refactored checkbox coloring

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

VDS/Components/Checkbox/VDSCheckbox.swift

@@ -26,75 +26,58 @@ import Combine
     //--------------------------------------------------
     // MARK: - Private Properties
     //--------------------------------------------------
-    private func getCheckboxBackgroundColor(for disabled: Bool, surface: Surface) -> (on: UIColor, off: UIColor) {
+    private func getCheckboxBackgroundColor(viewModel: ModelType) -> UIColor {
-        if disabled {
+        var colors: (on: UIColor, off: UIColor)
-            if surface == .light {
+        if viewModel.disabled {
-                return (
+            if viewModel.surface == .light {
-                    on: VDSColor.interactiveDisabledOnlight,
+                colors = (on: VDSColor.interactiveDisabledOnlight, off: .clear)
-                    off: .clear)
             } else {
-                return (
+                colors = (on: VDSColor.interactiveDisabledOndark, off: .clear)
-                    on: VDSColor.interactiveDisabledOndark,
-                    off: .clear
-                )
             }
         } else {
-            if surface == .light {
+            if viewModel.surface == .light {
-                return (
+                colors = (on: VDSColor.elementsPrimaryOnlight, off: .clear)
-                    on: VDSColor.elementsPrimaryOnlight,
-                    off: .clear
-                )
             } else {
-                return (
+                colors = (on: VDSColor.elementsPrimaryOndark, off: .clear)
-                    on: VDSColor.elementsPrimaryOndark,
-                    off: .clear
-                )
             }
         }
+        return viewModel.on ? colors.on : colors.off
     }
     
-    private func getCheckboxBorderColor(for disabled: Bool, surface: Surface) -> (on: UIColor, off: UIColor) {
+    private func getCheckboxBorderColor(viewModel: ModelType) -> UIColor {
-        if disabled {
+        var colors: (on: UIColor, off: UIColor)
-            if surface == .light {
+        if viewModel.disabled {
-                return (
+            if viewModel.surface == .light {
-                    on: VDSColor.interactiveDisabledOnlight,
+                colors = (on: VDSColor.interactiveDisabledOnlight, off: VDSColor.interactiveDisabledOnlight)
-                    off: VDSColor.interactiveDisabledOnlight
-                )
             } else {
-                return (
+                colors = (on: VDSColor.interactiveDisabledOndark, off: VDSColor.interactiveDisabledOnlight)
-                    on: VDSColor.interactiveDisabledOndark,
-                    off: VDSColor.interactiveDisabledOnlight
-                )
             }
         } else {
-            if surface == .light {
+            if viewModel.surface == .light {
-                return (
+                colors = (on: VDSColor.elementsPrimaryOnlight, off: VDSFormControlsColor.borderOnlight)
-                    on: VDSColor.elementsPrimaryOnlight,
-                    off: VDSFormControlsColor.borderOnlight
-                )
             } else {
-                return (
+                colors = (on: VDSColor.elementsPrimaryOndark, off: VDSFormControlsColor.borderOndark)
-                    on: VDSColor.elementsPrimaryOndark,
-                    off: VDSFormControlsColor.borderOndark
-                )
             }
         }
+        return viewModel.on ? colors.on : colors.off
     }
     
-    private func getCheckboxCheckColor(for disabled: Bool, surface: Surface) -> UIColor {
+    private func getCheckboxCheckColor(viewModel: ModelType) -> UIColor {
+        var color: UIColor
         if disabled {
             if surface == .light {
-                return VDSColor.interactiveDisabledOndark
+                color = VDSColor.interactiveDisabledOndark
             } else {
-                return VDSColor.interactiveDisabledOnlight
+                color = VDSColor.interactiveDisabledOnlight
             }
         } else {
             if surface == .light {
-                return VDSColor.elementsPrimaryOndark
+                color = VDSColor.elementsPrimaryOndark
             } else {
-                return VDSColor.elementsPrimaryOnlight
+                color = VDSColor.elementsPrimaryOnlight
             }
         }
+        return viewModel.on ? color : .clear
     }
         
     private var mainStackView: UIStackView = {
@@ -138,8 +121,8 @@ import Combine
         return label
     }()
     
-    private var checkboxView: CheckBoxView = {
+    private var checkboxView: UIView = {
-        let view = CheckBoxView()
+        let view = UIView()
         view.translatesAutoresizingMaskIntoConstraints = false
         return view
     }()
@@ -235,7 +218,7 @@ import Combine
         
         checkboxHeightConstraint?.constant = checkboxSize.height
         checkboxWidthConstraint?.constant = checkboxSize.width
-        setCheckboxColor(viewModel: model)
+        updateCheckbox(viewModel: model)
     }
     
     public override func setupView() {
@@ -259,7 +242,7 @@ import Combine
         checkboxWidthConstraint = checkboxView.widthAnchor.constraint(equalToConstant: checkboxSize.width)
         checkboxWidthConstraint?.isActive = true
 
-        setCheckboxColor(viewModel: model)
+        updateCheckbox(viewModel: model)
         
         mainStackView.topAnchor.constraint(equalTo: topAnchor).isActive = true
         mainStackView.leadingAnchor.constraint(equalTo: leadingAnchor).isActive = true
@@ -268,19 +251,6 @@ import Combine
 
     }
     
-    /// Creates the check mark layer.
-    private func setCheckboxColor(viewModel: ModelType) {
-        
-        let background = getCheckboxBackgroundColor(for: viewModel.disabled, surface: viewModel.surface)
-        let border = getCheckboxBorderColor(for: viewModel.disabled, surface: viewModel.surface)
-        let checkColor = getCheckboxCheckColor(for: viewModel.disabled, surface: viewModel.surface)
-        let backgroundColor = viewModel.on ? background.on : background.off
-        checkboxView.backgroundColor = backgroundColor
-        checkboxView.borderColor = viewModel.on ? border.on : border.off
-        checkboxView.checkColor = viewModel.on ? checkColor : backgroundColor
-        checkboxView.isSelected = viewModel.on
-    }
-
     func ensureLabel(viewModel: ModelType) {
 
         //deal with labels
@@ -325,11 +295,69 @@ import Combine
     
     public override func reset() {
         super.reset()
-        setCheckboxColor(viewModel: model)
+        updateCheckbox(viewModel: model)
         setAccessibilityLabel()
         onChange = nil
     }
     
+    //--------------------------------------------------
+    // MARK: - Checkbox View
+    //--------------------------------------------------
+    /// Manages the appearance of the checkbox.
+    private var shapeLayer: CAShapeLayer?
+
+    private func updateCheckbox(viewModel: ModelType) {
+        //get the colors
+        let backgroundColor = getCheckboxBackgroundColor(viewModel: viewModel)
+        let borderColor = getCheckboxBorderColor(viewModel: viewModel)
+        let checkColor = getCheckboxCheckColor(viewModel: viewModel)
+
+        if let shapeLayer = shapeLayer, let sublayers = layer.sublayers, sublayers.contains(shapeLayer) {
+            shapeLayer.removeFromSuperlayer()
+            self.shapeLayer = nil
+        }
+
+        checkboxView.backgroundColor = backgroundColor
+        checkboxView.layer.borderColor = borderColor.cgColor
+        checkboxView.layer.cornerRadius = 2.0
+        checkboxView.layer.borderWidth = 1.0
+
+        if shapeLayer == nil {
+            let bounds = checkboxView.bounds
+            let length = max(bounds.size.height, bounds.size.width)
+            guard length > 0.0, shapeLayer == nil else { return }
+            
+            //draw the checkmark layer
+            let xInsetLeft = length * 0.25
+            let yInsetTop = length * 0.3
+            let innerWidth = length - (xInsetLeft + length * 0.25) // + Right X Inset
+            let innerHeight = length - (yInsetTop + length * 0.35) // + Bottom Y Inset
+            
+            let startPoint = CGPoint(x: xInsetLeft, y: yInsetTop + (innerHeight / 2))
+            let pivotOffSet = CGPoint(x: xInsetLeft + (innerWidth * 0.33), y: yInsetTop + innerHeight)
+            let endOffset = CGPoint(x: xInsetLeft + innerWidth, y: yInsetTop)
+            
+            let bezierPath = UIBezierPath()
+            bezierPath.move(to: startPoint)
+            bezierPath.addLine(to: pivotOffSet)
+            bezierPath.addLine(to: endOffset)
+
+            let shapeLayer = CAShapeLayer()
+            self.shapeLayer = shapeLayer
+            shapeLayer.frame = bounds
+            layer.addSublayer(shapeLayer)
+            shapeLayer.strokeColor = checkColor.cgColor
+            shapeLayer.fillColor = UIColor.clear.cgColor
+            shapeLayer.path = bezierPath.cgPath
+            shapeLayer.lineJoin = .miter
+            shapeLayer.lineWidth = 2
+            CATransaction.withDisabledAnimations {
+                shapeLayer.strokeEnd = model.on ? 1 : 0
+            }
+        }
+
+    }
+        
     //--------------------------------------------------
     // MARK: - Actions
     //--------------------------------------------------
@@ -375,7 +403,7 @@ import Combine
         let enabled = !viewModel.disabled
 
         ensureLabel(viewModel: viewModel)
-        setCheckboxColor(viewModel: viewModel)
+        updateCheckbox(viewModel: viewModel)
         setAccessibilityHint(enabled)
         setAccessibilityValue(viewModel.on)
         setAccessibilityLabel(viewModel.on)
@@ -384,75 +412,4 @@ import Combine
         layoutIfNeeded()
     }
     
-    private class CheckBoxView: UIView {
-        public var borderColor: UIColor = .black
-        public var checkColor: UIColor = .white
-        public var isSelected: Bool = false {
-            didSet {
-                if let shapeLayer = shapeLayer, let sublayers = layer.sublayers, sublayers.contains(shapeLayer) {
-                    shapeLayer.removeFromSuperlayer()
-                    self.shapeLayer = nil
-                }
-            }
-        }
-        
-        /// Manages the appearance of the checkbox.
-        private var shapeLayer: CAShapeLayer?
-
-        /// Creates the check mark layer.
-        private func drawShapeLayer() {
-            layer.borderColor = borderColor.cgColor
-            layer.cornerRadius = 2.0
-            layer.borderWidth = 1.0
-            shapeLayer?.strokeColor = checkColor.cgColor
-
-            guard let path = try? checkMarkPath(), shapeLayer == nil else { return }
-            
-            if shapeLayer == nil {
-                let shapeLayer = CAShapeLayer()
-                self.shapeLayer = shapeLayer
-                shapeLayer.frame = bounds
-                layer.addSublayer(shapeLayer)
-                shapeLayer.strokeColor = checkColor.cgColor
-                shapeLayer.fillColor = UIColor.clear.cgColor
-                shapeLayer.path = path
-                shapeLayer.lineJoin = .miter
-                shapeLayer.lineWidth = 2
-                CATransaction.withDisabledAnimations {
-                    shapeLayer.strokeEnd = isSelected ? 1 : 0
-                }
-            }
-        }
-        
-        override func layoutSubviews() {
-            super.layoutSubviews()
-            drawShapeLayer()
-        }
-        
-        /// - returns: The CGPath of a UIBezierPath detailing the path of a checkmark
-        private func checkMarkPath() throws -> CGPath {
-            let length = max(bounds.size.height, bounds.size.width)
-            guard length > 0.0 else { throw Error.boundsNotSet }
-            let xInsetLeft = length * 0.25
-            let yInsetTop = length * 0.3
-            let innerWidth = length - (xInsetLeft + length * 0.25) // + Right X Inset
-            let innerHeight = length - (yInsetTop + length * 0.35) // + Bottom Y Inset
-            
-            let startPoint = CGPoint(x: xInsetLeft, y: yInsetTop + (innerHeight / 2))
-            let pivotOffSet = CGPoint(x: xInsetLeft + (innerWidth * 0.33), y: yInsetTop + innerHeight)
-            let endOffset = CGPoint(x: xInsetLeft + innerWidth, y: yInsetTop)
-            
-            let bezierPath = UIBezierPath()
-            bezierPath.move(to: startPoint)
-            bezierPath.addLine(to: pivotOffSet)
-            bezierPath.addLine(to: endOffset)
-            
-            return bezierPath.cgPath
-        }
-        
-        enum Error: Swift.Error {
-            case boundsNotSet
-        }
-    }
 }
-