Add scroll bar offset and content insets

DMScrollBar/DMScrollBar.swift

@@ -113,7 +113,11 @@ public class DMScrollBar: UIView {
             scrollIndicatorTopConstraint = scrollIndicator.topAnchor.constraint(equalTo: topAnchor, constant: topOffset)
             scrollIndicatorTopConstraint?.isActive = true
         }
-        scrollIndicator.setup(stateConfig: stateConfig, textConfig: indicatorTextConfig)
+        scrollIndicator.setup(
+            stateConfig: stateConfig,
+            textConfig: indicatorTextConfig,
+            accessibilityIdentifier: configuration.indicator.accessibilityIdentifier
+        )
     }
 
     private func setupAdditionalInfoView() {
@@ -494,6 +498,10 @@ public class DMScrollBar: UIView {
         return panGestureRecognizer?.state.isInactive == true
     }
 
+    private func scrollIndicatorOffset(forContentOffset contentOffset: CGFloat) -> CGFloat {
+        return contentOffset + scrollIndicatorTopOffset.y + infoView.frame.height / 2
+    }
+
     private func startHideTimerIfNeeded() {
         guard isPanGestureInactive else { return }
         invalidateHideTimer()
@@ -513,7 +521,10 @@ public class DMScrollBar: UIView {
 
     private func updateAdditionalInfoViewState(forScrollOffset scrollViewOffset: CGFloat, previousOffset: CGFloat?) {
         if configuration.infoLabel == nil { return }
-        guard let offsetLabelText = delegate?.infoLabelText(forOffset: scrollViewOffset) else { return animateAdditionalInfoViewHide() }
+        guard let offsetLabelText = delegate?.infoLabelText(
+            forContentOffset: scrollViewOffset,
+            scrollIndicatorOffset: scrollIndicatorOffset(forContentOffset: scrollViewOffset)
+        ) else { return animateAdditionalInfoViewHide() }
         animateAdditionalInfoViewShow()
         let direction: CATransitionSubtype? = {
             guard let previousOffset else { return nil }
@@ -533,7 +544,10 @@ public class DMScrollBar: UIView {
         }()
         scrollIndicator.updateScrollIndicatorText(
             direction: direction,
-            scrollBarLabelText: delegate?.scrollBarText(forOffset: scrollViewOffset),
+            scrollBarLabelText: delegate?.scrollBarText(
+                forContentOffset: scrollViewOffset,
+                scrollIndicatorOffset: scrollIndicatorOffset(forContentOffset: scrollViewOffset)
+            ),
             textConfig: textConfig
         )
     }

DMScrollBar/DMScrollBarConfiguration.swift

@@ -71,6 +71,9 @@ extension DMScrollBar.Configuration {
         /// Top left and bottom left corners will be rounded by a radius equal to half the view's height
         public static let roundedLeftCorners = RoundedCorners(radius: .rounded, corners: [.topLeft, .bottomLeft])
 
+        /// Top right and bottom right corners will be rounded by a radius equal to half the view's height
+        public static let roundedRightCorners = RoundedCorners(radius: .rounded, corners: [.topRight, .bottomRight])
+
         /// All corners will be rounded by a radius equal to half the view's height
         public static let allRounded = RoundedCorners(radius: .rounded, corners: Set(Corner.allCases))
 
@@ -147,24 +150,30 @@ extension DMScrollBar.Configuration {
         /// Scroll bar indicator show / hide animation settings
         public let animation: Animation
 
+        /// Accessibility identifier of the indicator
+        public let accessibilityIdentifier: String?
+
         /// - Parameters:
         ///   - normalState: Configuration for indicator state while the user is not interacting with it
         ///   - activeState: Configuration for indicator state while the user interacting with it
         ///   - stateChangeAnimationDuration: Time in seconds for the state change animation to take place
         ///   - insetsFollowsSafeArea: Indicates if safe area insets should be taken into account
         ///   - animation: Scroll bar indicator show / hide animation settings
+        ///   - accessibilityIdentifier: Accessibility identifier of the indicator
         public init(
             normalState: StateConfig = .default,
             activeState: ActiveStateConfig = .unchanged,
             stateChangeAnimationDuration: TimeInterval = 0.3,
             insetsFollowsSafeArea: Bool = true,
-            animation: Animation = .default
+            animation: Animation = .default,
+            accessibilityIdentifier: String? = nil
         ) {
             self.normalState = normalState
             self.activeState = activeState
             self.stateChangeAnimationDuration = stateChangeAnimationDuration
             self.insetsFollowsSafeArea = insetsFollowsSafeArea
             self.animation = animation
+            self.accessibilityIdentifier = accessibilityIdentifier
         }
 
         /// Default indicator configuration
@@ -180,35 +189,47 @@ extension DMScrollBar.Configuration {
             /// Scroll bar indicator insets
             public let insets: UIEdgeInsets
 
+            /// Scroll bar indicator content insets
+            public let contentInsets: UIEdgeInsets
+
             /// Scroll bar image
             public let image: UIImage?
 
             /// Scroll bar image size
             public let imageSize: CGSize
 
+            /// Accessibility identifier of the image
+            public let imageAccessibilityIdentifier: String?
+
             /// Scroll bar indicator corners which should be rounded
             public let roundedCorners: RoundedCorners
 
             /// - Parameters:
             ///   - size: Size of the scroll bar indicator, which is placed on the right side
             ///   - backgroundColor: Background color of the scroll bar indicator
             ///   - insets: Scroll bar indicator insets
+            ///   - contentInsets: Scroll bar indicator content insets
             ///   - image: Scroll bar image
             ///   - imageSize: Scroll bar image size. If a nil image is passed - this parameter is ignored
+            ///   - imageAccessibilityIdentifier: Accessibility identifier of the image
             ///   - roundedCorners: Scroll bar indicator corners which should be rounded
             public init(
                 size: CGSize = CGSize(width: 34, height: 34),
                 backgroundColor: UIColor = UIColor.defaultScrollBarBackground,
                 insets: UIEdgeInsets = UIEdgeInsets(top: 8, left: 0, bottom: 8, right: 0),
+                contentInsets: UIEdgeInsets = UIEdgeInsets(top: 8, left: 8, bottom: 8, right: 8),
                 image: UIImage? = UIImage(systemName: "arrow.up.and.down.circle")?.withRenderingMode(.alwaysOriginal).withTintColor(UIColor.systemBackground),
                 imageSize: CGSize = CGSize(width: 20, height: 20),
+                imageAccessibilityIdentifier: String? = nil,
                 roundedCorners: RoundedCorners = .roundedLeftCorners
             ) {
                 self.size = size
                 self.backgroundColor = backgroundColor
                 self.insets = insets
+                self.contentInsets = contentInsets
                 self.image = image
                 self.imageSize = imageSize
+                self.imageAccessibilityIdentifier = imageAccessibilityIdentifier
                 self.roundedCorners = roundedCorners
             }
 
@@ -221,6 +242,7 @@ extension DMScrollBar.Configuration {
                     size: .init(width: width, height: 100),
                     backgroundColor: UIColor.label.withAlphaComponent(0.35),
                     insets: .init(top: 4, left: 0, bottom: 4, right: 2),
+                    contentInsets: .zero,
                     image: nil,
                     roundedCorners: .allRounded
                 )
@@ -245,19 +267,24 @@ extension DMScrollBar.Configuration {
                 public let font: UIFont
                 /// Text color of the label
                 public let color: UIColor
+                /// Accessibility identifier of the label
+                public let accessibilityIdentifier: String?
 
                 /// - Parameters:
                 ///   - insets: Text label insets from
                 ///   - font: Font that should be used for text
                 ///   - color: Text color of the label
+                ///   - accessibilityIdentifier: Accessibility identifier of the label
                 public init(
                     insets: UIEdgeInsets,
                     font: UIFont,
-                    color: UIColor
+                    color: UIColor,
+                    accessibilityIdentifier: String? = nil
                 ) {
                     self.insets = insets
                     self.font = font
                     self.color = color
+                    self.accessibilityIdentifier = accessibilityIdentifier
                 }
             }
         }
@@ -288,6 +315,9 @@ extension DMScrollBar.Configuration {
         /// Info label show/hide animation settings
         public let animation: Animation
 
+        /// Accessibility identifier of the info label
+        public let accessibilityIdentifier: String?
+
         /// - Parameters:
         ///   - font: Indicates the font that should be used for info label, which appears during indicator scrolling
         ///   - textColor: Text color of the info label
@@ -297,6 +327,7 @@ extension DMScrollBar.Configuration {
         ///   - maximumWidth: Indicates maximum width of info label. If nil is passed - the info label will grow maximum to the leading side of the screen
         ///   - roundedCorners: Info label corenrs which should be rounded
         ///   - animation: Info label show/hide animation settings
+        ///   - accessibilityIdentifier: Accessibility identifier of the info label
         public init(
             font: UIFont = UIFont.systemFont(ofSize: 13),
             textColor: UIColor = UIColor.systemBackground,
@@ -305,7 +336,8 @@ extension DMScrollBar.Configuration {
             textInsets: UIEdgeInsets = UIEdgeInsets(top: 6, left: 10, bottom: 6, right: 10),
             maximumWidth: CGFloat? = nil,
             roundedCorners: RoundedCorners = .allRounded,
-            animation: Animation = .default
+            animation: Animation = .default,
+            accessibilityIdentifier: String? = nil
         ) {
             self.font = font
             self.textColor = textColor
@@ -315,6 +347,7 @@ extension DMScrollBar.Configuration {
             self.maximumWidth = maximumWidth
             self.roundedCorners = roundedCorners
             self.animation = animation
+            self.accessibilityIdentifier = accessibilityIdentifier
         }
 
         /// Default info label configuration

DMScrollBar/DMScrollBarDelegate.swift

@@ -2,20 +2,24 @@ import UIKit
 
 public protocol DMScrollBarDelegate: AnyObject {
     /// This method is triggered every time when scroll bar offset changes while the user is dragging it
-    /// - Parameter offset: Scroll view content offset
+    /// - Parameter contentOffset: Scroll view content offset
+    /// - Parameter scrollIndicatorOffset: Scroll indicator offset
     /// - Returns: Text to present in info label (which appears during indicator scrolling to the left of the Scroll Bar) . If returning nil - the info label will not show
-    func infoLabelText(forOffset offset: CGFloat) -> String?
+    func infoLabelText(forContentOffset contentOffset: CGFloat, scrollIndicatorOffset: CGFloat) -> String?
 
     /// This method is triggered every time when scroll bar offset changes while the user is dragging it
-    /// - Parameter offset: Scroll view content offset
+    /// - Parameter contentOffset: Scroll view content offset
+    /// - Parameter scrollIndicatorOffset: Scroll indicator offset
     /// - Returns: Text to present in scroll bar label. This method is not triggered when Configuration.Indicator.StateConfig.TextConfig is nil.
-    func scrollBarText(forOffset offset: CGFloat) -> String?
+    func scrollBarText(forContentOffset contentOffset: CGFloat, scrollIndicatorOffset: CGFloat) -> String?
 }
 
 // MARK: - DMScrollBarDelegate extension for Table View
 
 public extension DMScrollBarDelegate {
-    func scrollBarText(forOffset offset: CGFloat) -> String? { nil }
+    func infoLabelText(forContentOffset contentOffset: CGFloat, scrollIndicatorOffset: CGFloat) -> String? { nil }
+
+    func scrollBarText(forContentOffset contentOffset: CGFloat, scrollIndicatorOffset: CGFloat) -> String? { nil }
 
     /// This is a convenience method to get the header title for the section at the specified content offset. This method will not work for table views with custom headers
     /// - Parameters:
@@ -43,4 +47,46 @@ public extension DMScrollBarDelegate {
             return minY...maxY ~= offset
         }
     }
+
+    /// This is a convenience method to get section index for specified collection view content offset
+    /// - Parameters:
+    ///   - collectionView: Collection view in which the scroll bar is located
+    ///   - offset: Collection View content offset
+    /// - Returns: Section index in collection view for specified collection view content offset
+    func sectionIndex(in collectionView: UICollectionView, forOffset offset: CGFloat) -> Int? {
+        (0..<collectionView.numberOfSections).first { section in
+            guard let currentSectionOrigin = headerOrigin(in: collectionView, atSection: section) else { return false }
+            let nextSectionOrigin = headerOrigin(in: collectionView, atSection: section + 1)
+            let sectionHeight = (nextSectionOrigin?.y ?? .greatestFiniteMagnitude) - currentSectionOrigin.y
+            let sectionSize = CGSize(width: collectionView.frame.width, height: sectionHeight)
+            let sectionRect = CGRect(origin: currentSectionOrigin, size: sectionSize)
+            let minY: CGFloat = section == 0 ? -.greatestFiniteMagnitude : sectionRect.minY
+            let maxY: CGFloat = section == collectionView.numberOfSections - 1 ?
+                .greatestFiniteMagnitude :
+                sectionRect.maxY
+
+            return minY...maxY ~= offset
+        }
+    }
+
+    // MARK: - Private
+
+    private func headerOrigin(in collectionView: UICollectionView, atSection section: Int) -> CGPoint? {
+        let indexPath = IndexPath(item: 0, section: section)
+        let kind = UICollectionView.elementKindSectionHeader
+        guard isValid(indexPath: indexPath, in: collectionView) else { return nil }
+        guard let attributes = collectionView.layoutAttributesForSupplementaryElement(
+            ofKind: kind,
+            at: indexPath
+        ) else { return nil }
+
+        return attributes.frame.origin
+    }
+
+    private func isValid(indexPath: IndexPath, in collectionView: UICollectionView) -> Bool {
+        guard indexPath.section < collectionView.numberOfSections else { return false }
+        let numberOfItems = collectionView.numberOfItems(inSection: indexPath.section)
+
+        return indexPath.row < numberOfItems || numberOfItems == 0
+    }
 }

DMScrollBar/ScrollBarIndicator.swift

@@ -39,8 +39,11 @@ final class ScrollBarIndicator: UIView {
 
     func setup(
         stateConfig: DMScrollBar.Configuration.Indicator.StateConfig,
-        textConfig: DMScrollBar.Configuration.Indicator.ActiveStateConfig.TextConfig?
+        textConfig: DMScrollBar.Configuration.Indicator.ActiveStateConfig.TextConfig?,
+        accessibilityIdentifier: String? = nil
     ) {
+        self.accessibilityIdentifier = accessibilityIdentifier
+        self.isAccessibilityElement = false
         backgroundColor = stateConfig.backgroundColor
         layer.maskedCorners = stateConfig.roundedCorners.corners.cornerMask
         layer.cornerRadius = cornerRadius(
@@ -54,10 +57,9 @@ final class ScrollBarIndicator: UIView {
             centerX.isActive = true
             indicatorImageLabelStackView.centerYAnchor.constraint(equalTo: centerYAnchor).isActive = true
         }
-        let defaultInset: CGFloat = 8
         let leadingInset: CGFloat = {
-            guard let textConfig else { return 0 }
-            return stateConfig.image == nil ? textConfig.insets.left : defaultInset
+            guard let textConfig else { return stateConfig.contentInsets.left }
+            return stateConfig.image == nil ? textConfig.insets.left : stateConfig.contentInsets.left
         }()
         setupConstraint(
             constraint: &indicatorImageLabelStackViewLeadingConstraint,
@@ -67,9 +69,9 @@ final class ScrollBarIndicator: UIView {
         setupConstraint(
             constraint: &indicatorImageLabelStackViewTrailingConstraint,
             build: { trailingAnchor.constraint(equalTo: indicatorImageLabelStackView.trailingAnchor, constant: $0) },
-            value: textConfig != nil ? textConfig?.insets.right ?? defaultInset : 0
+            value: textConfig?.insets.right ?? stateConfig.contentInsets.right
         )
-        setupIndicatorImageViewState(image: stateConfig.image, size: stateConfig.imageSize)
+        setupIndicatorImageViewState(config: stateConfig)
         setupIndicatorLabelState(config: textConfig)
     }
 
@@ -87,22 +89,23 @@ final class ScrollBarIndicator: UIView {
 
     // MARK: - Private
 
-    private func setupIndicatorImageViewState(image: UIImage?, size: CGSize) {
+    private func setupIndicatorImageViewState(config: DMScrollBar.Configuration.Indicator.StateConfig) {
         buildIndicatorImageViewIfNeeded()
-        if let image {
+        if let image = config.image {
             indicatorImage?.isHidden = false
             indicatorImage?.alpha = 1
             indicatorImage?.image = image
+            indicatorImage?.accessibilityIdentifier = config.imageAccessibilityIdentifier
             setupConstraint(
                 constraint: &indicatorImageWidthConstraint,
                 build: indicatorImage?.widthAnchor.constraint(equalToConstant:),
-                value: size.width,
+                value: config.imageSize.width,
                 priority: .init(999)
             )
             setupConstraint(
                 constraint: &indicatorImageHeightConstraint,
                 build: indicatorImage?.heightAnchor.constraint(equalToConstant:),
-                value: size.height
+                value: config.imageSize.height
             )
         } else {
             indicatorImage?.isHidden = true
@@ -116,6 +119,7 @@ final class ScrollBarIndicator: UIView {
             showIndicatorLabel()
             indicatorLabel?.font = config.font
             indicatorLabel?.textColor = config.color
+            indicatorLabel?.accessibilityIdentifier = config.accessibilityIdentifier
             indicatorImageLabelStackView.spacing = config.insets.left
         } else {
             hideIndicatorLabel()

DMScrollBar/ScrollBarInfoView.swift

@@ -33,6 +33,7 @@ final class ScrollBarInfoView: UIView {
         offsetLabel.bottomAnchor.constraint(equalTo: bottomAnchor, constant: -textInsets.bottom).isActive = true
         offsetLabel.leadingAnchor.constraint(equalTo: leadingAnchor, constant: textInsets.left).isActive = true
         offsetLabel.trailingAnchor.constraint(equalTo: trailingAnchor, constant: -textInsets.right).isActive = true
+        offsetLabel.accessibilityIdentifier = config.accessibilityIdentifier
 
         backgroundColor = config.backgroundColor
         layer.maskedCorners = config.roundedCorners.corners.cornerMask

Example/DMScrollBar/ViewController.swift

@@ -203,13 +203,13 @@ extension ViewController: UITableViewDataSource {
 
 extension ViewController: DMScrollBarDelegate {
     /// In this example, this method returns the section header title for the top visible section
-    func infoLabelText(forOffset offset: CGFloat) -> String? {
-        headerTitle(in: tableView, forOffset: offset)
+    func infoLabelText(forContentOffset contentOffset: CGFloat, scrollIndicatorOffset: CGFloat) -> String? {
+        headerTitle(in: tableView, forOffset: contentOffset)
     }
 
     /// In this example, this method returns the section header title for the top visible section
-    func scrollBarText(forOffset offset: CGFloat) -> String? {
-        guard let section = sectionIndex(in: tableView, forOffset: offset) else { return nil }
+    func scrollBarText(forContentOffset contentOffset: CGFloat, scrollIndicatorOffset: CGFloat) -> String? {
+        guard let section = sectionIndex(in: tableView, forOffset: contentOffset) else { return nil }
         return shortHeaderDateFormatter.string(from: sections[section].date).capitalized
     }
 }