Add a native SwiftUI button

.github/workflows/tests.yml

@@ -15,19 +15,25 @@ jobs:
     runs-on: macOS-latest
     strategy:
       matrix:
-        flags: [
-          '',
-          '--use-libraries',
-          '--use-static-frameworks'
+        podspec: [GoogleSignIn.podspec, GoogleSignInSwift.podspec]
+        flag: [
+          "", 
+          "--use-libraries", 
+          "--use-static-frameworks"
         ]
+        include:
+          - podspec: GoogleSignInSwift.podspec
+            includePodspecFlag: "--include-podspecs='GoogleSignIn.podspec'"
     steps:
     - uses: actions/checkout@v2
     - name: Update Bundler
       run: bundle update --bundler
     - name: Install Ruby gems with Bundler
       run: bundle install
     - name: Lint podspec using local source
-      run: pod lib lint --verbose ${{ matrix.flags }}
+      run: |
+        pod lib lint ${{ matrix.podspec }} --verbose \
+           ${{ matrix.includePodspecFlag }}  ${{ matrix.flag }}
 
   spm-build-test:
     runs-on: macOS-latest
@@ -44,14 +50,14 @@ jobs:
     - name: Build unit test target
       run: |
         xcodebuild \
-          -scheme GoogleSignIn \
+          -scheme GoogleSignIn-Package \
           -sdk ${{ matrix.sdk }} \
           -destination ${{ matrix.destination }} \
           build-for-testing
     - name: Run unit test target
       run: |
         xcodebuild \
-          -scheme GoogleSignIn \
+          -scheme GoogleSignIn-Package \
           -sdk ${{ matrix.sdk }} \
           -destination ${{ matrix.destination }} \
           test-without-building

GoogleSignIn.podspec

@@ -41,7 +41,8 @@ The Google Sign-In SDK allows users to sign in with their Google account from th
   s.pod_target_xcconfig = {
     'GCC_PREPROCESSOR_DEFINITIONS' => 'GID_SDK_VERSION=' + s.version.to_s,
     'HEADER_SEARCH_PATHS' => '"${PODS_TARGET_SRCROOT}"',
-    'DEFINES_MODULE' => 'YES'
+    'DEFINES_MODULE' => 'YES',
+    'COMBINE_HIDPI_IMAGES' => 'NO'
   }
   s.test_spec 'unit' do |unit_tests|
     unit_tests.platforms = {

GoogleSignInSwift.podspec

@@ -0,0 +1,27 @@
+Pod::Spec.new do |s|
+  s.name = 'GoogleSignInSwift'
+  s.version = '6.2.0'
+  s.swift_version = '4.0'
+  s.summary = 'Adds Swift-focused support for Google Sign-In.'
+  s.description = 'Additional Swift support for the Google Sign-In SDK.'
+  s.homepage = 'https://developers.google.com/identity/sign-in/ios/'
+  s.license = { :type => 'Apache', :file => 'LICENSE' }
+  s.authors = 'Google LLC'
+  s.source = {
+    :git => 'https://github.com/google/GoogleSignIn-iOS.git',
+    :tag => s.version.to_s
+  }
+  ios_deployment_target = '13.0'
+  macos_deployment_target = '10.15' 
+  s.ios.deployment_target = ios_deployment_target
+  s.osx.deployment_target = macos_deployment_target
+  s.prefix_header_file = false
+  s.source_files = [
+    'GoogleSignInSwift/Sources/*.swift',
+  ]
+  s.frameworks = [
+    'CoreGraphics',
+    'SwiftUI',
+  ]
+  s.dependency 'GoogleSignIn', '~> 6.2'
+end

GoogleSignInSwift/Sources/GoogleSignInButton.swift

@@ -0,0 +1,161 @@
+/*
+ * Copyright 2022 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import SwiftUI
+import CoreGraphics
+
+// MARK: - Sign-In Button
+
+/// A Google Sign In button to be used in SwiftUI.
+@available(iOS 13.0, macOS 10.15, *)
+public struct GoogleSignInButton: View {
+  @ObservedObject var viewModel: GoogleSignInButtonViewModel
+  private let action: () -> Void
+  private let fontLoaded: Bool
+
+  /// Creates an instance of the Google Sign-In button for use in SwiftUI
+  /// - parameter viewModel: An instance of `GoogleSignInButtonViewModel`
+  /// containing information on the button's scheme, style, and state.
+  /// - parameter action: A closure to use as the button's action upon press.
+  public init(
+    viewModel: GoogleSignInButtonViewModel,
+    action: @escaping () -> Void
+  ) {
+    self.viewModel = viewModel
+    self.action = action
+    self.fontLoaded = Font.loadCGFont()
+  }
+
+  public var body: some View {
+    Button(action: action) {
+      switch viewModel.style {
+      case .icon:
+        ZStack {
+          RoundedRectangle(cornerRadius: googleCornerRadius)
+            .fill(viewModel.buttonStyle.colors.iconColor)
+            .border(viewModel.buttonStyle.colors.iconBorderColor)
+          Image.signInButtonImage
+        }
+      case .standard, .wide:
+        HStack(alignment: .center) {
+          ZStack {
+            RoundedRectangle(cornerRadius: googleCornerRadius)
+              .fill(
+                viewModel.state == .disabled ?
+                  .clear : viewModel.buttonStyle.colors.iconColor
+              )
+              .frame(
+                width: iconWidth - iconPadding,
+                height: iconWidth - iconPadding
+              )
+            Image.signInButtonImage
+          }
+            .padding(.leading, 1)
+          Text(viewModel.style.buttonText)
+            .padding(.trailing, textPadding)
+          Spacer()
+        }
+      }
+    }
+    .font(signInButtonFont)
+    .buttonStyle(viewModel.buttonStyle)
+    .disabled(viewModel.state == .disabled)
+    .simultaneousGesture(
+      DragGesture(minimumDistance: 0)
+        .onChanged { _ in
+          guard viewModel.state != .disabled,
+                  viewModel.state != .pressed else { return }
+          viewModel.state = .pressed
+        }
+        .onEnded { _ in
+          guard viewModel.state != .disabled else { return }
+          viewModel.state = .normal
+        }
+    )
+  }
+}
+
+// MARK: - Google Icon Image
+
+@available(iOS 13.0, macOS 10.15, *)
+private extension Image {
+  static var signInButtonImage: Image {
+    guard let iconURL = Bundle.urlForGoogleResource(
+      name: googleImageName,
+      withExtension: "png"
+    ) else {
+      fatalError("Unable to load Google icon image url: \(Image.Error.unableToLoadGoogleIcon(name: googleImageName))")
+    }
+#if os(iOS) || targetEnvironment(macCatalyst)
+    guard let uiImage = UIImage(contentsOfFile: iconURL.path) else {
+      fatalError("Unable to load Google icon image url: \(Image.Error.unableToLoadGoogleIcon(name: googleImageName))")
+    }
+    return Image(uiImage: uiImage)
+#elseif os(macOS)
+    guard let nsImage = NSImage(contentsOfFile: iconURL.path) else {
+      fatalError("Unable to load Google icon image url: \(Image.Error.unableToLoadGoogleIcon(name: googleImageName))")
+    }
+    return Image(nsImage: nsImage)
+#else
+      fatalError("Unrecognized platform for SwiftUI sign in button image")
+#endif
+  }
+
+  enum Error: Swift.Error {
+    case unableToLoadGoogleIcon(name: String)
+  }
+}
+
+
+// MARK: - Google Font
+
+@available(iOS 13.0, macOS 10.15, *)
+private extension GoogleSignInButton {
+  var signInButtonFont: Font {
+    guard fontLoaded else {
+      return .system(size: fontSize, weight: .bold)
+    }
+    return .custom(fontNameRobotoBold, size: fontSize)
+  }
+}
+
+@available(iOS 13.0, macOS 10.15, *)
+private extension Font {
+  /// Load the font for the button.
+  /// - returns A `Bool` indicating whether or not the font was loaded.
+  static func loadCGFont() -> Bool {
+    // Check to see if the font has already been loaded
+#if os(iOS) || targetEnvironment(macCatalyst)
+    if let _ = UIFont(name: fontNameRobotoBold, size: fontSize) {
+      return true
+    }
+#elseif os(macOS)
+    if let _ = NSFont(name: fontNameRobotoBold, size: fontSize) {
+      return true
+    }
+#else
+    fatalError("Unrecognized platform for SwiftUI sign in button font")
+#endif
+    guard let fontURL = Bundle.urlForGoogleResource(
+      name: fontNameRobotoBold,
+      withExtension: "ttf"
+    ), let dataProvider = CGDataProvider(filename: fontURL.path),
+          let newFont = CGFont(dataProvider) else {
+            return false
+          }
+    return CTFontManagerRegisterGraphicsFont(newFont, nil)
+  }
+}

GoogleSignInSwift/Sources/GoogleSignInButtonBundleExtensions.swift

@@ -0,0 +1,64 @@
+/*
+ * Copyright 2022 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import Foundation
+
+// MARK: - Bundle Extensions
+
+#if SWIFT_PACKAGE
+let GoogleSignInBundleName = "GoogleSignIn_GoogleSignIn"
+#else
+let GoogleSignInBundleName = "GoogleSignIn"
+#endif
+
+@available(iOS 13.0, macOS 10.15, *)
+extension Bundle {
+  /// Gets the bundle for the SDK framework.
+  /// - returns An optional instance of `Bundle`.
+  /// - note If the main `Bundle` cannot be found, or if the `Bundle` cannot be
+  /// found via a class, then this will return nil.
+  static func gidFrameworkBundle() -> Bundle? {
+    if let mainPath = Bundle.main.path(
+      forResource: GoogleSignInBundleName,
+      ofType: "bundle"
+    ) {
+      return Bundle(path: mainPath)
+    }
+
+    let classBundle = Bundle(for: GoogleSignInButtonViewModel.self)
+
+    if let classPath = classBundle.path(
+      forResource: GoogleSignInBundleName,
+      ofType: "bundle"
+    ) {
+      return Bundle(path: classPath)
+    } else {
+      return nil
+    }
+  }
+
+  /// Retrieves the Google icon URL from the bundle.
+  /// - parameter name: The `String` name for the resource to look up.
+  /// - parameter ext: The `String` extension for the resource to look up.
+  /// - returns An optional `URL` if the resource is found, nil otherwise.
+  static func urlForGoogleResource(
+    name: String,
+    withExtension ext: String
+  ) -> URL? {
+    let bundle = Bundle.gidFrameworkBundle()
+    return bundle?.url(forResource: name, withExtension: ext)
+  }
+}

GoogleSignInSwift/Sources/GoogleSignInButtonStrings.swift

@@ -0,0 +1,58 @@
+/*
+ * Copyright 2022 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import Foundation
+
+/// A type retrieving the localized strings for the sign-in button text.
+@available(iOS 13.0, macOS 10.15, *)
+struct GoogleSignInButtonString {
+  /// Button text used as both key in localized strings files and default value
+  /// for the standard button.
+  private let standardButtonText = "Sign in"
+  /// Button text used as both key in localized strings files and default value
+  /// for the wide button.
+  private let wideButtonText = "Sign in with Google"
+
+  /// The table name for localized strings (i.e. file name before .strings
+  /// suffix).
+  private let stringsTableName = "GoogleSignIn"
+
+  /// Returns the localized string for the key if available, or the supplied
+  /// default text if not.
+  /// - parameter key: A `String` key to look up.
+  /// - parameter text: The default `String` text.
+  /// - returns Either the found `String` or the provided default text.
+  private func localizedString(key: String, text: String) -> String {
+    guard let frameworkBundle = Bundle.gidFrameworkBundle() else { return text }
+    return frameworkBundle.localizedString(
+      forKey: key,
+      value: text,
+      table: stringsTableName
+    )
+  }
+
+  /// Localized text for the standard button.
+  @available(iOS 13.0, macOS 10.15, *)
+  var localizedStandardButtonText: String {
+    return localizedString(key: standardButtonText, text: "No translation")
+  }
+
+  /// Localized text for the wide button.
+  @available(iOS 13.0, macOS 10.15, *)
+  var localizedWideButtonText: String {
+    return localizedString(key: wideButtonText, text: "No translation")
+  }
+}