feat: add new bottom sheet with animatable opacity, corner radius, an…

…d offset

Sources/ExtensionKit/SwiftUI/BottomSheet/BottomSheet.swift

@@ -0,0 +1,154 @@
+import SwiftUI
+
+/// Bottom sheet modal height
+public enum Height: Equatable {
+
+    /// Third of Screen size
+    case low
+    /// Half of Screen size
+    case mid
+    /// Full Screen size
+    case full
+    /// Custom screen size
+    case custom(CGFloat)
+
+    var value: CGFloat {
+        switch self {
+        case .low: return Screen.height * 0.33
+        case .mid: return Screen.height * 0.55
+        case .full: return Screen.height * 0.95
+        case let .custom(custom): return custom
+        }
+    }
+}
+
+/// Buttom sheet view with animatable offset, background opacity, modal corner radius
+struct BottomSheet<Content: View>: View {
+
+    private var cornerRadiusUpperbound: CGFloat = 10
+    private let backgroundOpacityUpperbound: CGFloat = 0.5
+    private let dragIndicatorVerticalPadding: CGFloat = 15
+
+    private var modalHeight = Height.mid
+    private let animation: Animation
+    private let indicatorHidden: Bool
+
+    @State private var modalCornerRadius: CGFloat = 10
+    @State private var backgroundOpacity: Double = 0.5
+    @State private var offset = CGSize.zero
+
+    @Binding var isPresented: Bool
+
+    let content: () -> Content
+
+    init(
+        isPresented: Binding<Bool>,
+        height: Height = .mid,
+        animation: Animation = .easeInOut(duration: 0.3),
+        thumbHidden: Bool = false,
+        @ViewBuilder content: @escaping () -> Content
+    ) {
+        self._isPresented = isPresented
+        self.modalHeight = height
+        self.animation = animation
+        self.content = content
+        self.indicatorHidden = thumbHidden
+    }
+
+    // MARK: - Computed vars
+
+    private var yRange: ClosedRange<CGFloat> {
+        return 0...modalHeight.value
+    }
+
+    var newOpacity: Double {
+        let y = offset.height
+        let lower = yRange.lowerBound
+        let upper = yRange.upperBound
+        let newOpacity = (y - lower) / ((upper - lower) / backgroundOpacityUpperbound)
+        return Double(backgroundOpacityUpperbound - newOpacity)
+    }
+
+    var newCornerRadius: CGFloat {
+        let y = offset.height
+        let lower = yRange.lowerBound
+        let upper = yRange.upperBound
+        let newCorner = (y - lower) / ((upper - lower) / cornerRadiusUpperbound)
+        return cornerRadiusUpperbound - newCorner
+    }
+
+    // MARK - Views
+
+    var body: some View {
+        ZStack(alignment: .bottom) {
+            if isPresented {
+                background
+                modal
+            }
+        }
+        .edgesIgnoringSafeArea(.all)
+    }
+
+    private var background: some View {
+        Color.black
+            .fillParent()
+            .opacity(backgroundOpacity)
+            .animation(animation)
+            .onTapGesture { isPresented.toggle() }
+    }
+
+    private var modal: some View {
+        VStack {
+            indicator
+            self.content()
+        }
+        .frame(
+            width: Screen.width,
+            height: modalHeight.value,
+            alignment: .top)
+            .background(Color.white)
+            .cornerRadius(modalCornerRadius)
+            .offset(y: offset.height)
+            .gesture(
+            DragGesture()
+                .onChanged(onChangedDragValueGesture)
+                .onEnded(onEndedDragValueGesture)
+            )
+            .animation(animation)
+            .transition(.move(edge: .bottom))
+    }
+
+    private var indicator: some View {
+        Rectangle()
+            .fill(Color(.systemGray4))
+            .frame(width: 50, height: 6)
+            .cornerRadius(3)
+            .padding(.vertical, dragIndicatorVerticalPadding)
+            .hide(if: indicatorHidden)
+    }
+
+    // MARK: - Helpers
+
+    private func onChangedDragValueGesture(_ value: DragGesture.Value) {
+        guard value.translation.height > 0 else { return }
+        self.offset = value.translation
+        backgroundOpacity = newOpacity
+        modalCornerRadius = newCornerRadius
+    }
+
+    private func onEndedDragValueGesture(_ value: DragGesture.Value) {
+        guard value.translation.height >= self.modalHeight.value / 2 else {
+            self.offset = .zero
+            self.backgroundOpacity = Double(backgroundOpacityUpperbound)
+            self.modalCornerRadius = cornerRadiusUpperbound
+            return
+        }
+
+        withAnimation(animation) {
+            self.isPresented.toggle()
+            self.offset = .zero
+            self.backgroundOpacity = Double(backgroundOpacityUpperbound)
+            self.modalCornerRadius = cornerRadiusUpperbound
+        }
+    }
+}

Sources/ExtensionKit/SwiftUI/Keyboard/KeyboardInfo.swift

@@ -1,7 +1,7 @@
 import UIKit
 
 /// Struct modeling keyboard updates
-public struct KeyboardInfo {
+public struct KeyboardInfo: Equatable {
     /// Keyboard height
     public var height: CGFloat = 0
     /// Keyboard animation curve

Sources/ExtensionKit/SwiftUI/View.swift

@@ -478,4 +478,30 @@ public extension View {
         }
     }
 
+    /// Adds a bottom sheet to View
+    /// - Parameters:
+    ///   - isPresented: Binding for presenting the View
+    ///   - height: Height, default .mid
+    ///   - animation: Animation
+    ///   - content: modal content
+    /// - Returns: View
+    func bottomSheet<Content: View>(
+        isPresented: Binding<Bool>,
+        height: Height = .mid,
+        animation: Animation = .easeInOut(duration: 0.3),
+        thumbHidden: Bool = false,
+        @ViewBuilder content: @escaping () -> Content
+    ) -> some View {
+        return ZStack {
+            self
+            BottomSheet(
+                isPresented: isPresented,
+                height: height,
+                animation: animation,
+                thumbHidden: thumbHidden,
+                content: content
+            )
+        }
+    }
+
 }