Support RTL locales

fermoya · May 20, 2022 · 9153fc1 · 9153fc1
1 parent 6b8ebd7
commit 9153fc1
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Showing 8 changed files with 32 additions and 15 deletions.
diff --git a/Documentation/Usage.md b/Documentation/Usage.md
@@ -74,13 +74,13 @@ Pager(...)
 
 <img src="/resources/usage/vertical-pager.gif" alt="Vertical pager" height="640"/>
 
-Pass a direction to `horizontal` or `vertical` to change the scroll direction. For instance, you can have a horizontal `Pager` that scrolls right-to-left:
+Pass a direction to `horizontal` or `vertical` to change the scroll direction. For instance, you can have a horizontal `Pager` that scrolls end-to-start:
 
 ```swift
 Pager(...)
     .itemSpacing(10)
     .alignment(.start)
-    .horizontal(.rightToLeft)
+    .horizontal(.endToStart)
     .itemAspectRatio(0.6)
 ```
 

diff --git a/Example/SwiftUIPagerExample/Examples/BizarreExampleView.swift b/Example/SwiftUIPagerExample/Examples/BizarreExampleView.swift
@@ -30,14 +30,14 @@ struct BizarreExampleView: View {
 
                 Spacer()
 
-                Text("Right to left, interactive").bold()
+                Text("Start to End, interactive").bold()
                 Pager(page: self.page2,
                       data: self.data,
                       id: \.self) {
                         self.pageView($0)
                 }
                 .itemSpacing(10)
-                .horizontal(.rightToLeft)
+                .horizontal(.endToStart)
                 .interactive(scale: 0.8)
                 .itemAspectRatio(0.7)
                 .background(Color.gray.opacity(0.5))

diff --git a/Sources/SwiftUIPager/PageConfiguration/SwipeDirection.swift b/Sources/SwiftUIPager/PageConfiguration/SwipeDirection.swift
@@ -7,16 +7,25 @@
 //
 
 import Foundation
+import SwiftUI
 
 /// Swipe direction for a vertical `Pager`
 @available(iOS 13.0, macOS 10.15, tvOS 13.0, watchOS 6.0, *)
 public enum HorizontalSwipeDirection {
 
     /// Pages move from left to right
-    case leftToRight
+    @available(*, deprecated, message: "Use `startToEnd` instead")
+    static var leftToRight: Self { .startToEnd }
 
     /// Pages move from right to left
-    case rightToLeft
+    @available(*, deprecated, message: "Use `endToStart` instead")
+    static var rightToLeft: Self { .endToStart }
+
+    /// Pages move forwards (i.e. left to right in English, right to left in Arabic)
+    case startToEnd
+
+    /// Pages move backwards (i.e. right to left in English, left to right in Arabic)
+    case endToStart
 }
 
 /// Swipe direction for a horizontal `Pager`
@@ -29,3 +38,11 @@ public enum VerticalSwipeDirection {
     /// Pages move from bottom to top
     case bottomToTop
 }
+
+extension Locale {
+    var isRightToLeft: Bool {
+        guard let language = self.languageCode else { return false }
+        let direction = Locale.characterDirection(forLanguage: language)
+        return direction == .rightToLeft
+    }
+}
diff --git a/Sources/SwiftUIPager/Pager+Buildable.swift b/Sources/SwiftUIPager/Pager+Buildable.swift
@@ -211,8 +211,8 @@ extension Pager: Buildable {
 
     /// Returns a horizontal pager
     ///
-    /// - Parameter swipeDirection: direction of the swipe. Defaults to `.leftToRight`
-    public func horizontal(_ swipeDirection: HorizontalSwipeDirection = .leftToRight) -> Self {
+    /// - Parameter swipeDirection: direction of the swipe. Defaults to `.startToEnd`
+    public func horizontal(_ swipeDirection: HorizontalSwipeDirection = .startToEnd) -> Self {
         mutating(keyPath: \.isHorizontal, value: true)
             .mutating(keyPath: \.horizontalSwipeDirection, value: swipeDirection)
     }

diff --git a/Sources/SwiftUIPager/Pager.swift b/Sources/SwiftUIPager/Pager.swift
@@ -82,7 +82,7 @@ public struct Pager<Element, ID, PageView>: View  where PageView: View, Element:
     var contentLoadingPolicy: ContentLoadingPolicy = .default
 
     /// Swipe direction for horizontal `Pager`
-    var horizontalSwipeDirection: HorizontalSwipeDirection = .leftToRight
+    var horizontalSwipeDirection: HorizontalSwipeDirection = .startToEnd
 
     /// Swipe direction for vertical `Pager`
     var verticalSwipeDirection: VerticalSwipeDirection = .topToBottom

diff --git a/Sources/SwiftUIPager/PagerContent+Buildable.swift b/Sources/SwiftUIPager/PagerContent+Buildable.swift
@@ -199,9 +199,9 @@ extension Pager.PagerContent: Buildable {
 
     /// Returns a horizontal pager
     ///
-    /// - Parameter swipeDirection: direction of the swipe. Defaults to `.leftToRight`
-    func horizontal(_ swipeDirection: HorizontalSwipeDirection = .leftToRight) -> Self {
-        let scrollDirectionAngle: Angle = swipeDirection == .leftToRight ? .zero : Angle(degrees: 180)
+    /// - Parameter swipeDirection: direction of the swipe. Defaults to `.startToEnd`
+    func horizontal(_ swipeDirection: HorizontalSwipeDirection = .startToEnd) -> Self {
+        let scrollDirectionAngle: Angle = swipeDirection == .startToEnd ? .zero : Angle(degrees: 180)
         return mutating(keyPath: \.isHorizontal, value: true)
             .mutating(keyPath: \.scrollDirectionAngle, value: scrollDirectionAngle)
     }

diff --git a/Sources/SwiftUIPager/PagerContent.swift b/Sources/SwiftUIPager/PagerContent.swift
@@ -358,7 +358,7 @@ extension Pager.PagerContent {
                 self.pagerModel.draggingVelocity = Double(offsetIncrement) / timeIncrement
             }
 
-            var newOffset = self.draggingOffset + offsetIncrement
+            var newOffset = self.draggingOffset + offsetIncrement * (Locale.current.isRightToLeft ? -1 : 1)
             if !allowsMultiplePagination {
                 newOffset = self.direction == .forward ? max(newOffset, self.pageRatio * -self.pageDistance) : min(newOffset, self.pageRatio * self.pageDistance)
             }

diff --git a/Tests/SwiftUIPagerTests/Pager+Buildable_Tests.swift b/Tests/SwiftUIPagerTests/Pager+Buildable_Tests.swift
@@ -20,7 +20,7 @@ final class Pager_Buildable_Tests: XCTestCase {
         XCTAssertTrue(pager.isHorizontal)
         XCTAssertTrue(pager.allowsDragging)
         XCTAssertFalse(pager.isInifinitePager)
-        XCTAssertEqual(pager.horizontalSwipeDirection, HorizontalSwipeDirection.leftToRight)
+        XCTAssertEqual(pager.horizontalSwipeDirection, HorizontalSwipeDirection.startToEnd)
         XCTAssertEqual(pager.verticalSwipeDirection, VerticalSwipeDirection.topToBottom)
         XCTAssertEqual(pager.interactiveScale, 1)
         XCTAssertEqual(pager.alignment, .center)
@@ -316,7 +316,7 @@ final class Pager_Buildable_Tests: XCTestCase {
 
     func test_GivenPager_WhenHorizontalRightToLeft_ThenScrollAngle() {
         var pager = givenPager.vertical()
-        pager = pager.horizontal(.rightToLeft)
+        pager = pager.horizontal(.endToStart)
 
         let pagerContent = pager.content(for: CGSize(width: 100, height: 100))
         XCTAssertTrue(pagerContent.isHorizontal)