你可以使用 ML Kit 翻譯不同語言的文字。機器學習套件 可以在超過 90 個 50 種語言。
立即試用
- 使用範例應用程式試試 請查看此 API 的使用範例。
事前準備
- 在 Podfile 中加入下列 ML Kit Pod:
pod 'GoogleMLKit/Translate', '15.5.0'
- 安裝或更新專案的 Pod 後,請使用
.xcworkspace
。Xcode 12.4 以上版本支援 ML Kit。
翻譯一段文字
如何在兩種語言之間翻譯字串:
建立
Translator
物件,並使用來源和目標設定該物件 語言:Swift
// Create an English-German translator: let options = TranslatorOptions(sourceLanguage: .english, targetLanguage: .german) let englishGermanTranslator = Translator.translator(options: options)
Objective-C
// Create an English-German translator: MLKTranslatorOptions *options = [[MLKTranslatorOptions alloc] initWithSourceLanguage:MLKTranslateLanguageEnglish targetLanguage:MLKTranslateLanguageGerman]; MLKTranslator *englishGermanTranslator = [MLKTranslator translatorwithOptions:options];
如果您不知道輸入文字的語言,可以使用語言 識別 API 會提供語言標記然後將語言標記轉換為 ML Kit 列舉項目程式碼取決於您使用的語言:
- Swift:撥打
TranslateLanguage.fromLanguageTag()
取得TranslateLanguage
- Objective-C:撥打
MLKTranslateLanguageForLanguageTag()
取得MLKTranslateLanguage
請避免同時在裝置上保留過多語言模型,
- Swift:撥打
確認所需翻譯模型已下載到裝置。 確認模型可用前,請勿呼叫
translate(_:completion:)
。Swift
let conditions = ModelDownloadConditions( allowsCellularAccess: false, allowsBackgroundDownloading: true ) englishGermanTranslator.downloadModelIfNeeded(with: conditions) { error in guard error == nil else { return } // Model downloaded successfully. Okay to start translating. }
Objective-C
MLKModelDownloadConditions *conditions = [[MLKModelDownloadConditions alloc] initWithAllowsCellularAccess:NO allowsBackgroundDownloading:YES]; [englishGermanTranslator downloadModelIfNeededWithConditions:conditions completion:^(NSError *_Nullable error) { if (error != nil) { return; } // Model downloaded successfully. Okay to start translating. }];
語言模型大約有 30 MB 的空間,因此不需要下載 除非使用者另有指定,否則只能透過 Wi-Fi 下載下載。個人中心 不再需要模型 請參閱「明確管理翻譯模型」。
確認下載模型後,請在 將原文語言轉換為
translate(_:completion:)
:Swift
englishGermanTranslator.translate(text) { translatedText, error in guard error == nil, let translatedText = translatedText else { return } // Translation succeeded. }
Objective-C
[englishGermanTranslator translateText:text completion:^(NSString *_Nullable translatedText, NSError *_Nullable error) { if (error != nil || translatedText == nil) { return; } // Translation succeeded. }];
ML Kit 會將文字翻譯成您設定的目標語言 將翻譯的文字傳遞至完成處理常式。
譯者的生命週期是由 ARC (自動參照計算) 控管, 這是 iOS 開發作業的建議慣例開發人員可以遵守 移除所有高度的參考檔案後,譯者即可取消配置。
譯者在記憶體中載入時,可以佔用 30 MB 至 150 MB 的空間。開發人員 建立並行專案時,請務必考量裝置/應用程式的記憶體預算 避免在裝置上保留過多語言模型 一起使用
明確管理翻譯模型
按照上述方式使用翻譯 API 時,ML Kit 會自動使用 視需要下載特定語言專屬的翻譯模型至裝置。個人中心 也可以明確管理 整合了 ML Kit 的翻譯模型管理 API可用的值包括 舉例來說,如果您想事先下載模型,或是刪除不需要的模型 登入裝置。
如要取得儲存在裝置上的翻譯模型:
Swift
let localModels = ModelManager.modelManager().downloadedTranslateModels
Objective-C
NSSet*localModels = [MLKModelManager modelManager].downloadedTranslateModels;
如要刪除模型:
Swift
// Delete the German model if it's on the device. let germanModel = TranslateRemoteModel.translateRemoteModel(language: .german) ModelManager.modelManager().deleteDownloadedModel(germanModel) { error in guard error == nil else { return } // Model deleted. }
Objective-C
// Delete the German model if it's on the device. MLKTranslateRemoteModel *germanModel = [MLKTranslateRemoteModel translateRemoteModelWithLanguage:MLKTranslateLanguageGerman]; [[MLKModelManager modelManager] deleteDownloadedModel:germanModel completion:^(NSError * _Nullable error) { if (error != nil) { return; } // Model deleted.
如何下載模型:
Swift
// Download the French model. let frenchModel = TranslateRemoteModel.translateRemoteModel(language: .french) // Keep a reference to the download progress so you can check that the model // is available before you use it. progress = ModelManager.modelManager().download( frenchModel, conditions: ModelDownloadConditions( allowsCellularAccess: false, allowsBackgroundDownloading: true ) )
如要向「NotificationCenter
」取得下載狀態,請註冊
mlkitModelDownloadDidSucceed
和
mlkitModelDownloadDidFail
。請務必對「self
」使用較弱的參照
,因為下載可能需要一些時間,而且
物件即可釋出。例如:
NotificationCenter.default.addObserver( forName: .mlkitModelDownloadDidSucceed, object: nil, queue: nil ) { [weak self] notification in guard let strongSelf = self, let userInfo = notification.userInfo, let model = userInfo[ModelDownloadUserInfoKey.remoteModel.rawValue] as? TranslateRemoteModel, model == frenchModel else { return } // The model was downloaded and is available on the device } NotificationCenter.default.addObserver( forName: .mlkitModelDownloadDidFail, object: nil, queue: nil ) { [weak self] notification in guard let strongSelf = self, let userInfo = notification.userInfo, let model = userInfo[ModelDownloadUserInfoKey.remoteModel.rawValue] as? TranslateRemoteModel else { return } let error = userInfo[ModelDownloadUserInfoKey.error.rawValue] // ... }
Objective-C
// Download the French model. MLKModelDownloadConditions *conditions = [[MLKModelDownloadConditions alloc] initWithAllowsCellularAccess:NO allowsBackgroundDownloading:YES]; MLKTranslateRemoteModel *frenchModel = [MLKTranslateRemoteModel translateRemoteModelWithLanguage:MLKTranslateLanguageFrench]; // Keep a reference to the download progress so you can check that the model // is available before you use it. self.downloadProgress = [[MLKModelManager modelManager] downloadModel:frenchModel conditions:conditions];
如要向「NSNotificationCenter
」取得下載狀態,請註冊
MLKModelDownloadDidSucceedNotification
和
MLKModelDownloadDidFailNotification
。請務必使用弱式參照
觀察器區塊中的 self
,因為下載可能需要一些時間,
可在下載完成後釋放。
__block MyViewController *weakSelf = self; [NSNotificationCenter.defaultCenter addObserverForName:MLKModelDownloadDidSucceedNotification object:nil queue:nil usingBlock:^(NSNotification * _Nonnull note) { if (weakSelf == nil | note.userInfo == nil) { return; } MLKTranslateRemoteModel *model = note.userInfo[MLKModelDownloadUserInfoKeyRemoteModel]; if ([model isKindOfClass:[MLKTranslateRemoteModel class]] && model == frenchModel) { // The model was downloaded and is available on the device } }]; [NSNotificationCenter.defaultCenter addObserverForName:MLKModelDownloadDidFailNotification object:nil queue:nil usingBlock:^(NSNotification * _Nonnull note) { if (weakSelf == nil | note.userInfo == nil) { return; } NSError *error = note.userInfo[MLKModelDownloadUserInfoKeyError]; }];