Allow to choose dragging and paging animations #minor

Documentation/Usage.md

@@ -227,7 +227,7 @@ Transform your `Pager` into an endless sroll by using `loopPages`:
 
 ## Page Transitions
 
-Use `draggingAnimation(_:)`  to customize the _transition_ to the next page.
+Use `draggingAnimation(onChange:, onEnded:)`  to customize the animations applied while dragging items and/or transitioning to the next element.
 
 ```swift
 Pager(...)

Sources/SwiftUIPager/PageConfiguration/PagingAnimation.swift

@@ -33,7 +33,7 @@ public enum PagingAnimation: Equatable {
     /// Pass your custom animation
     ///
     /// - Parameter animation: animation to be applied
-    case custom(animation: Animation)
+    case custom(animation: Animation?)
 
     /// Standard animation. Single pagination `Pager` defaults to this value. Ease-out, 0.35 seconds.
     public static var standard: PagingAnimation = .standard(duration: 0.35)
@@ -42,15 +42,18 @@ public enum PagingAnimation: Equatable {
     /// See the bezier curve [here](https://cubic-bezier.com/#.2,1,.9,1).
     public static var steep: PagingAnimation = .steep(duration: 0.2)
 
+    /// No animation applied
+    public static var none: PagingAnimation = .custom(animation: nil)
+
     /// Translates the option selected to a `SwiftUI` animation
-    var animation: Animation {
+    var animation: Animation? {
         switch self {
         case .steep(let duration):
             return Animation.timingCurve(0.2, 1, 0.9, 1, duration: duration)
         case .standard(let duration):
             return Animation.easeOut(duration: duration)
         case .interactive:
-            return .interactiveSpring(response: 0.3, dampingFraction: 0.8, blendDuration: 0.5)
+            return .interactiveSpring()
         case .custom(let animation):
             return animation
         }

Sources/SwiftUIPager/Pager+Buildable.swift

@@ -70,13 +70,27 @@ extension Pager: Buildable {
 
     #if !os(tvOS)
 
-    /// Sets the explicit animation used for dragging
+    /// Sets the explicit animation to be used. Defaults to `.standard`
     ///
-    /// - Parameter value: explicit animation
-    public func draggingAnimation(_ value: DraggingAnimation?) -> Self {
+    /// - Parameter value: animation to use while dragging and to page
+    ///
+    /// - Warning: `spring` animations don't work well. Avoid high responses while dragging as the animation should be short
+    public func draggingAnimation(_ value: DraggingAnimation) -> Self {
         mutating(keyPath: \.draggingAnimation, value: value)
     }
 
+    /// Sets the explicit animation to be used. Defaults to `.standard`
+    ///
+    /// - Parameter anim1: animation to use while dragging
+    /// - Parameter anim2: animation to use to page
+    ///
+    /// - Note: Setting different animations could cause unexpected behavior
+    /// - Warning: `spring` animations don't work well. Avoid high responses while dragging as the animation should be short
+    public func draggingAnimation(onChange anim1: DraggingAnimation, onEnded anim2: DraggingAnimation) -> Self {
+        mutating(keyPath: \.draggingAnimation, value: anim1)
+            .mutating(keyPath: \.pagingAnimation, value: { _ in anim2 })
+    }
+
     /// Sensitivity used to determine whether or not to swipe the page
     ///
     /// - Parameter value: sensitivity to be applied when paginating

Sources/SwiftUIPager/Pager.swift

@@ -73,7 +73,7 @@ public struct Pager<Element, ID, PageView>: View  where PageView: View, Element:
     var pagingAnimation: ((DragResult) -> PagingAnimation)?
 
     /// Animation used for dragging
-    var draggingAnimation: DraggingAnimation?
+    var draggingAnimation: DraggingAnimation = .standard
 
     /// Sensitivity used to determine whether or not to swipe the page
     var sensitivity: PaginationSensitivity = .default

Sources/SwiftUIPager/PagerContent+Buildable.swift

@@ -70,13 +70,27 @@ extension Pager.PagerContent: Buildable {
 
     #if !os(tvOS)
 
-    /// Sets the explicit animation used for dragging
+    /// Sets the explicit animation to be used. Defaults to `.standard`
     ///
-    /// - Parameter value: explicit animation
-    func draggingAnimation(_ value: DraggingAnimation?) -> Self {
+    /// - Parameter value: animation to use while dragging and to page
+    /// 
+    /// - Warning: `spring` animations don't work well. Avoid high responses while dragging as the animation should be short
+    func draggingAnimation(_ value: DraggingAnimation) -> Self {
         mutating(keyPath: \.draggingAnimation, value: value)
     }
 
+    /// Sets the explicit animation to be used. Defaults to `.standard`
+    ///
+    /// - Parameter anim1: animation to use while dragging
+    /// - Parameter anim2: animation to use to page
+    ///
+    /// - Note: Setting different animations could cause unexpected behavior
+    /// - Warning: `spring` animations don't work well. Avoid high responses while dragging as the animation should be short
+    func draggingAnimation(onChange anim1: DraggingAnimation, onEnded anim2: DraggingAnimation) -> Self {
+        mutating(keyPath: \.draggingAnimation, value: anim1)
+            .mutating(keyPath: \.pagingAnimation, value: { _ in anim2 })
+    }
+
     /// Sensitivity used to determine whether or not to swipe the page
     ///
     /// - Parameter value: sensitivity to be applied when paginating

Sources/SwiftUIPager/PagerContent.swift

@@ -57,7 +57,7 @@ extension Pager {
         var pagingAnimation: ((DragResult) -> PagingAnimation)?
 
         /// Animation used for dragging
-        var draggingAnimation: DraggingAnimation?
+        var draggingAnimation: DraggingAnimation = .standard
 
         /// Sensitivity used to determine whether or not to swipe the page
         var sensitivity: PaginationSensitivity = .default
@@ -225,7 +225,7 @@ extension Pager.PagerContent {
     }
 
     func onDragChanged(with value: DragGesture.Value) {
-        let animation = draggingAnimation?.animation ?? .default
+        let animation = draggingAnimation.animation
         withAnimation(animation) {
             if self.lastDraggingValue == nil {
                 onDraggingBegan?()
@@ -280,9 +280,9 @@ extension Pager.PagerContent {
             speed = 1 / min(4, Double(pageIncrement))
         }
 
-        let pagingAnimation = self.draggingAnimation ?? self.pagingAnimation?((page, newPage, draggingOffset, draggingVelocity)) ?? defaultPagingAnimation
+        let pagingAnimation = self.pagingAnimation?((page, newPage, draggingOffset, draggingVelocity)) ?? defaultPagingAnimation
 
-        let animation = pagingAnimation.animation.speed(speed)
+        let animation = pagingAnimation.animation?.speed(speed)
         if page != newPage {
             onPageWillChange?(newPage)
         }

Tests/SwiftUIPagerTests/Pager+Buildable_Tests.swift

@@ -35,7 +35,7 @@ final class Pager_Buildable_Tests: XCTestCase {
         XCTAssertEqual(pager.contentLoadingPolicy, .default)
         XCTAssertEqual(pager.allowsMultiplePagination, false)
         XCTAssertNil(pager.pagingAnimation)
-        XCTAssertNil(pager.draggingAnimation)
+        XCTAssertEqual(pager.draggingAnimation, PagingAnimation.standard)
         XCTAssertEqual(pager.sensitivity, .default)
         XCTAssertEqual(pager.pageRatio, 1)
         XCTAssertTrue(pager.bounces)
@@ -122,6 +122,16 @@ final class Pager_Buildable_Tests: XCTestCase {
         XCTAssertEqual(animation, PagingAnimation.steep)
     }
 
+    func test_GivenPager_WhenDraggingAnimation_ThenDraggingAndPagingAnimationNotNil() throws {
+        var pager = givenPager
+        pager = pager.draggingAnimation(onChange: .interactive, onEnded: .steep)
+        let pagerContent = pager.content(for: CGSize(width: 100, height: 100))
+        let anim1 = try XCTUnwrap(pagerContent.draggingAnimation)
+        let anim2 = try XCTUnwrap(pagerContent.pagingAnimation?((0, 0, 0, 0)))
+        XCTAssertEqual(anim1, PagingAnimation.interactive)
+        XCTAssertEqual(anim2, PagingAnimation.steep)
+    }
+
     func test_GivenPager_WhenMultiplePagination_ThenAllowsMultiplePagination() {
         var pager = givenPager
         pager = pager.multiplePagination()
@@ -617,6 +627,7 @@ final class Pager_Buildable_Tests: XCTestCase {
         ("test_GivenPagerWith3DRotation_WhenInteractive_ThenInteractiveScaleNotChanged", test_GivenPagerWith3DRotation_WhenInteractive_ThenInteractiveScaleNotChanged),
         ("test_GivenPager_When3DRotation_ThenShouldRotate", test_GivenPager_When3DRotation_ThenShouldRotate),
         ("test_GivenPagerWith3DRotation_When3DRotationFalse_ThenShouldRotateFalse", test_GivenPagerWith3DRotation_When3DRotationFalse_ThenShouldRotateFalse),
+        ("test_GivenPager_WhenDraggingAnimation_ThenDraggingAndPagingAnimationNotNil", test_GivenPager_WhenDraggingAnimation_ThenDraggingAndPagingAnimationNotNil),
         ("test_GivenPager_WhenDraggingAnimation_ThenDraggingAnimationNotNil", test_GivenPager_WhenDraggingAnimation_ThenDraggingAnimationNotNil),
         ("test_GivenPager_WhenHorizontalRightToLeft_ThenScrollAngle", test_GivenPager_WhenHorizontalRightToLeft_ThenScrollAngle),
         ("test_GivenPager_WhenAlignment_ThenAlignmentSet", test_GivenPager_WhenAlignment_ThenAlignmentSet),

Tests/SwiftUIPagerTests/PagingAnimation_Tests.swift

@@ -31,12 +31,17 @@ final class PagingAnimation_Tests: XCTestCase {
     }
 
     func test_GivenPagingAnimationInteractive_WhenAnimation_ThenExpectedAnimationValues() {
-        let input = Animation.interactiveSpring(response: 0.3, dampingFraction: 0.8, blendDuration: 0.5)
+        let input = Animation.interactiveSpring()
         let pagingAnimation: PagingAnimation = .interactive
         let animation = pagingAnimation.animation
         XCTAssertEqual(animation, input)
     }
 
+    func test_GivenPagingAnimationNone_WhenAnimation_ThenNil() {
+        let pagingAnimation: PagingAnimation = .none
+        XCTAssertNil(pagingAnimation.animation)
+    }
+
     static var allTests = [
         ("test_GivenPagingAnimationSteep_WhenAnimation_ThenExpectedAnimationValues", test_GivenPagingAnimationSteep_WhenAnimation_ThenExpectedAnimationValues),
         ("test_GivenPagingAnimationStandard_WhenAnimation_ThenExpectedAnimationValues", test_GivenPagingAnimationStandard_WhenAnimation_ThenExpectedAnimationValues),

release_description.md

@@ -1,14 +1,6 @@
 ### Features
-- New `interactive(opacity:)` to add an interactive fade in/out effect to the scroll
-- New `interactive(scale:)` and `interactive(rotation:)`
-- Interactive effects can be now combined
-- CI/CD to build `legacy-projects` branch against _iOS 12_
-
-### Fixes
-- Items not scrolling in _iOS 13_ 
-- #193 Transitions are jumpy if fast
-- #194 `AnimatableModifier` symbol not found
+- New `dragggingAnimation(_:)` modifier to select an animation to use while dragging
+- Convenience builder methods `none` and `interactiveSpring` to create `DraggingAnimation`
 
 ### Deprecations
-- `rotation3D()` in favor of `interactive(rotation:)`
-- `interactive(_:)` in favor of `interactive(scale:)`
+- `pagingAnimation(_:)` in favor of `dragggingAnimation(_:)`