Add imagen generation example to VertexAI Sample

FirebaseVertexAI/CHANGELOG.md

@@ -1,5 +1,6 @@
 # Unreleased
-- [feature] The Firebase Vertex AI SDK no longer requires `@preconcurrency` when imported in Swift 6.
+- [feature] The Vertex AI SDK no longer requires `@preconcurrency` when imported in Swift 6.
+- [feature] The Vertex AI Sample App now includes an image generation example.
 
 # 11.9.0
 - [feature] **Public Preview**: Added support for generating images using the

FirebaseVertexAI/Sample/ImagenScreen/ImagenScreen.swift

@@ -0,0 +1,67 @@
+// Copyright 2025 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
+
+struct ImagenScreen: View {
+  @StateObject var viewModel = ImagenViewModel()
+
+  enum FocusedField: Hashable {
+    case message
+  }
+
+  @FocusState
+  var focusedField: FocusedField?
+
+  var body: some View {
+    VStack {
+      TextField("Enter a prompt to generate an image", text: $viewModel.userInput)
+        .focused($focusedField, equals: .message)
+        .textFieldStyle(.roundedBorder)
+        .onSubmit {
+          onGenerateTapped()
+        }
+        .padding()
+
+      Button("Generate") {
+        onGenerateTapped()
+      }
+      .padding()
+      ForEach(viewModel.images, id: \.self) {
+        Image(uiImage: $0)
+          .resizable()
+          .scaledToFill()
+          .frame(minWidth: 0, maxWidth: .infinity, minHeight: 0, maxHeight: .infinity)
+          .aspectRatio(nil, contentMode: .fit)
+          .clipped()
+      }
+    }
+    .navigationTitle("Imagen sample")
+    .onAppear {
+      focusedField = .message
+    }
+  }
+
+  private func onGenerateTapped() {
+    focusedField = nil
+
+    Task {
+      await viewModel.generateImage(prompt: viewModel.userInput)
+    }
+  }
+}
+
+#Preview {
+  ImagenScreen()
+}

FirebaseVertexAI/Sample/ImagenScreen/ImagenViewModel.swift

@@ -0,0 +1,85 @@
+// Copyright 2025 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 FirebaseVertexAI
+import Foundation
+import OSLog
+import SwiftUI
+
+@MainActor
+class ImagenViewModel: ObservableObject {
+  private var logger = Logger(subsystem: Bundle.main.bundleIdentifier!, category: "generative-ai")
+
+  @Published
+  var userInput: String = ""
+
+  @Published
+  var images = [UIImage]()
+
+  @Published
+  var errorMessage: String?
+
+  @Published
+  var inProgress = false
+
+  private let model: ImagenModel
+
+  // 1. Initialize the Vertex AI service
+  private let vertexAI = VertexAI.vertexAI()
+
+  init() {
+    // 2. Configure Imagen settings
+    let modelName = "imagen-3.0-generate-002"
+    let safetySettings = ImagenSafetySettings(
+      safetyFilterLevel: .blockLowAndAbove
+    )
+    var generationConfig = ImagenGenerationConfig()
+    generationConfig.numberOfImages = 4
+    generationConfig.aspectRatio = .landscape4x3
+    generationConfig.addWatermark = false
+    generationConfig.negativePrompt = "people"
+
+    // 3. Initialize the Imagen model
+    model = vertexAI.imagenModel(
+      modelName: modelName,
+      generationConfig: generationConfig,
+      safetySettings: safetySettings
+    )
+  }
+
+  func generateImage(prompt: String) async {
+    guard !inProgress else {
+      print("Already generating images...")
+      return
+    }
+    do {
+      defer {
+        inProgress = false
+      }
+      inProgress = true
+      // 4. Call generateImages with the text prompt
+      let response = try await model.generateImages(prompt: prompt)
+
+      // 5. Print the reason images were filtered out, if any.
+      if let filteredReason = response.filteredReason {
+        print("Image(s) Blocked: \(filteredReason)")
+      }
+
+      // 6. Convert the image data to UIImage for display in the UI
+      images = response.images.compactMap { UIImage(data: $0.data) }
+    } catch {
+      logger.error("Error generating images: \(error)")
+    }
+  }
+}

FirebaseVertexAI/Sample/VertexAISample.xcodeproj/project.pbxproj

@@ -31,6 +31,8 @@
 		886F95E02B17D5010036F07A /* ConversationViewModel.swift in Sources */ = {isa = PBXBuildFile; fileRef = 88E10F562B1112F600C08E95 /* ConversationViewModel.swift */; };
 		886F95E12B17D5010036F07A /* ConversationScreen.swift in Sources */ = {isa = PBXBuildFile; fileRef = 88E10F542B1112CA00C08E95 /* ConversationScreen.swift */; };
 		886F95E32B17D6630036F07A /* GenerativeAIUIComponents in Frameworks */ = {isa = PBXBuildFile; productRef = 886F95E22B17D6630036F07A /* GenerativeAIUIComponents */; };
+		DEFECAA92D7B4CCD00EF9621 /* ImagenViewModel.swift in Sources */ = {isa = PBXBuildFile; fileRef = DEFECAA72D7B4CCD00EF9621 /* ImagenViewModel.swift */; };
+		DEFECAAA2D7B4CCD00EF9621 /* ImagenScreen.swift in Sources */ = {isa = PBXBuildFile; fileRef = DEFECAA62D7B4CCD00EF9621 /* ImagenScreen.swift */; };
 /* End PBXBuildFile section */
 
 /* Begin PBXFileReference section */
@@ -60,6 +62,8 @@
 		88E10F582B11131900C08E95 /* ChatMessage.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ChatMessage.swift; sourceTree = "<group>"; };
 		88E10F5A2B11133E00C08E95 /* MessageView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = MessageView.swift; sourceTree = "<group>"; };
 		88E10F5C2B11135000C08E95 /* BouncingDots.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = BouncingDots.swift; sourceTree = "<group>"; };
+		DEFECAA62D7B4CCD00EF9621 /* ImagenScreen.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ImagenScreen.swift; sourceTree = "<group>"; };
+		DEFECAA72D7B4CCD00EF9621 /* ImagenViewModel.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ImagenViewModel.swift; sourceTree = "<group>"; };
 /* End PBXFileReference section */
 
 /* Begin PBXFrameworksBuildPhase section */
@@ -146,6 +150,7 @@
 		8848C8262B0D04BC007B434F = {
 			isa = PBXGroup;
 			children = (
+				DEFECAA82D7B4CCD00EF9621 /* ImagenScreen */,
 				88B8A9352B0FCBA700424728 /* GenerativeAIUIComponents */,
 				869200B22B879C4F00482873 /* GoogleService-Info.plist */,
 				8848C8312B0D04BC007B434F /* VertexAISample */,
@@ -279,6 +284,15 @@
 			path = Screens;
 			sourceTree = "<group>";
 		};
+		DEFECAA82D7B4CCD00EF9621 /* ImagenScreen */ = {
+			isa = PBXGroup;
+			children = (
+				DEFECAA62D7B4CCD00EF9621 /* ImagenScreen.swift */,
+				DEFECAA72D7B4CCD00EF9621 /* ImagenViewModel.swift */,
+			);
+			path = ImagenScreen;
+			sourceTree = "<group>";
+		};
 /* End PBXGroup section */
 
 /* Begin PBXNativeTarget section */
@@ -374,6 +388,8 @@
 				886F95E02B17D5010036F07A /* ConversationViewModel.swift in Sources */,
 				886F95DD2B17D5010036F07A /* MessageView.swift in Sources */,
 				886F95DC2B17BAEF0036F07A /* PhotoReasoningScreen.swift in Sources */,
+				DEFECAA92D7B4CCD00EF9621 /* ImagenViewModel.swift in Sources */,
+				DEFECAAA2D7B4CCD00EF9621 /* ImagenScreen.swift in Sources */,
 				886F95DB2B17BAEF0036F07A /* PhotoReasoningViewModel.swift in Sources */,
 				886F95E12B17D5010036F07A /* ConversationScreen.swift in Sources */,
 				88263BF02B239C09008AB09B /* ErrorView.swift in Sources */,

FirebaseVertexAI/Sample/VertexAISample/ContentView.swift

@@ -45,6 +45,11 @@ struct ContentView: View {
         } label: {
           Label("Function Calling", systemImage: "function")
         }
+        NavigationLink {
+          ImagenScreen()
+        } label: {
+          Label("Imagen", systemImage: "camera.circle")
+        }
       }
       .navigationTitle("Generative AI Samples")
     }