[Issue-26] Customize animations (#28)

* [Issue-26] Customize animations

* Remove source code from README

Package.swift

@@ -21,7 +21,7 @@ let package = Package(
         ),
         .package(
             url: "https://github.com/yml-org/YMatterType.git",
-            from: "1.6.0"
+            from: "1.7.0"
         )
     ],
     targets: [

README.md

@@ -21,19 +21,6 @@ Usage
 ### Initializers
 The Bottom sheet controller can be initialized with either a title and a view or else with a view controller. 
 
-```swift
-init(
-    title: String,
-    childView: UIView,
-    appearance: BottomSheetController.Appearance = .default
-)
-
-init(
-    childController: UIViewController,
-    appearance: BottomSheetController.Appearance = .default
-)
-```
-
 When initializing with a view controller, the title is drawn from `UIViewController.title`. When the view controller is a `UINavigationController`, the header appearance options are ignored and the navigation controller's navigation bar is displayed as the sheet's header. In this situation, if you wish to have a close button, then that should be set using the view controller's `navigationItem.rightBarButtonItem` or `.leftBarButtonItem`.
 
 Both initializers include an appearance parameter that allows you to fully customize the sheet's appearance. You can also update the sheet's appearance at any time.
@@ -84,33 +71,15 @@ final class ViewController: UIViewController {
 ### Customization
 `BottomSheetController` has an `appearance` property of type `Appearance`.
 
-`Appearance` lets you customize the bottom sheet appearance. We can customize the appearance of the indicator view, the header view, dimmer color, animation etc.
+`Appearance` lets you customize how the bottom sheet both appears and behaves. You can customize:
 
-```swift
-/// Determines the appearance of the bottom sheet.
-public struct Appearance {
-    /// Appearance of the drag indicator.
-    public var indicatorAppearance: DragIndicatorView.Appearance?
-    /// Appearance of the sheet header view.
-    public var headerAppearance: SheetHeaderView.Appearance?
-    /// Bottom sheet layout properties such as corner radius. Default is `.default`.
-    public let layout: Layout
-    /// Bottom sheet's shadow. Default is `nil` (no shadow).
-    public let elevation: Elevation?
-    /// Dimmer view color. Default is 'UIColor.black.withAlphaComponent(0.5)'.
-    public let dimmerColor: UIColor?
-    /// Animation duration on bottom sheet. Default is `0.3`.
-    public let animationDuration: TimeInterval
-    /// Animation type during presenting. Default is `curveEaseIn`.
-    public let presentAnimationCurve: UIView.AnimationOptions
-    /// Animation type during dismissing. Default is `curveEaseOut`.
-    public let dismissAnimationCurve: UIView.AnimationOptions
-    /// (Optional) Minimum content view height. Default is `nil`.
-    ///
-    /// Only applicable for resizable sheets. `nil` means to use the content view's intrinsic height as the minimum.
-    public var minimumContentHeight: CGFloat?
-}
-```
+* drag indicator (whether you have one at all or what its size and color are)
+* header (whether you have one at all or what its text color, typography, and optional close button image are)
+* layout (corner radius and minimum, maximum, and ideal sizes for the sheet's contents)
+* drop shadow (if any)
+* dimmer color
+* present animation
+* dismiss animation
 
 **Update or customize appearance**
 
@@ -133,8 +102,12 @@ sheet.appearance.elevation = Elevation(
     color: .black,
     opacity: 0.4
 )
+sheet.appearance.presentAnimation = Animation(
+    duration: 0.4, 
+    curve: .spring(damping: 0.6, velocity: 0.4)
+)
 
-// Present the sheet.
+// Present the sheet with a spring animation.
 present(sheet, animated: true)
 ```
 

Sources/YBottomSheet/Animation/Animation+BottomSheet.swift

@@ -0,0 +1,18 @@
+//
+//  Animation+BottomSheet.swift
+//  YBottomSheet
+//
+//  Created by Mark Pospesel on 5/4/23.
+//  Copyright © 2023 Y Media Labs. All rights reserved.
+//
+
+import YCoreUI
+
+/// Default animations for bottom sheets
+public extension Animation {
+    /// Default animation for presenting a bottom sheet
+    static let defaultPresent = Animation(curve: .regular(options: .curveEaseIn))
+
+    /// Default animation for dismissing a bottom sheet
+    static let defaultDismiss = Animation(curve: .regular(options: .curveEaseOut))
+}

Sources/YBottomSheet/Animation/BottomSheetAnimator.swift

@@ -13,6 +13,14 @@ class BottomSheetAnimator: NSObject {
     /// Bottom sheet controller.
     let sheetViewController: BottomSheetController
 
+    enum Direction {
+        case present
+        case dismiss
+    }
+
+    /// Animation direction (present or dismiss)
+    let direction: Direction
+
     /// Override for isReduceMotionEnabled. Default is `nil`.
     ///
     /// For unit testing. When non-`nil` it will be returned instead of
@@ -25,16 +33,24 @@ class BottomSheetAnimator: NSObject {
     }
 
     /// Initializes a bottom sheet animator.
-    /// - Parameter sheetViewController: the sheet being animated.
-    init(sheetViewController: BottomSheetController) {
+    /// - Parameters:
+    ///   - sheetViewController: the sheet being animated.
+    ///   - direction: animation direction
+    init(sheetViewController: BottomSheetController, direction: Direction) {
         self.sheetViewController = sheetViewController
+        self.direction = direction
         super.init()
     }
 }
 
 extension BottomSheetAnimator: UIViewControllerAnimatedTransitioning {
     func transitionDuration(using transitionContext: UIViewControllerContextTransitioning?) -> TimeInterval {
-        sheetViewController.appearance.animationDuration
+        switch direction {
+        case .present:
+            return sheetViewController.appearance.presentAnimation.duration
+        case .dismiss:
+            return sheetViewController.appearance.dismissAnimation.duration
+        }
     }
 
     // Override this method and perform the animations

Sources/YBottomSheet/Animation/BottomSheetDismissAnimator.swift

@@ -10,6 +10,12 @@ import UIKit
 
 /// Performs the sheet dismiss animation.
 class BottomSheetDismissAnimator: BottomSheetAnimator {
+    /// Initializes a bottom sheet animator.
+    /// - Parameter sheetViewController: the sheet being animated.
+    required init(sheetViewController: BottomSheetController) {
+        super.init(sheetViewController: sheetViewController, direction: .dismiss)
+    }
+
     override func animateTransition(using transitionContext: UIViewControllerContextTransitioning) {
         guard let fromViewController = transitionContext.viewController(forKey: .from),
               let toViewController = transitionContext.viewController(forKey: .to) else {
@@ -31,12 +37,8 @@ class BottomSheetDismissAnimator: BottomSheetAnimator {
         ) {
             sheet.dimmerView.alpha = 0
         }
-
-        UIView.animate(
-            withDuration: duration,
-            delay: .zero,
-            options: [.beginFromCurrentState, sheet.appearance.dismissAnimationCurve]
-        ) {
+
+        UIView.animate(with: sheet.appearance.dismissAnimation) {
             if self.isReduceMotionEnabled {
                 sheet.sheetView.alpha = 0
             } else {

Sources/YBottomSheet/Animation/BottomSheetPresentAnimator.swift

@@ -10,6 +10,12 @@ import UIKit
 
 /// Performs the sheet present animation.
 class BottomSheetPresentAnimator: BottomSheetAnimator {
+    /// Initializes a bottom sheet animator.
+    /// - Parameter sheetViewController: the sheet being animated.
+    required init(sheetViewController: BottomSheetController) {
+        super.init(sheetViewController: sheetViewController, direction: .present)
+    }
+
     override func animateTransition(using transitionContext: UIViewControllerContextTransitioning) {
         guard let toViewController = transitionContext.viewController(forKey: .to) else {
             transitionContext.completeTransition(false)
@@ -44,11 +50,7 @@ class BottomSheetPresentAnimator: BottomSheetAnimator {
             sheet.dimmerView.alpha = 1
         }
 
-        UIView.animate(
-            withDuration: duration,
-            delay: .zero,
-            options: [.beginFromCurrentState, sheet.appearance.presentAnimationCurve]
-        ) {
+        UIView.animate(with: sheet.appearance.presentAnimation) {
             if self.isReduceMotionEnabled {
                 sheet.sheetView.alpha = 1
             } else {

Sources/YBottomSheet/BottomSheetController+Appearance.swift

@@ -22,13 +22,10 @@ extension BottomSheetController {
         public var elevation: Elevation?
         /// Dimmer view color. Default is 'UIColor.black.withAlphaComponent(0.5)'.
         public var dimmerColor: UIColor?
-        /// Animation duration on bottom sheet. Default is `0.3`.
-        public var animationDuration: TimeInterval
-        /// Animation type during presenting. Default is `curveEaseIn`.
-        public var presentAnimationCurve: UIView.AnimationOptions
-        /// Animation type during dismissing. Default is `curveEaseOut`.
-        public var dismissAnimationCurve: UIView.AnimationOptions
-        /// Whether the sheet can be dismissed by swiping down or tapping on the dimmer. Default is `true`.
+        /// Animation for presenting the bottom sheet. Default = `.defaultPresent`.
+        public var presentAnimation: Animation
+        /// Animation for dismissing the bottom sheet. Default = `.defaultDismiss`.
+        public var dismissAnimation: Animation
         ///
         /// The user can always dismiss the sheet from the close button if it is visible.
         public var isDismissAllowed: Bool
@@ -43,31 +40,28 @@ extension BottomSheetController {
         ///   - indicatorAppearance: appearance of the drag indicator or pass `nil` to hide.
         ///   - headerAppearance: appearance of the sheet header view or pass `nil` to hide.
         ///   - layout: bottom sheet layout properties such as corner radius.
-        ///   - elevation: bottom sheet's shadow or pass `nil` to hide
+        ///   - elevation: bottom sheet's shadow or pass `nil` to hide.
         ///   - dimmerColor: dimmer view color or pass `nil` to hide.
-        ///   - animationDuration: animation duration for bottom sheet. Default is `0.3`.
-        ///   - presentAnimationCurve: animation type during presenting.
-        ///   - dismissAnimationCurve: animation type during dismiss.
+        ///   - presentAnimation: animation for presenting the bottom sheet.
+        ///   - dismissAnimation: animation for dismissing the bottom sheet.
         ///   - isDismissAllowed: whether the sheet can be dismissed by swiping down or tapping on the dimmer.
         public init(
             indicatorAppearance: DragIndicatorView.Appearance? = nil,
             headerAppearance: SheetHeaderView.Appearance? = .default,
             layout: Layout = .default,
             elevation: Elevation? = nil,
             dimmerColor: UIColor? = .black.withAlphaComponent(0.5),
-            animationDuration: TimeInterval = 0.3,
-            presentAnimationCurve: UIView.AnimationOptions = .curveEaseIn,
-            dismissAnimationCurve: UIView.AnimationOptions = .curveEaseOut,
+            presentAnimation: Animation = .defaultPresent,
+            dismissAnimation: Animation = .defaultDismiss,
             isDismissAllowed: Bool = true
         ) {
             self.indicatorAppearance = indicatorAppearance
             self.headerAppearance = headerAppearance
             self.layout = layout
             self.elevation = elevation
             self.dimmerColor = dimmerColor
-            self.animationDuration = animationDuration
-            self.presentAnimationCurve = presentAnimationCurve
-            self.dismissAnimationCurve = dismissAnimationCurve
+            self.presentAnimation = presentAnimation
+            self.dismissAnimation = dismissAnimation
             self.isDismissAllowed = isDismissAllowed
         }
     }

Tests/YBottomSheetTests/Animation/Animation+BottomSheetTests.swift

@@ -0,0 +1,33 @@
+//
+//  Animation+BottomSheetTests.swift
+//  YBottomSheet
+//
+//  Created by Mark Pospesel on 5/4/23.
+//  Copyright © 2023 Y Media Labs. All rights reserved.
+//
+
+import XCTest
+import YCoreUI
+@testable import YBottomSheet
+
+final class AnimationBottomSheetTests: XCTestCase {
+    func test_defaultPresent() {
+        // Given
+        let sut = Animation.defaultPresent
+
+        // Then
+        XCTAssertEqual(sut.duration, 0.3)
+        XCTAssertEqual(sut.delay, 0.0)
+        XCTAssertEqual(sut.curve, .regular(options: .curveEaseIn))
+    }
+
+    func test_defaultDismiss() {
+        // Given
+        let sut = Animation.defaultDismiss
+
+        // Then
+        XCTAssertEqual(sut.duration, 0.3)
+        XCTAssertEqual(sut.delay, 0.0)
+        XCTAssertEqual(sut.curve, .regular(options: .curveEaseOut))
+    }
+}

Tests/YBottomSheetTests/Animation/BottomSheetAnimatorTests.swift

@@ -17,13 +17,22 @@ final class BottomSheetAnimatorTests: XCTestCase {
         XCTAssertEqual(sut.sheetViewController, sheetController)
     }
 
-    func test_duration() {
+    func test_presentDuration() {
         let main = UIViewController()
         let sheetController = BottomSheetController(title: "Bottom Sheet", childView: UIView())
-        let sut = makeSUT(sheetViewController: sheetController)
+        let sut = makeSUT(sheetViewController: sheetController, direction: .present)
+        let context = MockAnimationContext(from: main, to: sheetController)
+
+        XCTAssertEqual(sut.transitionDuration(using: context), sheetController.appearance.presentAnimation.duration)
+    }
+
+    func test_dismissDuration() {
+        let main = UIViewController()
+        let sheetController = BottomSheetController(title: "Bottom Sheet", childView: UIView())
+        let sut = makeSUT(sheetViewController: sheetController, direction: .dismiss)
         let context = MockAnimationContext(from: main, to: sheetController)
 
-        XCTAssertEqual(sut.transitionDuration(using: context), sheetController.appearance.animationDuration)
+        XCTAssertEqual(sut.transitionDuration(using: context), sheetController.appearance.dismissAnimation.duration)
     }
 
     func test_animate() {
@@ -42,10 +51,11 @@ final class BottomSheetAnimatorTests: XCTestCase {
 private extension BottomSheetAnimatorTests {
     func makeSUT(
         sheetViewController: BottomSheetController,
+        direction: BottomSheetAnimator.Direction = .present,
         file: StaticString = #filePath,
         line: UInt = #line
     ) -> BottomSheetAnimator {
-        let sut = BottomSheetAnimator(sheetViewController: sheetViewController)
+        let sut = BottomSheetAnimator(sheetViewController: sheetViewController, direction: direction)
         trackForMemoryLeak(sut, file: file, line: line)
         return sut
     }

Tests/YBottomSheetTests/Animation/BottomSheetDismissAnimatorTests.swift

@@ -7,13 +7,15 @@
 //
 
 import XCTest
+import YCoreUI
 @testable import YBottomSheet
 
 final class BottomSheetDismissAnimatorTests: XCTestCase {
     func test_animate() throws {
         let sheetController = makeSheet()
         let (sut, context) = try makeSUT(sheetViewController: sheetController, to: sheetController)
 
+        XCTAssertEqual(sut.transitionDuration(using: context), 0.0)
         XCTAssertTrue(sut is BottomSheetDismissAnimator)
         XCTAssertFalse(context.wasCompleteCalled)
         sut.animateTransition(using: context)
@@ -32,6 +34,7 @@ final class BottomSheetDismissAnimatorTests: XCTestCase {
             isReduceMotionEnabled: false
         )
 
+        XCTAssertEqual(sut.transitionDuration(using: context), 0.0)
         sut.animateTransition(using: context)
 
         // Wait for the run loop to tick (animate keyboard)
@@ -49,6 +52,7 @@ final class BottomSheetDismissAnimatorTests: XCTestCase {
             isReduceMotionEnabled: true
         )
 
+        XCTAssertEqual(sut.transitionDuration(using: context), 0.0)
         sut.animateTransition(using: context)
 
         // Wait for the run loop to tick (animate keyboard)
@@ -62,6 +66,7 @@ final class BottomSheetDismissAnimatorTests: XCTestCase {
         let sheetController = makeSheet()
         let (sut, context) = try makeSUT(sheetViewController: sheetController, to: nil)
 
+        XCTAssertEqual(sut.transitionDuration(using: context), 0.0)
         XCTAssertFalse(context.wasCompleteCalled)
         sut.animateTransition(using: context)
 
@@ -96,7 +101,9 @@ private extension BottomSheetDismissAnimatorTests {
         let sheet = BottomSheetController(
             title: "Bottom Sheet",
             childView: UIView(),
-            appearance: BottomSheetController.Appearance(animationDuration: 0.0)
+            appearance: BottomSheetController.Appearance(
+                dismissAnimation: Animation(duration: 0.0, curve: .regular(options: .curveEaseOut))
+            )
         )
         trackForMemoryLeak(sheet)
         return sheet