.firstLocation.y)
+        
+        let absTranslationX: CGFloat = abs(translation.x)
+        let absTranslationY: CGFloat = abs(translation.y)
+        
+        if !self.validatedGesture {
+            switch self.direction {
+                case .horizontal:
+                    if absTranslationY > 4.0 && absTranslationY > absTranslationX * 2.0 {
+                        self.state = .failed
+                    } else if absTranslationX > 2.0 && absTranslationY * 2.0 < absTranslationX {
+                        self.validatedGesture = true
+                    }
+                case .vertical:
+                    if absTranslationX > 4.0 && absTranslationX > absTranslationY * 2.0 {
+                        self.state = .failed
+                    } else if absTranslationY > 2.0 && absTranslationX * 2.0 < absTranslationY {
+                        self.validatedGesture = true
+                    }
+            }
+        }
+        
+        if self.validatedGesture {
+            super.touchesMoved(touches, with: event)
+        }
+    }
+}
+