Merge pull request #72 from fermoya/fix/issue-69

Fix/issue 69 Gesture state not resetting if canceled

Example/SwiftUIPagerExample.xcodeproj/project.pbxproj

@@ -17,6 +17,7 @@
 		6B4EC8A4240D07D5001E7490 /* InfiniteExampleView.swift in Sources */ = {isa = PBXBuildFile; fileRef = 6B4EC8A3240D07D5001E7490 /* InfiniteExampleView.swift */; };
 		6B4EC8A6240D0918001E7490 /* EmbeddedExampleView.swift in Sources */ = {isa = PBXBuildFile; fileRef = 6B4EC8A5240D0918001E7490 /* EmbeddedExampleView.swift */; };
 		6B4EC8A8240D1182001E7490 /* BizarreExampleView.swift in Sources */ = {isa = PBXBuildFile; fileRef = 6B4EC8A7240D1182001E7490 /* BizarreExampleView.swift */; };
+		6B9C4A8A24B45F66004C06C5 /* OnDeactivateModifier.swift in Sources */ = {isa = PBXBuildFile; fileRef = 6B9C4A8924B45F66004C06C5 /* OnDeactivateModifier.swift */; };
 		6BC5EDFC24866D9500E1E78C /* Pager+Buildable.swift in Sources */ = {isa = PBXBuildFile; fileRef = 6BC5EDF424866D9500E1E78C /* Pager+Buildable.swift */; };
 		6BC5EDFE24866D9500E1E78C /* View+Helper.swift in Sources */ = {isa = PBXBuildFile; fileRef = 6BC5EDF724866D9500E1E78C /* View+Helper.swift */; };
 		6BC5EDFF24866D9500E1E78C /* Buildable.swift in Sources */ = {isa = PBXBuildFile; fileRef = 6BC5EDF824866D9500E1E78C /* Buildable.swift */; };
@@ -57,6 +58,7 @@
 		6B4EC8A3240D07D5001E7490 /* InfiniteExampleView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = InfiniteExampleView.swift; sourceTree = "<group>"; };
 		6B4EC8A5240D0918001E7490 /* EmbeddedExampleView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = EmbeddedExampleView.swift; sourceTree = "<group>"; };
 		6B4EC8A7240D1182001E7490 /* BizarreExampleView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = BizarreExampleView.swift; sourceTree = "<group>"; };
+		6B9C4A8924B45F66004C06C5 /* OnDeactivateModifier.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = OnDeactivateModifier.swift; sourceTree = "<group>"; };
 		6BC5EDF424866D9500E1E78C /* Pager+Buildable.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; name = "Pager+Buildable.swift"; path = "../../Sources/SwiftUIPager/Pager+Buildable.swift"; sourceTree = "<group>"; };
 		6BC5EDF724866D9500E1E78C /* View+Helper.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = "View+Helper.swift"; sourceTree = "<group>"; };
 		6BC5EDF824866D9500E1E78C /* Buildable.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = Buildable.swift; sourceTree = "<group>"; };
@@ -149,6 +151,7 @@
 			isa = PBXGroup;
 			children = (
 				6BC5EDF824866D9500E1E78C /* Buildable.swift */,
+				6B9C4A8924B45F66004C06C5 /* OnDeactivateModifier.swift */,
 				6BC5EDF924866D9500E1E78C /* SizeViewModifier.swift */,
 				6BC5EDF724866D9500E1E78C /* View+Helper.swift */,
 			);
@@ -250,6 +253,7 @@
 				6B4EC8A8240D1182001E7490 /* BizarreExampleView.swift in Sources */,
 				17D9E0F623D4CF6700C5AE93 /* SceneDelegate.swift in Sources */,
 				6BC5EDFF24866D9500E1E78C /* Buildable.swift in Sources */,
+				6B9C4A8A24B45F66004C06C5 /* OnDeactivateModifier.swift in Sources */,
 				6BEA731624ACF8D7007EA8DC /* GesturePriority.swift in Sources */,
 				6BEA731324ACF8D7007EA8DC /* PositionAlignment.swift in Sources */,
 				6BEA731424ACF8D7007EA8DC /* SwipeDirection.swift in Sources */,
@@ -402,6 +406,7 @@
 				DEVELOPMENT_TEAM = LPBB5C5CRP;
 				ENABLE_PREVIEWS = YES;
 				INFOPLIST_FILE = SwiftUIPagerExample/Info.plist;
+				IPHONEOS_DEPLOYMENT_TARGET = 13.0;
 				LD_RUNPATH_SEARCH_PATHS = (
 					"$(inherited)",
 					"@executable_path/Frameworks",
@@ -422,6 +427,7 @@
 				DEVELOPMENT_TEAM = LPBB5C5CRP;
 				ENABLE_PREVIEWS = YES;
 				INFOPLIST_FILE = SwiftUIPagerExample/Info.plist;
+				IPHONEOS_DEPLOYMENT_TARGET = 13.0;
 				LD_RUNPATH_SEARCH_PATHS = (
 					"$(inherited)",
 					"@executable_path/Frameworks",

Sources/SwiftUIPager/Helpers/OnDeactivateModifier.swift

@@ -0,0 +1,37 @@
+//
+//  OnDeactivateModifier.swift
+//  SwiftUIPagerExample
+//
+//  Created by Fernando Moya de Rivas on 07/07/2020.
+//  Copyright © 2020 Fernando Moya de Rivas. All rights reserved.
+//
+
+import SwiftUI
+
+@available(iOS 13.0, OSX 10.15, tvOS 13.0, watchOS 6.0, *)
+struct OnDeactivateView<Content: View>: View {
+
+    var content: Content
+    var perform: () -> Void
+
+    var body: some View {
+        #if os(iOS)
+        return content
+            .onReceive(NotificationCenter.default.publisher(for: UIScene.didActivateNotification), perform: { _ in
+                self.perform()
+            })
+        #else
+        return content
+        #endif
+    }
+
+}
+
+@available(iOS 13.0, OSX 10.15, tvOS 13.0, watchOS 6.0, *)
+extension View {
+
+    func onDeactivate(perform: @escaping () -> Void) -> some View {
+        return OnDeactivateView(content: self, perform: perform)
+    }
+
+}

Sources/SwiftUIPager/Pager.swift

@@ -123,11 +123,14 @@ public struct Pager<Element, ID, PageView>: View  where PageView: View, Element:
     /// Size of the view
     @State var size: CGSize = .zero
 
-    /// Translation on the X-Axis
+    /// `swipeGesture` translation on the X-Axis
     @State var draggingOffset: CGFloat = 0
 
-    /// The moment when the dragging gesture started
-    @State var draggingStartTime: Date! = nil
+    /// `swipeGesture` velocity on the X-Axis
+    @State var draggingVelocity: Double = 0
+
+    /// Timestamp of the last `swipeGesture` entry
+    @State var draggingTimestamp: Date!
 
     /// Page index
     @Binding var pageIndex: Int {
@@ -179,6 +182,13 @@ public struct Pager<Element, ID, PageView>: View  where PageView: View, Element:
             .onAppear(perform: {
                 self.onPageChanged?(self.page)
             })
+            .onDeactivate(perform: {
+                if self.isDragging {
+                    #if !os(tvOS)
+                    self.onDragGestureEnded()
+                    #endif
+                }
+            })
     }
 
 }
@@ -210,25 +220,43 @@ extension Pager {
         DragGesture(minimumDistance: minimumDistance)
             .onChanged({ value in
                 withAnimation {
-                    self.draggingStartTime = self.draggingStartTime ?? value.time
                     let side = self.isHorizontal ? self.size.width : self.size.height
-                    self.draggingOffset = value.translation.width * (self.pageDistance / side)
-                }
-            }).onEnded({ (value) in
-                let velocity = -Double(self.draggingOffset) / value.time.timeIntervalSince(self.draggingStartTime ?? Date())
-                var newPage = self.currentPage
-                if newPage == self.page, abs(velocity) > 1000 {
-                    newPage = newPage + Int(velocity / abs(velocity))
-                }
+                    let newOffset = value.translation.width * (self.pageDistance / side)
 
-                newPage = max(0, min(self.numberOfPages - 1, newPage))
+                    let timeIncrement = value.time.timeIntervalSince(self.draggingTimestamp ?? value.time)
+                    let offsetIncrement = (newOffset - self.draggingOffset) * (side / self.pageDistance)
+                    if timeIncrement != 0 {
+                        self.draggingVelocity = Double(offsetIncrement) / timeIncrement
+                    }
 
-                withAnimation(.easeOut) {
-                    self.draggingOffset = 0
-                    self.pageIndex = newPage
-                    self.draggingStartTime = nil
+                    self.draggingTimestamp = value.time
+                    self.draggingOffset = newOffset
                 }
             })
+            .onEnded({ (value) in
+                self.onDragGestureEnded()
+            })
+    }
+
+    private func onDragGestureEnded() {
+        let velocity = -self.draggingVelocity
+        var newPage = self.currentPage
+        if newPage == self.page, abs(velocity) > 500 {
+            if isInifinitePager {
+                newPage = (newPage + Int(velocity / abs(velocity)) + self.numberOfPages) % self.numberOfPages
+            } else {
+                newPage = newPage + Int(velocity / abs(velocity))
+            }
+        }
+
+        newPage = max(0, min(self.numberOfPages - 1, newPage))
+
+        withAnimation(.easeOut) {
+            self.draggingOffset = 0
+            self.pageIndex = newPage
+            self.draggingVelocity = 0
+            self.draggingTimestamp = nil
+        }
     }
     #endif
 

SwiftUIPager.podspec

@@ -1,7 +1,7 @@
 Pod::Spec.new do |s|
 
   s.name         = "SwiftUIPager"
-  s.version      = "1.8.0-beta.1"
+  s.version      = "1.8.0"
   s.summary      = "Native pager for SwiftUI. Easily to use, easy to customize."
 
   s.description  = <<-DESC

SwiftUIPager.xcframework/Info.plist

@@ -6,106 +6,106 @@
 	<array>
 		<dict>
 			<key>LibraryIdentifier</key>
-			<string>ios-x86_64-maccatalyst</string>
+			<string>ios-arm64</string>
 			<key>LibraryPath</key>
 			<string>SwiftUIPager.framework</string>
 			<key>SupportedArchitectures</key>
 			<array>
-				<string>x86_64</string>
+				<string>arm64</string>
 			</array>
 			<key>SupportedPlatform</key>
 			<string>ios</string>
-			<key>SupportedPlatformVariant</key>
-			<string>maccatalyst</string>
 		</dict>
 		<dict>
 			<key>LibraryIdentifier</key>
-			<string>macos-x86_64</string>
+			<string>tvos-arm64</string>
 			<key>LibraryPath</key>
 			<string>SwiftUIPager.framework</string>
 			<key>SupportedArchitectures</key>
 			<array>
-				<string>x86_64</string>
+				<string>arm64</string>
 			</array>
 			<key>SupportedPlatform</key>
-			<string>macos</string>
+			<string>tvos</string>
 		</dict>
 		<dict>
 			<key>LibraryIdentifier</key>
-			<string>tvos-arm64</string>
+			<string>ios-x86_64-simulator</string>
 			<key>LibraryPath</key>
 			<string>SwiftUIPager.framework</string>
 			<key>SupportedArchitectures</key>
 			<array>
-				<string>arm64</string>
+				<string>x86_64</string>
 			</array>
 			<key>SupportedPlatform</key>
-			<string>tvos</string>
+			<string>ios</string>
+			<key>SupportedPlatformVariant</key>
+			<string>simulator</string>
 		</dict>
 		<dict>
 			<key>LibraryIdentifier</key>
-			<string>tvos-x86_64-simulator</string>
+			<string>watchos-armv7k_arm64_32</string>
 			<key>LibraryPath</key>
 			<string>SwiftUIPager.framework</string>
 			<key>SupportedArchitectures</key>
 			<array>
-				<string>x86_64</string>
+				<string>armv7k</string>
+				<string>arm64_32</string>
 			</array>
 			<key>SupportedPlatform</key>
-			<string>tvos</string>
-			<key>SupportedPlatformVariant</key>
-			<string>simulator</string>
+			<string>watchos</string>
 		</dict>
 		<dict>
 			<key>LibraryIdentifier</key>
-			<string>ios-arm64</string>
+			<string>ios-x86_64-maccatalyst</string>
 			<key>LibraryPath</key>
 			<string>SwiftUIPager.framework</string>
 			<key>SupportedArchitectures</key>
 			<array>
-				<string>arm64</string>
+				<string>x86_64</string>
 			</array>
 			<key>SupportedPlatform</key>
 			<string>ios</string>
+			<key>SupportedPlatformVariant</key>
+			<string>maccatalyst</string>
 		</dict>
 		<dict>
 			<key>LibraryIdentifier</key>
-			<string>watchos-i386-simulator</string>
+			<string>macos-x86_64</string>
 			<key>LibraryPath</key>
 			<string>SwiftUIPager.framework</string>
 			<key>SupportedArchitectures</key>
 			<array>
-				<string>i386</string>
+				<string>x86_64</string>
 			</array>
 			<key>SupportedPlatform</key>
-			<string>watchos</string>
-			<key>SupportedPlatformVariant</key>
-			<string>simulator</string>
+			<string>macos</string>
 		</dict>
 		<dict>
 			<key>LibraryIdentifier</key>
-			<string>watchos-armv7k_arm64_32</string>
+			<string>tvos-x86_64-simulator</string>
 			<key>LibraryPath</key>
 			<string>SwiftUIPager.framework</string>
 			<key>SupportedArchitectures</key>
 			<array>
-				<string>armv7k</string>
-				<string>arm64_32</string>
+				<string>x86_64</string>
 			</array>
 			<key>SupportedPlatform</key>
-			<string>watchos</string>
+			<string>tvos</string>
+			<key>SupportedPlatformVariant</key>
+			<string>simulator</string>
 		</dict>
 		<dict>
 			<key>LibraryIdentifier</key>
-			<string>ios-x86_64-simulator</string>
+			<string>watchos-i386-simulator</string>
 			<key>LibraryPath</key>
 			<string>SwiftUIPager.framework</string>
 			<key>SupportedArchitectures</key>
 			<array>
-				<string>x86_64</string>
+				<string>i386</string>
 			</array>
 			<key>SupportedPlatform</key>
-			<string>ios</string>
+			<string>watchos</string>
 			<key>SupportedPlatformVariant</key>
 			<string>simulator</string>
 		</dict>

SwiftUIPager.xcframework/ios-arm64/SwiftUIPager.framework/Modules/SwiftUIPager.swiftmodule/arm64-apple-ios.swiftinterface

@@ -10,7 +10,7 @@ import SwiftUI
 public enum GesturePriority {
   case high
   case simultaneous
-  case `default`
+  case normal
   public static func == (a: SwiftUIPager.GesturePriority, b: SwiftUIPager.GesturePriority) -> Swift.Bool
   public var hashValue: Swift.Int {
     get
@@ -29,6 +29,7 @@ public enum SwipeInteractionArea {
 }
 @available(iOS 13.0, OSX 10.15, tvOS 13.0, watchOS 6.0, *)
 extension Pager {
+  public func contentLoadingPolicy(_ value: SwiftUIPager.ContentLoadingPolicy) -> SwiftUIPager.Pager<Element, ID, PageView>
   public func loopPages(_ value: Swift.Bool = true) -> SwiftUIPager.Pager<Element, ID, PageView>
   public func disableDragging() -> SwiftUIPager.Pager<Element, ID, PageView>
   public func allowsDragging(_ value: Swift.Bool = true) -> SwiftUIPager.Pager<Element, ID, PageView>
@@ -49,6 +50,11 @@ extension Pager {
   public func padding(_ insets: SwiftUI.EdgeInsets) -> SwiftUIPager.Pager<Element, ID, PageView>
   public func padding(_ edges: SwiftUI.Edge.Set = .all, _ length: CoreGraphics.CGFloat? = nil) -> SwiftUIPager.Pager<Element, ID, PageView>
 }
+public enum ContentLoadingPolicy : Swift.Equatable {
+  case lazy(recyclingRatio: Swift.UInt)
+  case eager
+  public static func == (a: SwiftUIPager.ContentLoadingPolicy, b: SwiftUIPager.ContentLoadingPolicy) -> Swift.Bool
+}
 @available(iOS 13.0, OSX 10.15, tvOS 13.0, watchOS 6.0, *)
 public struct Pager<Element, ID, PageView> : SwiftUI.View where Element : Swift.Equatable, ID : Swift.Hashable, PageView : SwiftUI.View {
   public init(page: SwiftUI.Binding<Swift.Int>, data: [Element], id: Swift.KeyPath<Element, ID>, @SwiftUI.ViewBuilder content: @escaping (Element) -> PageView)

SwiftUIPager.xcframework/ios-arm64/SwiftUIPager.framework/Modules/SwiftUIPager.swiftmodule/arm64.swiftinterface

@@ -10,7 +10,7 @@ import SwiftUI
 public enum GesturePriority {
   case high
   case simultaneous
-  case `default`
+  case normal
   public static func == (a: SwiftUIPager.GesturePriority, b: SwiftUIPager.GesturePriority) -> Swift.Bool
   public var hashValue: Swift.Int {
     get
@@ -29,6 +29,7 @@ public enum SwipeInteractionArea {
 }
 @available(iOS 13.0, OSX 10.15, tvOS 13.0, watchOS 6.0, *)
 extension Pager {
+  public func contentLoadingPolicy(_ value: SwiftUIPager.ContentLoadingPolicy) -> SwiftUIPager.Pager<Element, ID, PageView>
   public func loopPages(_ value: Swift.Bool = true) -> SwiftUIPager.Pager<Element, ID, PageView>
   public func disableDragging() -> SwiftUIPager.Pager<Element, ID, PageView>
   public func allowsDragging(_ value: Swift.Bool = true) -> SwiftUIPager.Pager<Element, ID, PageView>
@@ -49,6 +50,11 @@ extension Pager {
   public func padding(_ insets: SwiftUI.EdgeInsets) -> SwiftUIPager.Pager<Element, ID, PageView>
   public func padding(_ edges: SwiftUI.Edge.Set = .all, _ length: CoreGraphics.CGFloat? = nil) -> SwiftUIPager.Pager<Element, ID, PageView>
 }
+public enum ContentLoadingPolicy : Swift.Equatable {
+  case lazy(recyclingRatio: Swift.UInt)
+  case eager
+  public static func == (a: SwiftUIPager.ContentLoadingPolicy, b: SwiftUIPager.ContentLoadingPolicy) -> Swift.Bool
+}
 @available(iOS 13.0, OSX 10.15, tvOS 13.0, watchOS 6.0, *)
 public struct Pager<Element, ID, PageView> : SwiftUI.View where Element : Swift.Equatable, ID : Swift.Hashable, PageView : SwiftUI.View {
   public init(page: SwiftUI.Binding<Swift.Int>, data: [Element], id: Swift.KeyPath<Element, ID>, @SwiftUI.ViewBuilder content: @escaping (Element) -> PageView)