make sliders generic for binary floating point

Author: timdubbins

Sources/RangeSlider.swift

@@ -39,14 +39,14 @@ import SwiftUI
 ///
 ///  You can also use a step parameter to provide incremental steps along the path of the slider. For example,
 ///  if you have a slider with a range of 0 to 100, and you set the step value to 5, the slider’s increments would be 0, 5, 10, and so on.
-public struct RangeSlider: View {
+public struct RangeSlider<V: BinaryFloatingPoint>: View {
     // MARK: - Properties
-    
+
     /// The value of thumb on the left-hand-side.
-    @Binding var lowValue: Double
+    @Binding var lowValue: V
 
     /// The value of thumb on the right-hand-side.
-    @Binding var highValue: Double
+    @Binding var highValue: V
 
     /// The zIndex for the thumb on the right-hand-side.
     @State private var zIndexRHS: Double = 0
@@ -67,16 +67,16 @@ public struct RangeSlider: View {
     let displayBounds: ClosedRange<Double>?
 
     /// The lower-bound for the slider.
-    let minimumValue: Double
+    let minimumValue: V
 
     /// The upper-bound for the slider.
-    let maximumValue: Double
+    let maximumValue: V
 
     /// The distance between the upper and lower bounds.
-    let totalDistance: Double
+    let totalDistance: V
 
     /// The distance between each value. Defaults to zero.
-    let step: Double?
+    let step: V?
 
     /// Whether or not to display the low and high slider values.
     let showValues: Bool
@@ -92,10 +92,10 @@ public struct RangeSlider: View {
 
     /// The width of the sliders track.
     let lineWidth: CGFloat
-    
+
     /// A callback for when editing begins and ends.
     let onEditingChanged: (Bool) -> Void
-    
+
     public var body: some View {
         VStack {
             if title != nil {
@@ -182,7 +182,6 @@ public struct RangeSlider: View {
     }
 
     // MARK: - Methods
-
     /// Creates a slider to select two values from a given range.
     ///
     /// The values of the created instance are equal to the position of the given values within bounds, mapped into 0...1.
@@ -195,11 +194,11 @@ public struct RangeSlider: View {
     /// - Parameter onEditingChanged: A callback for when editing begins and ends.
     public init(
         _ title: String? = nil,
-        lowValue: Binding<Double>,
-        highValue: Binding<Double>,
+        lowValue: Binding<V>,
+        highValue: Binding<V>,
         in bounds: ClosedRange<Double>,
         displayBounds: ClosedRange<Double>? = nil,
-        step: Double? = nil,
+        step: V? = nil,
         showValues: Bool = true,
         showDifferenceOnEditing: Bool = false,
         color: Color = .blue,
@@ -208,8 +207,8 @@ public struct RangeSlider: View {
         onEditingChanged: @escaping (Bool) -> Void) {
             _lowValue = lowValue
             _highValue = highValue
-            minimumValue = bounds.lowerBound
-            maximumValue = bounds.upperBound
+            minimumValue = V(bounds.lowerBound)
+            maximumValue = V(bounds.upperBound)
             totalDistance = maximumValue - minimumValue
             _displayTitle = State(initialValue: title ?? "")
             self.title = showDifferenceOnEditing && title == nil ? "" : title
@@ -224,18 +223,18 @@ public struct RangeSlider: View {
             self.onEditingChanged = onEditingChanged
         }
 
-    private func scale(_ value: Double, translate: Bool = false) -> CGFloat {
+    private func scale(_ value: V, translate: Bool = false) -> V {
         guard let display = displayBounds else { return value }
 
-        let normal = value / (bounds.upperBound - bounds.lowerBound)
+        let normal = value / (maximumValue - minimumValue)
 
-        return normal * (display.upperBound - display.lowerBound)
+        return normal * V((display.upperBound - display.lowerBound))
     }
 
-    private func translate(_ value: Double) -> CGFloat {
-        guard let display = displayBounds else { return value }
+    private func translate(_ value: V) -> Double {
+        guard let display = displayBounds else { return Double(value) }
 
-        return value + display.lowerBound - bounds.lowerBound
+        return Double(value) + display.lowerBound - bounds.lowerBound
     }
 
     private func dragGesture(side: Thumb.Side, geo: GeometryProxy) -> some Gesture {
@@ -254,7 +253,7 @@ public struct RangeSlider: View {
                 }
 
                 if showDifferenceOnEditing {
-                    displayTitle = String(format: "%0.2f", scale(highValue - lowValue))
+                    displayTitle = String(format: "%0.2f", Double(scale(highValue - lowValue)))
                 }
             }
             .onEnded { _ in
@@ -275,16 +274,16 @@ public struct RangeSlider: View {
             }
     }
 
-    private func getNewValue(for side: Thumb.Side, _ translationX: CGFloat, _ geo: GeometryProxy) -> Double? {
+    private func getNewValue(for side: Thumb.Side, _ translationX: CGFloat, _ geo: GeometryProxy) -> V? {
         if startX == nil {
             startX = xPosition(side: side, geo)
             onEditingChanged(true)
         }
 
         guard let startX = startX else { return nil }
 
-        var newValue: Double {
-            var value = Double((startX + translationX) / geo.size.width) * totalDistance
+        var newValue: V {
+            var value = V((startX + translationX) / geo.size.width) * totalDistance
 
             if let step = step {
                 value = value - value.remainder(dividingBy: step)
@@ -305,7 +304,6 @@ public struct RangeSlider: View {
 }
 
 // MARK: - Components
-
 private struct Thumb: View {
     enum Side {
         case lhs
@@ -348,3 +346,4 @@ private struct Track: View {
             .frame(height: lineWidth)
     }
 }
+

Sources/RoundSlider.swift

@@ -121,9 +121,9 @@ public struct RoundSlider<V: BinaryFloatingPoint>: View {
                 .padding(.bottom, lineWidth)
                 .transition(.opacity)
 
-                // We change the id parameter of the view when
-                // we change its title. This resets the views
-                // state, allowing us to animate this change.
+            // We change the id parameter of the view when
+            // we change its title. This resets the views
+            // state, allowing us to animate this change.
                 .id("RoundSlider" + displayTitle)
 
             ZStack {
@@ -215,3 +215,4 @@ public struct RoundSlider<V: BinaryFloatingPoint>: View {
         start = translation
     }
 }
+