Fixing gesture collisions

Sources/SwiftUIPager/Helpers/SizeViewModifier.swift

@@ -8,17 +8,6 @@
 
 import SwiftUI
 
-/// Tracks the size of the view
-struct SizePreferenceKey: PreferenceKey {
-    static var defaultValue: CGSize = .zero
-
-    static func reduce(value: inout CGSize, nextValue: () -> CGSize) {
-        let newValue = nextValue()
-        guard value != newValue else { return }
-        value = newValue
-    }
-}
-
 /// This modifier wraps a view into a `GeometryReader` and tracks the available space by using `SizePreferenceKey` on the content
 struct SizeViewModifier: ViewModifier {
 
@@ -27,8 +16,6 @@ struct SizeViewModifier: ViewModifier {
     func body(content: Content) -> some View {
         GeometryReader { proxy in
             content
-                .preference(key: SizePreferenceKey.self,
-                            value: proxy.size)
                 .frame(width: proxy.size.width, height: proxy.size.height)
                 .onAppear (perform: {
                     self.size = proxy.size

Sources/SwiftUIPager/Pager+Buildable.swift

@@ -10,6 +10,11 @@ import SwiftUI
 
 extension Pager: Buildable {
 
+    /// Adds a `TapGesture` to the items to bring them to focus
+    public func itemTappable(_ value: Bool) -> Self {
+        mutating(keyPath: \.isItemTappable, value: value)
+    }
+
     /// Returns a horizontal pager
     public func horizontal() -> Self {
         mutating(keyPath: \.isHorizontal, value: true)

Sources/SwiftUIPager/Pager+Helper.swift

@@ -93,7 +93,7 @@ extension Pager {
     }
 
     /// Data that is being displayed at the moment
-    var dataDisplayed: [Data] {
+    var dataDisplayed: [Element] {
         Array(data[lowerPageDisplayed..<upperPageDisplayed])
     }
 
@@ -117,7 +117,7 @@ extension Pager {
     }
 
     /// Angle for the 3D rotation effect
-    func angle(for item: Data) -> Angle {
+    func angle(for item: Element) -> Angle {
         guard shouldRotate else { return .zero }
         guard let index = data.firstIndex(of: item) else { return .zero }
 
@@ -133,7 +133,7 @@ extension Pager {
     }
 
     /// Axis for the rotations effect
-    func axis(for item: Data) -> (CGFloat, CGFloat, CGFloat) {
+    func axis(for item: Element) -> (CGFloat, CGFloat, CGFloat) {
         guard shouldRotate else { return (0, 0, 0) }
         guard let index = data.firstIndex(of: item) else { return (0, 0, 0) }
 
@@ -142,7 +142,7 @@ extension Pager {
     }
 
     /// Scale that applies to a particular item
-    func scale(for item: Data) -> CGFloat {
+    func scale(for item: Element) -> CGFloat {
         guard isDragging else { return isFocused(item) ? 1 : interactiveScale }
 
         let totalIncrement = abs(totalOffset / pageDistance)
@@ -164,7 +164,7 @@ extension Pager {
     }
 
     /// Returns true if the item is focused on the screen.
-    func isFocused(_ item: Data) -> Bool {
+    func isFocused(_ item: Element) -> Bool {
         data.firstIndex(of: item) == currentPage
     }
 

Sources/SwiftUIPager/Pager.swift

@@ -29,7 +29,7 @@ import SwiftUI
 /// - 30 px of vertical insets
 /// - 0.6 shrink ratio for items that aren't focused.
 ///
-public struct Pager<Data, Content>: View  where Content: View, Data: Identifiable & Equatable {
+public struct Pager<Element, PageView>: View  where PageView: View, Element: Identifiable & Equatable {
 
     /// `Direction` determines the direction of the swipe gesture
     enum Direction {
@@ -58,13 +58,17 @@ public struct Pager<Data, Content>: View  where Content: View, Data: Identifiabl
     /*** Dependencies ***/
 
     /// `ViewBuilder` block to create each page
-    let content: (Data) -> Content
+    let content: (Element) -> PageView
 
     /// Array of items that will populate each page
-    var data: [Data]
+    var data: [Element]
 
     /*** ViewModified properties ***/
 
+    /// `true` if items are tapable
+    var isItemTappable: Bool = false
+
+    /// `true` if the pager is horizontal
     var isHorizontal: Bool = true
 
     /// Shrink ratio that affects the items that aren't focused
@@ -111,12 +115,12 @@ public struct Pager<Data, Content>: View  where Content: View, Data: Identifiabl
     /// - Parameter page: Binding to the index of the focused page
     /// - Parameter data: Array of items to populate the content
     /// - Parameter content: Factory method to build new pages
-    public init(page: Binding<Int>, data: [Data], @ViewBuilder content: @escaping (Data) -> Content) {
+    public init(page: Binding<Int>, data: [Element], @ViewBuilder content: @escaping (Element) -> PageView) {
         self._page = page
         self.data = data
         self.content = content
     }
-    
+
     public var body: some View {
         HStack(spacing: self.interactiveItemSpacing) {
             ForEach(self.dataDisplayed) { item in
@@ -127,11 +131,8 @@ public struct Pager<Data, Content>: View  where Content: View, Data: Identifiabl
                                       axis: (0, 0, 1))
                     .rotation3DEffect(self.angle(for: item),
                                       axis: self.axis(for: item))
-                    .onTapGesture (perform: {
-                        withAnimation(.spring()) {
-                            self.scrollToItem(item)
-                        }
-                    })
+                    .gesture(self.tapGesture(for: item))
+                    .disabled(self.isFocused(item) || !self.isItemTappable)
             }
             .offset(x: self.xOffset, y : 0)
         }
@@ -147,11 +148,20 @@ public struct Pager<Data, Content>: View  where Content: View, Data: Identifiabl
 extension Pager {
 
     /// Helper function to scroll to a specific item.
-    func scrollToItem(_ item: Data) {
+    func scrollToItem(_ item: Element) {
         guard let index = data.firstIndex(of: item) else { return }
         self.page = index
     }
 
+    func tapGesture(for item: Element) -> some Gesture {
+        TapGesture(count: 1)
+            .onEnded({ _ in
+                withAnimation(.spring()) {
+                    self.scrollToItem(item)
+                }
+            })
+    }
+
     /// `DragGesture` customized to work with `Pager`
     var swipeGesture: some Gesture {
         DragGesture()