added publishers/cancellables

Signed-off-by: Matt Bruce <matt.bruce@verizon.com>

VDS/Components/CarouselScrollbar/CarouselScrollbar.swift

@@ -100,25 +100,99 @@ open class CarouselScrollbar: View {
             setNeedsUpdate()
         }
     }
-    
+        
     /// Allows a unique id to be passed into the thumb and track of the thumb(scrubber).
     open var scrubberId: Int?  { didSet { setNeedsUpdate() } }
     
     /// A callback when the scrubber position changes. Passes parameters (position).
-    open var onScrubberDrag: ((Int) -> Void)?
+    open var onScrubberDrag: ((Int) -> Void)? {
+        get { nil }
+        set {
+            onScrubberDragCancellable?.cancel()
+            if let newValue {
+                onScrubberDragCancellable = onScrubberDragPublisher
+                    .sink { c in
+                        newValue(c)
+                    }
+            }
+        }
+    }
+    
+    /// A publisher for when the scrubber position changes. Passes parameters (position).
+    open var onScrubberDragPublisher = PassthroughSubject<Int, Never>()
+    private var onScrubberDragCancellable: AnyCancellable?
 
     /// A callback when the thumb move forward. Passes parameters (position).
-    open var onMoveForward: ((Int) -> Void)?
+    open var onMoveForward: ((Int) -> Void)? {
+        get { nil }
+        set {
+            onMoveForwardCancellable?.cancel()
+            if let newValue {
+                onMoveForwardCancellable = onMoveForwardPublisher
+                    .sink { c in
+                        newValue(c)
+                    }
+            }
+        }
+    }
+    
+    /// A publisher for when the thumb move forward. Passes parameters (position).
+    open var onMoveForwardPublisher = PassthroughSubject<Int, Never>()
+    private var onMoveForwardCancellable: AnyCancellable?
 
     /// A callback when the thumb move backward. Passes parameters (position).
-    open var onMoveBackward: ((Int) -> Void)?
+    open var onMoveBackward: ((Int) -> Void)? {
+        get { nil }
+        set {
+            onMoveBackwardCancellable?.cancel()
+            if let newValue {
+                onMoveBackwardCancellable = onMoveBackwardPublisher
+                    .sink { c in
+                        newValue(c)
+                    }
+            }
+        }
+    }
+    
+    /// A publisher for when the thumb move backward. Passes parameters (position).
+    open var onMoveBackwardPublisher = PassthroughSubject<Int, Never>()
+    private var onMoveBackwardCancellable: AnyCancellable?
 
     /// A callback when the thumb touch start. Passes parameters (position).
-    open var onThumbTouchStart: ((Int) -> Void)?
+    open var onThumbTouchStart: ((Int) -> Void)? {
+        get { nil }
+        set {
+            onThumbTouchStartCancellable?.cancel()
+            if let newValue {
+                onThumbTouchStartCancellable = onThumbTouchStartPublisher
+                    .sink { c in
+                        newValue(c)
+                    }
+            }
+        }
+    }
+
+    /// A publisher for when the thumb touch start. Passes parameters (position).
+    open var onThumbTouchStartPublisher = PassthroughSubject<Int, Never>()
+    private var onThumbTouchStartCancellable: AnyCancellable?
 
     /// A callback when the thumb touch end. Passes parameters (position).
-    open var onThumbTouchEnd: ((Int) -> Void)?
+    open var onThumbTouchEnd: ((Int) -> Void)? {
+        get { nil }
+        set {
+            onThumbTouchEndCancellable?.cancel()
+            if let newValue {
+                onThumbTouchEndCancellable = onThumbTouchEndPublisher
+                    .sink { c in
+                        newValue(c)
+                    }
+            }
+        }
+    }
 
+    /// A publisher for when the thumb touch end. Passes parameters (position).
+    open var onThumbTouchEndPublisher = PassthroughSubject<Int, Never>()
+    private var onThumbTouchEndCancellable: AnyCancellable?
     
     //--------------------------------------------------
     // MARK: - Private Properties
@@ -250,13 +324,13 @@ open class CarouselScrollbar: View {
     func movePositionBackward() {
         position = position - 1
         scrollThumbToPosition(position)
-        self.onMoveBackward?(position)
+        onMoveBackwardPublisher.send(position)
     }
     
     func movePositionForward() {
         position = position + 1
         scrollThumbToPosition(position)
-        self.onMoveForward?(position)
+        onMoveForwardPublisher.send(position)
     }
     
     // Compute track width and should maintain minimum thumb width if needed
@@ -298,12 +372,13 @@ open class CarouselScrollbar: View {
     }
     
     private func scrollThumbToPosition(_ position: Int) {
-        self.setThumb(at: position)
+        setThumb(at: position)
-        self.onScrubberDrag?(position)
+        onScrubberDragPublisher.send(position)
     }
     
     private func setThumb(at position: Int) {
-        UIView.animate(withDuration: 0.1, delay: 0.0, options: .curveLinear, animations: {
+        UIView.animate(withDuration: 0.1, delay: 0.0, options: .curveLinear, animations: { [weak self] in
+            guard let self else { return }
             self.thumbView.frame.origin.x = CGFloat(Float((position) - 1) * self.computedWidth) + self.trackView.frame.origin.x
             self.updateActiveOverlays()
         })
@@ -318,7 +393,7 @@ open class CarouselScrollbar: View {
         let translation = sender.translation(in: thumbView)
         if sender.state == UIGestureRecognizer.State.began {
             trayOriginalCenter = thumbView.center
-            self.onThumbTouchStart?(position)
+            onThumbTouchStartPublisher.send(position)
         } else if sender.state == UIGestureRecognizer.State.changed {
             let draggedPositions = Int (ceil (Double(translation.x) / Double(computedWidth)))
             setThumb(at: position + draggedPositions)
@@ -327,7 +402,7 @@ open class CarouselScrollbar: View {
             let draggedPositions = Int (ceil (Double(translation.x) / Double(computedWidth)))
             position = ((position + draggedPositions) < 1) ? 1 : (position + draggedPositions)
             if sender.state == UIGestureRecognizer.State.ended {
-                self.onThumbTouchEnd?(position)
+                onThumbTouchEndPublisher.send(position)
             }
         }
     }