Digital ACT-191 ONEAPP-6830 story: Implementation for scroll thumb on given position value

VDS/Components/CarouselScrollbar/CarouselScrollbar.swift

@@ -44,11 +44,12 @@ open class CarouselScrollbar: View {
                 _numberOfSlides = 1
             }
             setThumbWidth()
+            setThumb(position)
             setNeedsUpdate()
         }
     }
     
-    /// The amount of slides visible in the carousel container at one time.
+    /// The number of slides that can appear at once in a set in a carousel container.
     open var selectedLayout: Layout? {
         get { return _selectedLayout }
         set {
@@ -58,11 +59,12 @@ open class CarouselScrollbar: View {
                 _selectedLayout = .oneUP
             }
             setThumbWidth()
+            setThumb(position)
             setNeedsUpdate()
         }
     }
     
-    /// Enum used to describe the amount of slides visible in the carousel container at one time.
+    /// Enum used to describe the number of slides that can appear at once in a set in a carousel container.
     public enum Layout: String, CaseIterable {
         case oneUP = "1UP"
         case twoUP = "2UP"
@@ -93,7 +95,19 @@ open class CarouselScrollbar: View {
     }
     
     /// Used to set the position of the thumb(scrubber). This is used when the carousel container changes position, it will align the position of thumb(scrubber).
-    open var position: Int?  { didSet { setNeedsUpdate() } }
+    open var position: Int? {
+        get { return _position }
+        set {
+            if let newValue {
+                checkPositions()
+                _position = (newValue > totalPositions ?? 1) ? totalPositions : newValue
+            } else {
+                _position = 1
+            }
+            setThumb(position)
+            setNeedsUpdate()
+        }
+    }
     
     /// Allows a unique id to be passed into the thumb and track of the thumb(scrubber).
     open var scrubberId: Int?  { didSet { setNeedsUpdate() } }
@@ -107,7 +121,9 @@ open class CarouselScrollbar: View {
     internal var _selectedLayout: Layout = .oneUP
     internal var _numberOfSlides: Int? = 1
     internal var heightConstraint: NSLayoutConstraint?
-
+    internal var totalPositions: Int? = 1
+    internal var _position: Int? = 1
+    
     private let trackViewWidth = 96
     private let trackViewHeight: CGFloat = 4
     private let minThumbWidth: Float = 16.0
@@ -179,7 +195,7 @@ open class CarouselScrollbar: View {
         leftActiveOverlay.frame = CGRectMake(trackView.frame.origin.x, 20,  CGFloat(trackViewWidth), trackViewHeight)
         leftActiveOverlay.isUserInteractionEnabled = true
         leftActiveOverlay.layer.cornerRadius = cornerRadius
-        let leftPressRecognizer = UILongPressGestureRecognizer(target: self, action: #selector(self.leftLongPressed(_:)))
+        let leftPressRecognizer = UILongPressGestureRecognizer(target: self, action: #selector(self.onThumbTouchStart(_:)))
         leftPressRecognizer.minimumPressDuration = 0
         leftActiveOverlay.addGestureRecognizer(leftPressRecognizer)
         addSubview(leftActiveOverlay)
@@ -188,7 +204,7 @@ open class CarouselScrollbar: View {
         rightActiveOverlay.frame = CGRectMake(thumbView.frame.origin.x + thumbView.frame.size.width, 20,  CGFloat(trackViewWidth), trackViewHeight)
         rightActiveOverlay.isUserInteractionEnabled = true
         rightActiveOverlay.layer.cornerRadius = cornerRadius
-        let rightPressRecognizer = UILongPressGestureRecognizer(target: self, action: #selector(self.rightLongPressed(_:)))
+        let rightPressRecognizer = UILongPressGestureRecognizer(target: self, action: #selector(self.onThumbTouchEnd(_:)))
         rightPressRecognizer.minimumPressDuration = 0
         rightActiveOverlay.addGestureRecognizer(rightPressRecognizer)
         addSubview(rightActiveOverlay)
@@ -198,7 +214,7 @@ open class CarouselScrollbar: View {
         thumbView.layer.cornerRadius = cornerRadius
         thumbView.addGestureRecognizer(UIPanGestureRecognizer(target: self, action:(#selector(self.handleGesture(_:)))))
         addSubview(thumbView)
-        updateActiveOverlayFrames()
+        updateActiveOverlays()
     }
     
     open override func updateView() {
@@ -223,17 +239,16 @@ open class CarouselScrollbar: View {
     //--------------------------------------------------
     // MARK: - Private Methods
     //--------------------------------------------------
-    func updateThumbViewToLeft() {
+    func onMoveBackward() {
         thumbView.frame.origin.x = thumbView.frame.origin.x - CGFloat(actualThumbWidth)
-        updateActiveOverlayFrames()
+        updateActiveOverlays()
     }
     
-    func updateThumbViewToRight() {
+    func onMoveForward() {
         thumbView.frame.origin.x = thumbView.frame.origin.x + CGFloat(actualThumbWidth)
-        updateActiveOverlayFrames()
+        updateActiveOverlays()
     }
-    
+
-    //TO DO: Drag functionality pending
     @objc func handleGesture(_ sender: UIPanGestureRecognizer) {
         
         switch sender.state {
@@ -254,7 +269,7 @@ open class CarouselScrollbar: View {
         }
     }
     
-    @objc func leftLongPressed(_ gesture: UILongPressGestureRecognizer) {
+    @objc func onThumbTouchStart(_ gesture: UILongPressGestureRecognizer) {
         if gesture.state == .began {
             leftActiveOverlay.backgroundColor = activeOverlayColorConfiguration.getColor(self)
             leftActiveOverlay.layer.opacity = activeOpacity
@@ -265,12 +280,12 @@ open class CarouselScrollbar: View {
             leftActiveOverlay.backgroundColor = .clear
             leftActiveOverlay.layer.opacity = defaultOpacity
             DispatchQueue.main.asyncAfter(deadline: .now() + .milliseconds(100)) { [weak self] in
-                self?.updateThumbViewToLeft()
+                self?.onMoveBackward()
             }
         }
     }
     
-    @objc func rightLongPressed(_ gesture: UILongPressGestureRecognizer) {
+    @objc func onThumbTouchEnd(_ gesture: UILongPressGestureRecognizer) {
         if gesture.state == .began {
             rightActiveOverlay.backgroundColor = activeOverlayColorConfiguration.getColor(self)
             rightActiveOverlay.layer.opacity = activeOpacity
@@ -281,21 +296,22 @@ open class CarouselScrollbar: View {
             rightActiveOverlay.backgroundColor = .clear
             rightActiveOverlay.layer.opacity = defaultOpacity
             DispatchQueue.main.asyncAfter(deadline: .now() + .milliseconds(100)) { [weak self] in
-                self?.updateThumbViewToRight()
+                self?.onMoveForward()
             }
         }
     }
     
     private func setThumbWidth() {
-        let width = Float (trackViewWidth / (numberOfSlides ?? 1) * _selectedLayout.value)
+        let width = (Float(trackViewWidth) / Float(numberOfSlides ?? 1)) * Float(_selectedLayout.value)
         actualThumbWidth = (width > Float(trackViewWidth)) ? Float(trackViewWidth) : width
         thumbWidth = (width <= Float(trackViewWidth) && width > minThumbWidth) ? width : ((width > Float(trackViewWidth)) ? Float(trackViewWidth) : minThumbWidth)
         thumbView.frame.size.width = CGFloat(thumbWidth)
         thumbView.frame.origin.x = trackView.frame.origin.x
-        updateActiveOverlayFrames()
+        checkPositions()
+        updateActiveOverlays()
     }
     
-    private func updateActiveOverlayFrames() {
+    private func updateActiveOverlays() {
         // adjusting thumb position if it goes beyond trackView.
         let thumbPosition = thumbView.frame.origin.x + thumbView.frame.size.width
         let trackPosition = trackView.frame.origin.x + trackView.frame.size.width
@@ -303,7 +319,7 @@ open class CarouselScrollbar: View {
             thumbView.frame.origin.x = trackPosition - thumbView.frame.size.width
         } else if thumbView.frame.origin.x < trackView.frame.origin.x {
             thumbView.frame.origin.x = trackView.frame.origin.x
-        } 
+        }
         
         //left active overlay position update
         leftActiveOverlay.frame.size.width = thumbView.frame.origin.x - trackView.frame.origin.x + cornerRadius
@@ -312,6 +328,15 @@ open class CarouselScrollbar: View {
         rightActiveOverlay.frame.origin.x = thumbView.frame.origin.x + thumbView.frame.size.width - cornerRadius
         rightActiveOverlay.frame.size.width = (trackView.frame.origin.x + trackView.frame.size.width) - (thumbView.frame.origin.x + thumbView.frame.size.width) + cornerRadius
     }
+    
+    private func checkPositions() {
+        totalPositions = Int (ceil (Double(numberOfSlides ?? 1) / Double(_selectedLayout.value)))
+    }
+    
+    private func setThumb(_ position: Int?) {
+        thumbView.frame.origin.x = CGFloat(Float((position ?? 1) - 1) * actualThumbWidth) + trackView.frame.origin.x
+        updateActiveOverlays()
+    }
 }